What You Se is Not What You Get: The Influence of Aproach and Escape Motivation on Visual Perception and Behavior in Spider-fearful Individuals by Arash Farshid A disertation submited to the Graduate Faculty of Auburn University in partial fulfilment of the requirements for the Degree of Doctor of Philosophy Auburn, Alabama August 2, 2014 Keywords: specific phobia, perceptual bias, visual perception Copyright 2014 by Arash Farshid Approved by Jefrey S. Katz, Chair, Alumni Profesor of Psychology Barry R. Burkhart, Profesor of Psychology Alejandro A. Lazarte, Associate Profesor of Psychology Christopher J. Correia, Profesor of Psychology ii Abstract The present study examined the influence of approach and escape motivation on visual perception, and whether these perceptions afect action responses in a direction congruent with these respective motivations, by comparing thirsty and quenched individuals (Experiment 1) as wel as spider-fearful and spider-tolerant individuals (Experiment 2). In Experiment 1, thirsty individuals perceived a water bottle to be closer than quenched individuals. The closer the water bottle was perceived, the shorter the distance that participants stepped away from the water bottle relative to their baseline. In Experiment 2, spider-fearful individuals perceived a stimulus that evoked threat (tarantula) as physicaly closer and bigger than stimuli that evoked disgust or a neutral afective signal compared to spider-tolerant individuals. As participants endorsed higher degrees of spider-related fear (on the FSQ and SPQ) and perceived greater levels of threat, they perceived the contained tarantula as closer in egocentric distance and longer in size. The closer and bigger the tarantula was perceived by participants, the longer the distance that they stepped away from it relative to their baseline. This study is the first to demonstrate a linear asociation betwen biased visual perception and approach/escape behavior, in which the degree of the bias predicts the extent of the relevant action response. These results suggest that visual perception and action responses are not mutualy exclusive proceses but rather are interconnected psychological events, which can be partialy predicted relationaly. Potential implications of this key finding are discussed. iii Acknowledgements I am indebted to many people who have helped me complete this journey, which has culminated in the completion of this disertation. First and foremost, I would like to thank Dr. Jeffrey Katz. He has embodied many roles for me, including major profesor, mentor, unwavering supporter, felow sports enthusiast, and friend. I would not have been able to endure the trials and tribulations of graduate training without his peerles leadership and guidance. Second, I would like to thank the rest of my commite members?Drs. Alejandro Lazarte, Barry Burkhart, and Christopher Correia. Each has served on multiple commites of mine due to their expert guidance, generosity, and support. Third, I give thanks to my parents for their love and unconditional support for my education throughout my life. My work ethic and dedication to academic pursuits can only be atributed to them. Last but not least, I would like to thank my friends for their encouragement and moral support during this disertation proces. Those who deserve particular recognition include Thomas (?Alex?) Daniel, Adam Goodman, Christy Blevins, Megan Heinicke, Sara Hirsch, and May Kim. Their support meant more to me than they?ll ever know. iv Table of Contents Abstract ......................................................................................................................................... ii Acknowledgements ...................................................................................................................... iii List of Figures .............................................................................................................................. vi I. Introduction ............................................................................................................................. 1 Overview ......................................................................................................................... 1 Conformity Influences on Visual Perception .................................................................. 2 New Look and its Empirical Support .............................................................................. 3 Criticisms of the New Look Approach ........................................................................... 9 Current Directions in the New Look Literature ............................................................ 17 Background on Specific Phobia .................................................................................... 24 Present Study ................................................................................................................ 25 Overarching Purpose and Potential Implications .......................................................... 28 II. Experiment 1 ........................................................................................................................ 30 Method .......................................................................................................................... 30 Participants ..................................................................................................... 30 Materials ........................................................................................................ 30 Design and Procedure .................................................................................... 30 Results ........................................................................................................................... 31 Manipulation Checks ..................................................................................... 31 v Perceptual Judgment Acuracy ...................................................................... 32 Action Response ............................................................................................ 33 Discussion ..................................................................................................................... 33 III. Experiment 2 ....................................................................................................................... 36 Method .......................................................................................................................... 36 Participant Selection ...................................................................................... 36 Measures ........................................................................................................ 36 Design ............................................................................................................ 37 Procedure ....................................................................................................... 38 Results ........................................................................................................................... 39 Sample Characteristics ................................................................................... 39 Manipulation Checks ..................................................................................... 40 Perceptual Judgment Acuracy ...................................................................... 42 Action Response ............................................................................................ 44 Discussion ..................................................................................................................... 46 IV. General Discussion ............................................................................................................. 49 References ................................................................................................................................. 53 Appendix A ............................................................................................................................... 92 Appendix B ............................................................................................................................... 94 vi List of Figures Figure 1. ...................................................................................................................................... 61 Figure 2. ...................................................................................................................................... 62 Figure 3. ...................................................................................................................................... 63 Figure 4. ...................................................................................................................................... 64 Figure 5. ...................................................................................................................................... 65 Figure 6. ...................................................................................................................................... 66 Figure 7. ...................................................................................................................................... 67 Figure 8. ...................................................................................................................................... 68 Figure 9. ...................................................................................................................................... 69 Figure 10. .................................................................................................................................... 70 Figure 11. .................................................................................................................................... 71 Figure 12. .................................................................................................................................... 72 Figure 13. .................................................................................................................................... 73 Figure 14. .................................................................................................................................... 74 Figure 15. .................................................................................................................................... 75 Figure 16. .................................................................................................................................... 76 Figure 17. .................................................................................................................................... 77 Figure 18. .................................................................................................................................... 78 Figure 19. .................................................................................................................................... 79 vii Figure 20. .................................................................................................................................... 80 Figure 21. .................................................................................................................................... 81 Figure 22. .................................................................................................................................... 82 Figure 23. .................................................................................................................................... 83 Figure 24. .................................................................................................................................... 84 Figure 25. .................................................................................................................................... 85 Figure 26. .................................................................................................................................... 86 Figure 27. .................................................................................................................................... 87 Figure 28. .................................................................................................................................... 88 Figure 29. .................................................................................................................................... 89 Figure 30. .................................................................................................................................... 90 Figure 31. .................................................................................................................................... 91 1 I. Introduction For centuries, human perception was viewed as a pasive proces involving litle complexity (Bruner & Goodman, 1947). The prevailing view as that individuals perceiving incoming sensory stimuli merely acted as recording instruments, unafected by psychological factors. However, as research methodologies in psychology grew more and more sophisticated in the first half of the 20 th century, these views became increasingly chalenged. As Louis Thurstone (1944) argued, ?In these days when we insist so frequently on the interdependence of al aspects of personality, it would be dificult to maintain that any of these functions, such as perception, is isolated from the rest of the dynamical system that constitutes the person? (p. 47). These and other similar views consequently spurred a new movement in the literature to explore how the proces of perception is influenced by psychological factors (from both internal and external presures) and vice versa. Overview The structure of this Introduction wil follow a historical progresion of the literature exploring the influence of psychological factors on visual perception. When the literature was in its infancy, external influences on perception (viz., conformity effects) were primarily emphasized. As the literature evolved, however, internal influences on perception (e.g., motivation, desire, and needs of the organism) began to receive more atention. Acordingly, the Introduction wil begin by briefly reviewing two clasic empirical studies on the role of conformity in making perceptual judgments. What follows is a review of the literature on internal states and their influence on visual perception, criticisms of this literature that led to its 2 dormancy, and its recent resurgence. The Introduction wil conclude by discussing the present study along with a brief review of specific phobia. The purpose and hypothesized results of the present study wil also be discussed. Conformity Influences on Visual Perception A series of early studies investigated the role of conformity in making perceptual judgments. In one clasic experiment, Sherif (1936) examined the influence of group conformity on the autokinetic efect?the ilusory phenomenon in which individuals shown a stationary point of light in a uniformly dark room report to se it move, which is said to occur because there lacks a stable reference point to anchor the light?s position for the perceiver (Aronson, Wilson, & Akert, 2005). When participants were asesed individualy, their estimates of how far the point of light moved varied greatly across participants. After this initial asesment, these participants were placed in a group with two other individuals (each having undergone the same prior experience individualy) and were each asked to provide their estimate of how far the light had moved. Despite providing diferent initial estimates, the group would often generate a common estimate. To ensure that participants were not simply providing socialy desirable estimates in front of the group (i.e., reaching consensus despite believing that their original estimate was correct), the participants were brought back on a diferent day and asked to make the same judgment without any other participant in the room. Again, participants were significantly more likely to provide the group?s estimate over their own initial estimate. Acording to Sherif, the results indicated that the participants had been relying on each other as a source of information due to the ambiguity of the situation (referred to as informational social influence). In another clasic experiment, Asch (1951) investigated the power of conformity using a diferent perceptual judgment task. The purpose of Asch?s study was to examine whether 3 conformity ceased to influence people?s perceptual judgments when the situation was no longer ambiguous. In his experiment, Asch showed groups of nine two cards, one with a single reference line and the other with three comparison lines (labeled 1, 2, and 3). Students were asked to determine and announce out loud which of the three comparison lines on the second card most closely matched the length of the reference line on the first card. The lengths of the two incorrect comparison lines were generated in such a way to make the answer obvious, thereby making the situation unambiguous. Among the nine members in the group, eight were confederates of the experimenter. The seating arrangements of the students were set up in such a way to ensure that the actual subject in the experiment was caled upon next-to-last in the group. The confederates were instructed beforehand to deliberately provide the same incorrect response on many of the trials. Despite the unambiguous nature of the situation, 76% of the participants conformed on at least one trial. Unlike the Sherif (1936) study, participants reported that they did not actualy believe in their conforming answer but had simply conformed to avoid ridicule (referred to as normative social influence). Studies on conformity have ilustrated how social factors can afect perception. But what about internal states? Can internal factors, such as one?s needs and desires, also influence perception? A paradigm shift in how perception was thought to be influenced gave rise to a new wave of research steming from a particular theory in perception, known as the New Look approach. New Look and its Empirical Suport The New Look approach to perception was first developed by Bruner and Goodman (1947), who posited that the perception of stimuli is not just an isolated proces but rather is one that is also guided by internal events. More specificaly, they suggested that perception is a constructive 4 proces that is driven by top-down factors, such as the atitudes, needs, desires, and expectations of the individual. Bruner and Goodman further argued that the perceiver employs strategies for dealing with afective stimuli, which they termed the perceptual defense and vigilance hypothesis?the idea that the perception of stimuli may be enhanced (perceptual vigilance) or inhibited (perceptual defense) as function of the stimuli?s afective quality. In their seminal study, Bruner and Goodman proposed that there existed three relevant principles in perception: ?1. The greater the social value of an object, the more wil it be susceptible to organization by behavioral determinants. It will be selected perceptualy from among alternative perceptual objects, wil become fixated as a perceptual response tendency, and wil become perceptualy accentuated. 2. The greater the individual ned for a socially valued object, the more marked wil be the operation of behavioral determinants. 3. Perceptual equivocality wil facilitate the operation of behavioral determinants only in so far as equivocality reduces the operation of autochthonous determinants without reducing the efectivenes of behavioral determinants? (p. 36-37). Bruner and Goodman were particularly interested in examining what they termed, accentuation?the tendency for desirable objects to be sen with greater clarity. As a result, a series of experiments were performed investigating this isue. Thirty 10-year-old children of average inteligence were randomly asigned to one of three conditions: two experimental and one control. Participants were provided with an apparatus that had a knob on one end that could be turned to adjust the diameter of a circle of light that was projected onto a screen. Participants sat in a chair in front of the screen and were instructed to make the circle of light the same size as various objects. The task demands for the children in the two experimental groups were identical. Initialy, each child was asked to estimate from memory the sizes of various coins, ranging from a penny to a half dollar, in both ascending and descending order. Participants were not given any corrective fedback after making their judgments. Then, they were asked to make the same judgments with the coins present. For each judgment, the corresponding coin was placed in the center of the participant?s left palm for reference. Participants were granted unlimited time to 5 make their judgments. Children asigned to the control condition folowed an identical procedure except for one major diference: instead of coins, identicaly-sized cardboard discs were used. Two main findings were found. First, size estimates for coins were significantly larger than were size estimates for cardboard discs. Second, the deviation betwen apparent size and actual size of the coins grew larger as the value of the coin increased. The results suggested that socialy- valued objects are judged larger in size than objects without social value. To ases the second proposed principle, a follow-up experiment was conducted (Bruner & Goodman, 1947). In Experiment 2, the experimental group was divided into two subgroups: a poor group and a rich group, with each comprising ten children; there was no control group. Children in the poor and rich groups were asked to estimate coin sizes both from memory and with the coins present, with the same value range and order of presentation as in Experiment 1. Consistent with their hypothesis, the authors found that children in the poor group significantly overestimated the coin sizes compared to children in the rich group, suggesting that poor children display a greater need for money (a socialy valued object) than rich children. When the results for size estimations of coins were broken down by coin presence (coin present vs. coin absent) betwen poor and rich children, the following patern emerged: the percent deviation betwen the apparent size and the actual size of the coins was greater among poor children when the coins were present compared to when they were absent, whereas the opposite was true among rich children. In another study, a series of experiments were performed investigating the efects of need states (thirst and hunger) on matching the luminance of corresponding need-related objects, which were projected pictures of various food and liquid items (Gilchrist & Nesberg, 1952). For each experiment, participants were seated in a darkened room in front of a 12-foot projection 6 screen. They were provided with an apparatus with an atached knob for adjusting the luminance of the pictures. Once introduced to the apparatus, participants were told that they would be viewing a series of pictures, the order of which was randomized. Each picture was presented on the projection screen for 15 seconds before disappearing from view. After several intervening seconds, the picture reappeared but with a diferent level of luminance. Participants were instructed to adjust the luminance of the second picture to match that of the original by turning the knob. In Experiment 1, 26 participants were recruited from an introductory psychology course, al of whom were instructed beforehand to abstain from eating or drinking (except water) for a period of 20 hours prior to the onset of the experiment. Participants were randomly asigned to one of two groups?the hungry group or the satiated group?and were asesed for three sesions. Those asigned to the hungry group were provided a meal before their first sesion but were not given any food for the next two, resulting in the following abstinence periods (in hours) since their initial meal: 0, 6, and 20. Participants asigned to the satiated group underwent the same procedure except that they were provided meals before each of their three sesions. The results showed that hungry participants had a bias to overrate the luminance of the food pictures, whereas satiated participants did not; this efect became more pronounced as the abstinence period grew longer. Collectively, the results suggested that the motivational efects of need afected the perception of the need-related object. In Experiment 2, the generalizability of the first experiment?s results was asesed by applying the same procedure to thirst-induced participants judging the luminance of thirst-related objects. A total of 48 participants were recruited who al agreed to abstain from consuming food or liquids of any kind for at least 8 hours prior to the start of the experiment. Each participant underwent four experimental sesions, each separated by approximately 2.5 hours. Thus, each 7 participant was asesed at 0, 2.5, 5, and 7.5 hours after last consuming any food or liquid. Participants were randomly asigned to one of four groups. Those asigned to either Group I or II were permited to eat and drink without restriction after beginning the first sesion. The only diference that existed betwen the two groups was that the same pitchers and glases of water that appeared in the slides were also present on an adjacent table for participants in Group I but were absent for participants in Group II. The condition diferences betwen Groups III and IV were the same as the condition diferences betwen Groups I and II, respectively, except that participants in Groups III and IV were not permited to eat or drink after beginning the first sesion. The aforementioned manipulations thus produced the following conditions: Group I, which was satiated with the need-related objects present; Group II, which was satiated with the need-related objects absent; Group III, which got increasingly thirstier with the need-related objects present; and Group IV, which got increasingly thirstier with the need-related objects absent. Preliminary analyses revealed that need-related object presence was neither significant as a main efect nor as an interaction with any other factor (i.e., satiation and sesion). As a result, need-related object presence was collapsed across subjects in the analysis for luminance matching acuracy. As in Experiment 1, increasing need (thirst) produced greater overestimates of the luminance of need-related objects (pitchers and glases of liquids), supporting the generalizability of the results found in Experiment 1. In Experiment 3, the authors sought to investigate whether any object, be it need-related or not, could produce the same efect. That is, does need bias luminance matching for any general object or for need-related objects only? To addres this question, the efect of need deprivation on the luminance matching of need-related objects was compared with its efect on the luminance matching of homogenous color fields. The slides that were used in Experiment 3 were 8 the same as those used in Experiment 2 except for the addition of six slides. These additional slides consisted of the following color fields: red, green, blue, orange, blue-green, and yelow. A total of 48 participants were recruited who al agreed to abstain from consuming food or liquids of any kind for at least 8 hours prior to beginning the experiment. Each participant underwent four sesions, with the first three carried out 4 hours apart and the fourth following the third by 5 minutes. Participants were randomly asigned to one of four groups. Those asigned to Groups I and II were permited to eat and drink without restriction during the course of the experiment. The diference betwen the two groups was that those in Group I were asked to match the luminance of the color slides, whereas those in Group II were asked to match the luminance of both the color slides and the need-related object slides. The treatment conditions of Groups III and IV were identical to Groups I and II, respectively, except that al participants were prohibited from eating or drinking during the time that spanned the first three sesions. The results showed that increasing need (thirst and hunger) produced greater overestimates of the luminance of need- related objects, whereas no such bias was present when matching the luminance of color slides. As in Experiment 2, the results of Experiment 3 further supported the study?s initial findings. The fourth and final experiment of Gilchrist and Nesberg?s (1952) study asesed whether the diference in luminance matching betwen color and need-related slides was due to the diferences in complexity of the slides themselves. As a result, Experiment 4 was performed with the following experimental parameters. A total of 12 participants were recruited who voluntered to abstain from consuming food or liquids of any kind for at least 8 hours prior to beginning the experiment. A within-subjects design was used such that every participant received the same treatment conditions, for which the experimental parameters were identical to what Group III of Experiment 3 received except that the ?control? slides were colorful landscapes (i.e., a mountain 9 range, a grove of trees in autumn, and a park lawn and shrubs) instead of homogenous color fields. As expected, the bias to overestimate luminance was not present for the color landscapes. The results of the study suggest that rising need produces an increasing bias to overestimate the luminance of need-related objects, and that this bias is restricted to these objects. In summary, the New Look approach to perception posits that visual perception is not just a function of optical variables, but is also a function of the organism?s current internal states, such as its needs, desires, and expectancies (Bruner & Goodman, 1947; Wit, Proffit, & Epstein, 2004). Acordingly, these influences on visual perception have been demonstrated empiricaly, as individuals have shown to perceive need-related objects as brighter and bigger compared to those unrelated to current need states (Bruner & Goodman, 1947; Gilchrist & Nesberg, 1952) Criticisms of the New Look Aproach After the initial surge of studies in the literature supporting the New Look approach, a growing number of researchers began chalenging its premise by highlighting specific methodological and conceptual problems, which caused the movement to be dormant in the literature for nearly a half century. One of the earliest critics of the New Look approach was Harold McCurdy (1956) who argued that schemas influence perception to a greater degree than do need and value. McCurdy conceded that values and needs may influence perception in ?some way? (p. 167); however, memory schemas for valued objects likely play a more decisive role in how such objects are perceived. To ilustrate his point, McCurdy offered a pointed critique of Burner and Goodman?s (1947) coin study. Acording to Bruner and his colleagues (e.g., Bruner & Goodman, 1947; Bruner & Postman, 1949), the progresively increasing bias to overestimate the sizes of coins of increasing value demonstrates that the symbolic value of objects afects estimates of size. McCurdy, however, argued that this interpretation was criticaly flawed, as it 10 appeared to ignore the fact that smaler (in size, not value) coins may be underestimated. The size of a dime, for example, is not only underestimated but is done so to a greater degree than either a penny or a nickel, even though the value of a dime exceds that of the others (Carter & Schooler, 1949). McCurdy hypothesized that the acuracy of size estimation for perceived objects is dependent upon the degree to which those objects belong to a definite schema. Contrary to intuition, he posited that size estimation acuracy would be lower for objects belonging to a definite schema relative to objects belonging to a les refined schema. McCurdy reasoned that schemas obviate the need to pay close atention to objects, thus leading to greater inacuracy. Indeed, his hypothesis was supported by a contemporaneous study (Bruner & Rodrigues, 1953), which found that estimates of size for coins improved in acuracy when the coins were present compared to when they were absent. Furthermore, estimates of size for cardboard discs, which presumably have les refined schemas than do coins, were even more acurate. Another major criticism of the perceptual defense and vigilance hypothesis has been referred to as the logical paradox. The paradox, which began to propagate in the literature in the early 1950s (e.g., Howie, 1952; Luchins, 1950), argued the following: if perceptual defense is truly perceptual in nature, then how is it that an individual can guard himself against an afectively negative stimulus without first perceiving it? Howie (1952) elaborated upon this criticism by elegantly arguing the following: ?To speak of perceptual defense is to use a mode of discourse which must make any precise or even inteligible meaning of perceptual defense impossible, for it is to speak of perceptual proces as somehow being both a proces of knowing and a proces of avoiding knowing? (p. 311). Erdelyi (1974) observantly pointed out that Howie made his argument by referring to ?proces? in singular form in relation to perception, thereby 11 implying that perception consists of a single proces that is dichotomously expresed?that is to say that stimuli are either perceived or not perceived. Viewed in this light, perceptual defense (and vigilance) cannot exist as it was originaly conceptualized. The paradox, however, ceases to maintain its credibility once perception is viewed within a multi-proces framework (e.g., an information-procesing model). For example, it may be the case that rudimentary characteristics of a given stimulus are briefly stored in a buffer and those that are likely to evoke negative emotional experiences are subsequently excluded from further procesing and thus from conscious perceptual experience (Erdelyi, 1974). Other critics of the New Look literature have argued that the apparent duality of the defense- vigilance efect cannot, by its very nature, be falsifiable. As noted earlier, perceptual defense refers to a relative increase in recognition threshold in response to emotional stimuli, whereas perceptual vigilance refers to a relative decrease in recognition threshold for such stimuli. Some researchers have found this duality unsetling given its post-hoc rationale for explaining threshold deviations?no mater which direction the deviation is observed to occur, a succesful finding of a perceptual bias can be reported. The isue of duality, however, never rose to become a prominent concern in the literature, as the manner in which the efect is expresed has been succesfully predicted in independent contexts (Carpenter, Wiener, & Carpenter, 1956; Chodorkoff, 1954; Eriksen, 1951, 1952, 1954; Hutt & Anderson, 1967; Lazarus, Eriksen, & Fonda, 1951; Mathews & Wertheimer, 1958; McGinnies & Adorneto, 1952; Moody, 1957; Singer, 1956; Spence, 1957; Stein, 1953). The basis of these studies stem from the idea that perceptual defense is asociated with personality diferences, and thus diferent modes of reacting to emotional stimuli (i.e., inhibition and vigilance). Others have gone so far as to propose a curvilinear relationship betwen sensitivity to afective stimuli and degree of 12 emotionality (e.g., Brown, 1961; Bruner & Postman, 1947). As a result, ?perceptual defense? has been often used as a generic term to describe both sensitivity elevation and inhibition in response to afective stimuli. A methodological isue in perceptual defense research that did gain early traction in the literature was the word-frequency problem (Howes, 1954; Howes & Solomon, 1950, 1951; Howie, 1952; Postman, 1953; Postman, Bronson, & Gropper, 1953; Solomon & Postman, 1952). Howes and Solomon (1950) were the first to bring this criticism to light, arguing that the perceptual defense efect was confounded by frequency of use diferences betwen taboo and afectively neutral words. The basis of their argument (Howes & Solomon, 1950, 1951) stemed from a series of scaterplots, graphing recognition thresholds against the logarithm of word frequencies, which yielded a correlation coeficient of -0.70. Acording to Howes and Solomon, this finding suggested that frequency diferences could simulate perceptual defense efects due to the lower frequency of use of taboo words relative to afectively neutral words. However, the word frequency values that were used to base this evaluation on were taken from a teacher?s reference aid on developmentaly appropriate word span among schoolchildren, which may have represented an inadequate source since it may have greatly underestimated the frequency of taboo words used among a college population. As a result, Eriksen (1963) conducted a study to ases the adequacy of these word frequencies among college students by having participants define each of the words from the original list. Thus, adequacy of the original word frequency values was determined by the percentage of participants that could correctly define each word. For afectively neutral words, the correlation betwen word frequency and the number of correctly-given definitions was 0.57; for taboo words, the correlation was only 0.03, suggesting that the words chosen as ?taboo? were indeed misleading and inadequate in describing their true 13 frequency of use. Compounding the problem even further, the word frequency values of the original word list went unchalenged by many, leading to the continued use of the flawed word list (Erdelyi, 1974). Yet another problem existed with the word-frequency criticism. Although Howes and Solomon (1950, 1951) reported correlations that plotted recognition thresholds against the logarithm of word frequencies, their interpretation of the results failed to consider the logarithmic transformation itself. For instance, Howes and Solomon (1951) argued in their paper that ?the probability of a word has an enormous efect on its visual duration threshold? (p. 401). This is simply not true, however, when the logarithmic transformation is taken into acount. Not only was the efect smal, but it was absent altogether throughout the majority of the frequency ranges that Howes and Solomon had examined. Upon closer examination of the original scaterplots, Erikson (1963) observed that practicaly no relationship existed betwen recognition threshold and word frequency within the range of 10-3,000 occurrences per milion. Thus, the ?enormous? efect that Howes and Solomon boasted about was only due to threshold diferences betwen very frequent and very infrequent words. This observation was further supported by perceptual defense and vigilance outcomes that have been found in studies controlling for word- frequency efects (e.g., Chapman & Feather, 1972; Dulany, 1957; Levy, 1958; Pustel, 1957; Sales & Haber, 1968). Another criticism of the perceptual defense literature was the expectancy-set argument (Freeman, 1954; Howie, 1952; Lacy, Lewinger, & Adamson, 1953; Luchins, 1950). Although not nearly as popular as the word-frequency criticism, the expectancy-set argument did generate some interest for a period of time (Cable, 1969; Forrest, Gordon, & Taylor, 1965). Those who championed the expectancy-set position argued that perceptual defense efects were largely the 14 product of participants? expectations of the afective quality of the stimuli. Luchins (1950) and others posited that perceptual defense outcomes could best be acounted for by expectancy-set based on two factors: (1) stimuli that are presented unexpectedly tend to have higher thresholds, and (2) subjects participating in a laboratory experiment do not generaly expect afectively negative stimuli to be presented in an otherwise benign and safe environment. Interestingly, this point of view posed an internal conflict within the New Look faction, as advocates of one New Look theme (the efect that expectancies has on perception) were critical of another New Look theme (the efect that motives has on perception). The question has not been whether expectations have an efect on thresholds, as an abundant amount of evidence has shown that they indeed do have an efect (e.g., Cable, 1969; Forrest, Gordon, & Taylor, 1965; Lacy, Lewinger, & Adamson, 1953; Postman, Bronson, & Gropper, 1953); but rather, the more important question to ask is whether expectancy sets prohibit motivations (e.g., wishes and desires) from influencing perception as wel. The need to addres this core isue was obviated by what became the extensive documentation of perceptual vigilance outcomes (Bootzin & Stephens, 1967; Chapman & Feather, 1972; Dorfman, 1967; Dulany, 1957; Levy, 1958; Sales & Haber, 1968), which in and of itself belied the expectancy-set argument as a plausible, alternative acount for explaining threshold changes to emotional stimuli. Furthermore, the expectancy-set hypothesis could not claim to be a more superior and parsimonious theoretical concept than perceptual defense. As Gibson (1941) noted in his review of set, the term has subsumed numerous concepts (e.g., mental set, preparatory set, goal set, motor set), thus representing ?practicaly everything?and therefore nothing? (Erdelyi, 1974, p. 7). This isue persisted until the 1960s when the concept of set was positioned within the framework of perceptual selectivity, with procesing strategies and encoding priorities playing critical roles for 15 the concept (e.g., Egeth, 1967; Haber, 1966). Viewed more broadly within the purview of perceptual selectivity, the concept of set becomes amenable to and compatible with perceptual defense, as it is merely another type of selectivity. Perhaps the most significant criticism of the perceptual defense efect is the response bias position. The response bias criticism has taken the form of three diferent categories. The first to be reported in the literature is referred to as the response suppresion hypothesis. Esentialy, the hypothesis posits that participants recognize afectively neutral and taboo words with equal competence, but require longer exposure durations to report the taboo words because they may cause embarrasment. To investigate the validity of this argument, Nothman (1962) had participants report afectively neutral and taboo words oraly and in writen form (a mode of reporting that was intended to reduce embarrasment). Results showed that recognition thresholds were significantly lower when the response method was in writen format compared to when it was oral, thus lending support to the response suppresion hypothesis. However, numerous studies have produced results to the contrary (e.g., Ruiz & Krauss, 1968; Zigler & Yospe, 1960). Thought of another way, the response suppresion hypothesis can be reformulated in terms of signal detection theory. Within this framework, the observer is equaly sensitive to afectively neutral and taboo words, but asumes a more stringent decision criterion to report taboo words relative to afectively neutral words, resulting in a perceptual defense-like efect. Findings from the few studies that have used this signal detection approach appear to dispute the response suppresion argument (e.g., Broadbent & Gregory, 1967; Chapman & Feather, 1972; Dorfman, 1967). The second form of the response bias criticism is known as the simple response bias. Early proponents of the simple response bias (e.g., Goldiamond & Hawkins, 1958; Goldstein, 1962) 16 argued that observers produce biased responses based on a probabilistic hierarchy influenced by such things as past learning history and frequency factors. Consequently, correct recognition is thought to be biased toward high probability stimuli, independent of stimuli properties. Like previous criticisms of perceptual defense, this particular hypothesis of the response bias has come under a lot of scrutiny. Some have doubted, for example, that this type of bias can have a significant impact on recognition when considering how large the vocabulary system is in the English language (e.g., Kempler & Wiener, 1964; Wiener & Schiler, 1960). As Kempler and Wiener (1964) have noted, ?why should Ss emit the particular word from several thousand likely words within the limits of the number of trials involved in a recognition task, if no cue is involved?? (p. 59). What?s more, many others have made known their own personal criticisms of the simple response bias (e.g., Brown & Rubenstein, 1961; Zajonc & Nieuwenhuyse, 1964). The third and final form of the response bias criticism has been termed the part-cue response-characteristic hypothesis. Advocates of the part-cue hypothesis speculate that some form of emotional input is initialy registered, even under imperfect presentational conditions. They further argue that the perceptual defense efect is expresed by way of so-caled response biases in the elaboration of such incomplete information. Some have argued, however, that the part-cue hypothesis is simply an explanation of perceptual defense rather than an absolute criticism of the efect (e.g., Erdelyi, 1974; Eriksen, 1963; Kempler & Wiener, 1963). Similarly, others have argued that the very idea that emotional input undergoes an elaboration proces is certainly not an argument that is incompatible with the concept of perceptual defense (Gregory, 1966). Indeed, it is known that perceptual phenomena as a whole (e.g., depth perception, context and contrast efects) involve not just registration but elaborative and synthesizing proceses as well (Anstis & Mather, 1985). 17 In summary, after initialy enjoying widespread support in the literature, a number of ostensible methodological and conceptual problems levied against the New Look perspective were brought to light, leading to its temporary dormancy in the literature. Over time, however, it was found that the evidence used to support these criticisms were methodologicaly flawed in their own right, and thus were subsequently discredited. As a result, this provided an opportunity for the New Look perspective to regain its status in the literature. Curent Directions in the New Look Literature As the diferent major criticisms of the New Look approach to perception became debunked over time, it gave rise to a second wave of New Look research that represented a significant extension of the existing literature. Researchers began acknowledging the utility of such research, exploring its premise through the prism of novel applications and contexts. Here, I review some of the representative literature of this second wave. One study, for example, conducted three separate experiments demonstrating the degree to which efort plays a role in perceiving distance (Proffit, Stefanucci, Banton, & Epstein, 2003). In the first experiment, participants were asked to make multiple distance judgments, in which one group was left unencumbered and the other was required to wear a heavy backpack while making these judgments. Distance judgments were made in a flat, university field; cones set up in a radial patern around the participants were used to mark the predetermined distances that ranged from 1 to 7 m from the observer. The results indicated that those who were required to wear the backpack judged the distances to be significantly longer compared to those who were left unencumbered. In the second experiment, anticipated walking efort was manipulated in a diferent fashion. Experiment 2 represented a systematic replication of an earlier study (Durgin et al., 2000), which 18 found that a visual-motor afterefect could be produced from walking on a treadmil without optic flow. In the study performed by Durgin et al. (2000), optic flow was manipulated by having participants walk on a treadmil while wearing a head-mounted display, showing either a static or moving virtual environment. Once off the treadmil, participants were blindfolded and were instructed to walk in place until no other unatended motion was produced. Participants who did not experience optic flow were more likely to walk forward at a greater distance when atempting to remain in place than those who did experience optic flow. In this study, however, the actual speed that had been set on the treadmil was not commensurate with the rate of optic flow that was experienced form the virtual environment. As a result, Proffit et al. (2003) performed a systematic replication by equating the rates of optic flow with that of actual walking speed. Despite this modification, the authors obtained a similar result, suggesting that participants? visual-motor system may have operated to anticipate a similar asociation betwen continued walking efort and zero optic flow. Proffit et al. reasoned that this afterefect ?should also cause the system to anticipate an increase in the forward walking efort required to walk to a target? (p. 110). Thus, if anticipated walking efort does indeed affect distance judgments, then the visual-motor afterefect should lead to higher estimates of perceived egocentric distance, which was the premise underlying Experiment 3. In the third and final experiment of the Proffit et al. (2003) study, participants made their distance judgments before and after treadmil adaptation. For pre-adaptation distance judgments, participants were asked to stand in a halway and make three egocentric distance estimates in relation to a cone that was placed at 6, 8, and 10 m; a 1-ft ruler was used as a reference during these judgments. Participants were blindfolded while the distances of the cones were adjusted. During adaptation, participants wore a head-mounted display while walking on a treadmil for a 19 3-minute duration. At the conclusion of the adaptation period, participants were led off the treadmil and were blindfolded to replace the head-mounted display. For post-adaptation distance judgments, participants were asked to make a single egocentric distance estimate in relation to a cone that was placed 8 m from the observer. Consistent with their hypothesis, the authors found that participants provided greater distance estimates after having experienced no optic flow than when optic flow was present. Collectively, the results across the three experiments demonstrated that anticipated walking efort influences perceived egocentric distance, underscoring the functional qualities underlying perceptual experience. A follow-up study was conducted by Wit, Proffit, and Epstein (2004), which found that perceived distance is influenced by anticipated efort only when the efort is asociated with an intended action that is relevant to the anticipated efort. Acordingly, the authors performed a series of experiments demonstrating this phenomenon. In Experiment 1, participants were placed in a flat, grasy field, standing in front of marked targets ranging in distance from 3 to 11 m from the observer. Half the participants were given a light bal and the other half was given a heavy bal. For each distance, participants were instructed to throw the bal as close as possible to the target three separate times. After completing the third throw, participants were asked to make an egocentric distance estimate to the target. Compared to those that threw the light bal, participants who threw the heavy bal provided significantly higher distance estimates for each target. In Experiment 2, participants were presented with the same set of targets and asked to perform two actions for each target: (1) throw either a light or heavy bal to the target and (2) adjust the distance betwen two poles (perpendicular to the egocentric plane of the target) to 20 match the egocentric distance to the target. Those who threw the heavy bal adjusted the distance betwen the two poles to be at a greater distance compared to those who threw the light bal. Similar to Experiment 2, participants in Experiment 3 were instructed to throw either a heavy or light bal up to three times for each target. After the last throw was made, participants were blindfolded, turned 180 degrees, and were asked to walk a distance that matched the egocentric distance to the original target. Although manipulating efort for throwing influenced distance judgments in the first two experiments, it was found not to influence walking blindfolded in the third experiment. Wit et al. (2004) hypothesized that the intended action that participants anticipated to perform influenced whether perceived distance would be distorted. Acordingly, Experiment 4 asesed this hypothesis by introducing an intention manipulation, which the authors defined as ?the action that the participants were anticipating performing imediately after making each distance judgment? (p. 584). Participants were randomly asigned to one of two groups. In each group, participants threw a heavy bal and made distance estimates for each target in a flat, grasy field. Participants asigned to one group were told beforehand that they would be given the same bal and asked to throw to each target with their eyes closed after making their original distance estimates, whereas those asigned to the other group were told beforehand that they would be blindfolded and asked to walk a distance that matched the egocentric distance to the target after making their original distance estimates. Although both groups underwent the same initial experience of throwing the heavy bal, only those that expected to blind-throw to the targets perceived them to be farther away than their actual distance compared to those that expected to blind-walk to the targets. Overal, the results of the study suggest that perception of egocentric distance is not just a function of the distance itself, but also is a function of the 21 intended action that is to be performed toward achieving the distal extent as wel as the efort asociated with it (Wit, Proffit, & Epstein, 2004). More recent studies of the second wave literature have re-visited the idea that motivational states can influence visual perception. Balcetis and Dunning (2006), for example, demonstrated that participants? interpretation of an ambiguous image is guided by their preferences. In the study?s first experiment, participants were seated at a table and presented with two beverages: freshly squeezed orange juice (the desired beverage) and an odorous ?veggie smoothie? (the undesired beverage). Participants were then told that a computer program would determine which of the two beverages they would be asked to drink. For half the participants, the number 13 (with the numbers spaced together to make it also look like the leter ?B?) would indicate that they had been asigned to drink the orange juice and the leter ?B? would indicate that they had been asigned to drink the veggie smoothie. For the other half of participants, the opposite leter/number asignments were provided. The authors found that participants reported seing the stimulus that would provide them with the more desired beverage. A systematic replication of the first experiment using a diferent ambiguous stimulus (an image that could be perceived as either a seal or horse) produced a similar result (Balcetis & Dunning, 2006, Experiment 2). Balcetis and Dunning (2006), however, conceded that a competing explanation existed. That is, participants may have been aware of both interpretations at the time they viewed the stimulus and had simply reported seing what they knew would result in receiving the more desirable beverage. As a result, the authors performed a third experiment to ensure that this was not indeed the case. To ases this competing explanation, participants? initial eye movements were recorded as a means of using an implicit measure given that they occur outside of conscious procesing (Alopenna, Magnuson, & Tanenhaus, 1998; Richardson & Spivey, 2000). Similar to 22 Experiment 2, participants were asked to report whether they had sen a seal or horse after being told which would result in having to drink the orange juice and veggie smoothie. Next, they were shown two phrases on a computer screen??farm animal? and ?sea creature??and examined which of the two received the participant?s first sacade. Consistent with the authors? expectations, participants? first sacade tended to be directed toward the word stimulus that corresponded to their original self-report. This result was confirmed when a lexical decision task replaced the eye movement measure in a subsequent experiment (Balcetis & Dunning, 2006, Experiment 4). Taken together, the results provided converging evidence that perceiving ambiguous visual stimuli is influenced by people?s motivational states. Extending upon their 2006 study, Balcetis and Dunning (2010) investigated the influence of desirable objects on distance perception. In this study, the authors hypothesized that objects serving imediate goal-states would be sen as both more desirable and closer in proximity to the observer, reasoning that individuals perceive desirable objects in this manner because such a perceptual experience motivates approach behaviors that wil aid in object atainment. Acordingly, a series of studies were performed confirming this hypothesis. In Study 1, participants were randomly asigned to one of two groups: a thirsty condition or a quenched condition. Those asigned to the thirsty condition consumed a single serving of pretzels (a high sodium food), whereas those asigned to the quenched condition were asked to consume as much water as they wanted from four 8-oz servings of water. Al participants were then seated at a table with a water bottle placed on the far end, 36 in. away. On a form provided to them, participants recorded how long it had been since they last consumed a beverage. In addition, participants indicated on a 7-point Likert scale (1) how thirsty they were and (2) how appealing they found the water bottle to be. Participants were then given a 1-in. reference line and were 23 asked to make an egocentric distance estimate to the water bottle. The following results were found: (1) no significant diference was found betwen those in the thirsty and quenched conditions with respect to how long it had been since a beverage was last consumed; (2) those in the thirsty condition did indeed rate their level of thirst to be significantly higher than those in the quenched condition, thereby ensuring that the manipulation of inducing level of thirst produced its intended efect; (3) those in the thirsty condition rated the water bottle to be significantly more desirable than those in the quenched condition; and (4) participants in the thirsty condition perceived the water bottle to be significantly closer compared to participants in the quenched condition. In two subsequent studies, action responses involving other desirable objects were asesed (Study 3a and 3b). Participant action responses involved the manipulation of either an object (Study 3a) or the self (Study 3b) to atain a target distance. In each case, an action response was performed that was consistent with perceiving the desirable object as closer relative to a les desirable object. Balcetis and Dunning (2010) demonstrated how desirability could influence the perceived distance of an object that has the capacity to satisfy an imediate physiological need. The authors argued that this perceptual bias serves to motivate the organism toward goal-directed action of acquiring the object. Conversely, undesirable objects that are non-threatening may be perceived as farther away than desirable objects as a way to produce the perception of a les unpleasant state. However, as Balcetis and Dunning noted, this may be situational. If an individual is confronted with an undesirable object that poses an actual, imediate threat (e.g., a poisonous snake nearby), then one may perceive the object to be closer than it?s actual distance to encourage the organism to engage in escape behavior. 24 But what about undesirable objects that only pose a perceived (but not actual) threat? Phobic individuals tend to overestimate the threat value of phobia-related stimuli (Beck & Clark, 1997). Overestimating the likelihood and severity that a particular situation wil be threatening often produces false catastrophic expectations of iminent danger, even in cases when the situation may be innocuous. With an increased sense of danger, anxious individuals may be more likely to perceive phobia-related stimuli as being closer than non-anxious individuals given that closer (threatening) objects, in general, are more likely to threaten the survival of an organism than are more distal objects. To ases this hypothesis, Cole, Balcetis, and Dunning (2013) performed a study in which they brought participants into a room that had a semi-contained (using a tray) live tarantula on the table. Participants stood at a fixed distance from the tarantula and were asked to report on a Likert scale how threatened/frightened and disgusted they felt as wel as to estimate their egocentric distance to the tarantula. Cole et al. found that participants saw the tarantula as physicaly closer with increasing levels of perceived threat; ratings of disgust, however, had no bearing on egocentric distance estimates. Background on Specific Phobia Specific phobia is characterized by an excesive and persistent fear of a particular object or situation that is disproportionate to the actual threat value of the situation. Fear asociated with the phobia produces marked distres and/or functional impairment?academic, occupational, or social?resulting from the avoidance or anxious anticipation of encountering the phobic stimulus (American Psychiatric Asociation, 2000). Specific phobia is one of the most common disorders, with an estimated lifetime prevalence of 12% (Kesler, Berglund, Demler, Jin, & Walters, 2005); 25 75% of these individuals also experience at least one other phobia (Curtis, Magee, Eaton, Witchen, & Kesler, 1998). A number of approaches to studying specific phobia have taken hold in the literature, many of which have been guided by the cognitive model of anxiety. First developed by Beck, Emery, and Greenberg (1985), the cognitive model of anxiety is based on the notion that the misperception of innocuous stimuli as threatening or dangerous is a central feature of anxiety disorders. In addition to selectively procesing information related to threat, anxious individuals also underrate their personal capacities to cope as wel as the safety features present in their environment. Furthermore, the cognitive model posits that anxiety involves a complex interaction of physiological, behavioral, afective, and cognitive changes (Beck et al., 1985). At the physiological level, changes arise with increased sympathetic activation to prepare the organism for fight or flight. At the behavioral level, organisms: (a) take action by escaping or fighting, and (b) minimize risk-taking behavior to maximize safety. At the afective level, organisms experience felings of fear and apprehension. Lastly, at the cognitive level, anxiety involves: (a) abstract symptoms such as cognitive distortions, recurring automatic thoughts, and fear-related beliefs; (b) sensory-perceptual symptoms such as hypervigilance; and (c) cognitive dificulties such as problems with concentration and reasoning. Various methods have been used to examine these changes, including those based on cognitive-experimental paradigms, neuroimaging techniques, self-report instruments, and psychophysiological measures. Present Study The studies performed by Balcetis and Dunning (2010) as wel as Cole et al. (2013) ilustrated nicely how approach and escape motivation, respectively, influence perception of egocentric distance to objects eliciting those motivations. However, these studies were not 26 without their own limitations. For instance, though Balcetis and Dunning (2010) observed participants performing an action response to a desirable object that was congruent with a motivation to approach the object, no asociation (i.e., correlation) was reported betwen degree of visual perceptual bias and extent of the action response. Perhaps no such asociation was found, in part, because the action response required of participants involved a specific goal (e.g., adjusting one?s egocentric distance to an object until a specified distance was reached) rather than simply moving in relation to the object in isolation of any other concurrent goal. By removing extraneous goals from the action response, it may serve to beter isolate a behavioral response that is more directly influenced by approach motivation, thus making it easier to find an expected relationship betwen degree of biased visual perception and extent of physical action. In the Cole et al. (2013) study, no action response was asesed for, thus precluding any examination of whether degree of biased visual perception for a threatening object bears a relationship to the magnitude of the asociated action response. The present study sought to discover an asociation betwen degree of biased visual perception and extent of a relevant action response by performing the following two experiments. In Experiment 1, relevant modifications to Study 1 of Balcetis and Dunning (2010) were made to examine the influence of approach motivation on visual perception, and whether these perceptions afect action responses in a direction congruent with this motivation, by comparing thirsty and quenched individuals. Increased desirability should not only lead thirsty individuals to perceive the water bottle to be closer in distance but to be larger in height (given that closer objects appear bigger in size than more distal objects) as wel compared to quenched individuals; and that this perceptual bias should also influence the action response of thirsty individuals in a direction congruent with this increased desire to approach the water bottle. Here, 27 behavior influenced by approach motivation was asesed by comparing participants? step-back distance from the edge of the table before and after thirst (or thirst satiation) was induced while viewing the water bottle that was placed on the table. If biased visual perception influences physical action, then thirsty individuals should take a smaler step back from the edge of the table relative to their baseline distance than quenched individuals. Furthermore, the closer the water bottle is perceived?reflecting greater desirability?the shorter the distance that participants should step away from the water bottle. In Experiment 2, the asociation betwen degree of biased visual perception and extent of a relevant action response was examined by comparing spider-tolerant and spider-fearful individuals within the context of both approach and escape motivation, with the later receiving particular emphasis. For this experiment, participants were asked to make size (in length) and distance estimates to objects of varying levels of desirability to the observer. These objects included a $50 gift card, which participants were told beforehand that they would have a chance to win at the conclusion of the study (desirable condition); a busines card (neutral condition); a contained tarantula (undesirable fear-relevant condition); and apparent feces (undesirable fear- irrelevant condition). In addition, the same step-back response measure from Experiment 1 was used for each object/condition to ases for action response magnitude. Afterwards, participants completed two spider-related questionnaires?the Fear of Spiders Questionnaire (FSQ; Szymanski & O?Donohue, 1995) and the Spider Questionnaire (SPQ; Klorman, Werts, Hastings, Melamed, & Lang, 1974); the FSQ was used to diferentiate spider-fearful from spider- tolerant participants given its greater sensitivity in detecting diferences betwen phobic and non- phobic samples than the SPQ. The purpose of administering the SPQ, on the other hand, was to examine which of the two questionnaires beter correlates with perceptual judgment acuracy for 28 distance and size as wel as with the step-back response, which has not been previously investigated in the literature. For Experiment 2, escape motivation should diferentialy influence spider-fearful and spider-tolerant individuals in relation to perceiving the distance and size of the contained tarantula, which in turn should diferentialy afect their respective action responses. Because spider-fearful individuals wil be expected to perceive a greater level of threat toward the contained tarantula, they wil also have a greater motivation to escape the situation compared to spider-tolerant individuals. Thus, spider-fearful individuals relative to spider-tolerant individuals should (1) perceive the contained tarantula as physicaly closer and bigger (i.e., longer); (2) take a bigger step away from the contained tarantula; and (3) take a bigger step away from the contained tarantula the closer, bigger, and more threatening it is perceived. In addition, if the FSQ is indeed beter at discriminating betwen phobic and non-phobic samples, then participant scores on the FSQ should beter correlate with perceptual judgment acuracy for distance and size than the SPQ. No group diferences are expected for perceptual judgment acuracy and the step-back response involving the other three objects. Both spider-fearful and spider-tolerant individuals should perceive the gift card as closer in egocentric distance and bigger in size compared to the busines card and apparent feces, given its expected value as a desirable object. Overarching Purpose and Potential Implications The overarching purpose of the present study is to examine how approach (and escape) motivation, and thus the adaptability of engaging in such behaviors, influences visual perceptual judgments and subsequent action responses within the context of spider phobia. By manipulating approach and escape motivation in this manner, we should se perceptual distortions that are commensurate with this degree of motivation. If there indeed is a relationship betwen degree of 29 spider-related fear and perceptual distortion, this may have clinical implications for how phobic individuals interpret (or rather, misinterpret) the threat value of phobia-related stimuli. That is, with greater perceptual distortions, the more likely it wil be that phobic individuals wil avoid such stimuli, thus further sustaining the maintenance of their anxiety. Furthermore, comparing how wel the FSQ and SPQ predict the magnitude of these perceptual distortions and step-back responses can help to inform the relative clinical utility of each measure. If one measure is found to be a significantly beter predictor over the other, the superior measure may serve to beter ases treatment progres, as reductions in perceptual distortions and escape behavior should be asociated with reductions in anxiety. 30 II. Experiment 1 Method Participants Ninety-four undergraduate students (M age = 19.64 years, SD age = 1.15 years; 77 female) seking to earn extra credit for a psychology course were recruited, with 47 participants in each condition. Materials Each pretzel serving consisted of two 1.5-oz. packages of Snyder?s of Hanover? Mini Pretzels, constituting a total of 30% of one?s daily intake of sodium. Al water bottles used in the experiment were 16.9-oz. bottles of Der Park? water (height: 7.75 in.); labels for al water bottles were removed. Design and Procedure Participants stood at the edge of a table (that was marked by a tape placed on the floor) from a water bottle placed 36 in. away. Participants were instructed to stand on the tape such that the toe of their shoes was placed at the top edge of the tape. After taking this position, participants were told to take one step back while looking at the water bottle. The experimenter then measured (in inches) their stepping distance, from the toe of their shoe to the top edge of the tape. This measurement represented the baseline stepping distance for each participant. Participants were then seated at the table. Those randomly asigned to the thirsty condition were told to consume two bags of pretzels, whereas those randomly asigned to the quenched 31 condition were told to consume as much water as they wanted from two bottles of water at room temperature. While consuming water or pretzels, participants were given a form and asked to record how many minutes it had been since they last ate and consumed a beverage. After consumption, participants used the back of the same form to indicate on separate 7-point Likert scales how thirsty they felt and how appealing they found the bottle of water placed in front of them. Participants were then given a 1-in. reference line and were asked to record their egocentric distance estimate to the water bottle as wel as their estimate of its height, both given in inches. Next, participants were asked to stand on the tape and take one step back while looking at the water bottle. The measurement of their stepping distance was again taken. Afterwards, participants sat back at the table and were instructed to have the experimenter adjust the distance of the water bottle until they perceived an egocentric distance of 72 in (this task from this point forward wil be referred to as ?adjusted distance?). This was acomplished by the folowing: (1) the experimenter first asked each participant if the object should be moved toward or away from them; (2) while the object was in motion, they were instructed to tel the experimenter, ?stop,? once the object was perceived to be 72 in. away; (3) afterward, participants were asked if the distance of the object needed to be further adjusted; and (4) if so, steps 1-3 were repeated in sequence until participants reported that no further adjustments were needed. Participants were then debriefed and thanked for their time. Results Manipulation Checks Separate independent-samples t tests confirmed that participants in the thirsty and quenched groups did not significantly difer in the amount of time since they last consumed a beverage (M Thirsty = 104.6, SD Thirsty = 206.3; M Quenched = 103.83, SD Quenched = 194.16), t(92) = .02, p = .99; 32 or food (M Thirsty = 168.17, SD Thirsty = 264.56; M Quenched = 167.06, SD Quenched = 210.94), t(92) = .02, p = .98. In addition, participants who consumed pretzels reported feling more thirsty (M = 5.66, SD = 1.15) than those who consumed water (M = 1.64, SD = 0.92), t(92) = 18.75, p < .001, d = 4.08. As a result, participants in the thirsty condition perceived the water bottle to be more desirable (M = 6.02, SD = 1.22) than those in the quenched condition (M = 2.62, SD = 1.29), t(92) = 13.1, p < .001, d = 2.71. Perceptual Judgment Acuracy Estimates of egocentric distance, height, and adjusted distance involving the water bottle were converted to acuracy scores by subtracting the actual value of each from their respective perceived estimates, with negative scores indicating that the water bottle was perceived as closer or smaler than its actual value and positive scores indicating that the water bottle was perceived as farther or bigger than its actual value. Relative to participants in the quenched condition, those in the thirsty condition perceived the water bottle as closer in egocentric distance, replicating Balcetis and Dunning (2010). This result was confirmed by the following set of analyses. A one-way multivariate analysis of variance (MANOVA) was performed to ases perceptual judgment acuracy for egocentric distance, water bottle height, and adjusted distance betwen thirsty and quenched individuals. The efect of group was significant, F(3, 90) = 4.11, p < 0.01. Subsequent tests of betwen-subjects efects revealed that this efect was driven by diferences in egocentric distance estimates, F(1, 92) = 6.31, p < 0.02, ? p 2 = 0.64; rather than by diferences in height estimates, F(1, 92) = 1.63, p > 0.2; and adjusted distance estimates, F(1, 92) = 1.35, p > 0.2. Figures 1, 2, and 3 ilustrate perceptual judgment acuracy for egocentric distance, water bottle height, and adjusted distance, respectively. 33 Action Response Because individual diferences in height can afect a person?s stepping distance, action responses of participants were converted to percentages by taking participants? step-back distance from the edge of the table after thirst (or thirst satiation) was induced and dividing it by their baseline distance, then multiplying this quantity by 100 (se Figure 4 for results). Thirsty individuals took a smaler step back from the water bottle relative to their baseline (M = 95.58, SD = 19.97) compared to quenched individuals (M = 106.95, SD = 20.92), as confirmed by a one-way ANOVA, F(1, 92) = 7.23, p = 0.008, ? p 2 = .07. Furthermore, the closer the water bottle was perceived, the shorter the distance that participants stepped away from the water bottle relative to their baseline distance, r(94) = 0.37, p < .001. Discussion Relative to participants in the quenched condition, those in the thirsty condition perceived the water bottle as closer in distance, replicating Balcetis and Dunning (2010). In turn, this perceptual bias afected participants? action responses in a direction congruent with their degree of approach motivation?individuals in the thirsty condition took a smaler step back from the water bottle relative to their baseline distance compared to individuals in the quenched condition. The closer the water bottle was perceived, the shorter the distance that participants stepped away from the water bottle relative to their baseline, suggestive of an increased desire to approach the water bottle. To our knowledge, the present study is the first to demonstrate a linear asociation betwen biased visual perception and behavior influenced by approach motivation. Contrary to our hypothesis, however, participants in the thirsty condition did not perceive the water bottle as larger in height than those in the quenched condition. This null finding may be due to the following. The water bottles that participants in the quenched group drank from were 34 the same as those used for making perceptual judgments. Although the labels of al the water bottles were removed to reduce familiarity cues, the identical form factor of the water bottles may have been sufficient enough to give quenched individuals an advantage over thirsty individuals for judging the height of the water bottle. Should this hypothesis be reexamined, using a container of water that is unfamiliar to participants would beter help determine whether the desirability of this object influences how big it is perceived. Thirsty and quenched participants also did not difer in their perceptual judgment acuracy for adjusted distance. This null finding may have been found because the experimenter, rather than the participants themselves, adjusted the distance of the water bottle. In an ideal scenario, participants would have direct control over the movement of the water bottle; however, this was not possible because it would require participants to get up from their seated position to do so. To compensate for this limitation, the experimenter made every efort to move the water bottle at a steady and consistent rate across participants by fixating away from the participant and water bottle. Even with these precautions in place, it could not be ensured that the water bottle was moved at a uniform rate across participants. Results of the present experiment support the notion that biases in visual perception for desirable objects exist to encourage the organism to engage in behaviors toward acquiring the object, as evidenced by participants taking a smaler step away from the water bottle the closer it was perceived. More importantly, these results demonstrate that the relationship betwen biased visual perception and behavior influenced by approach motivation exists along a continuum and thus can be explained in terms of magnitude, which would not be possible if the relationship were merely categorical. Acordingly, if the value of egocentric distance is known, one can use this information to help predict the extent of physical action that would be produced based on 35 this perceptual experience. The applicability of this predictive relationship should be explored in future studies. It is reasonable to think, for example, that this may offer clinicians an eficient method for generating a reinforcer preference list for child clients based on performing a series of simple perceptual judgment tasks. Other areas worth further exploration include the generalizability of the relationship betwen biased visual perception and behavior influenced by approach motivation (e.g., are greater biases in visual perception asociated with how quickly action responses are performed?) and whether a similar relationship exists for objects that motivate escape behavior, the later of which serving as an impetus for Experiment 2. 36 III. Experiment 2 Method Participant Selection Based on a power analysis, a total of 72 participants?36 in the spider-fearful group and 36 in the spider-tolerant group?were recruited in the final sample (M age = 19.89 years, SD age = 1.07 years; 60 female). Relevant parameters for this power analysis (e.g., expected heterogeneity, the correlation among the dependent measures) were determined by using pilot data as wel as those borrowed from a related study (Cole, Balcetis, & Dunning, 2013). Participants whose scores were in the top 15 percent for the cohort on the FSQ were identified as spider-fearful, whereas participants whose scores were in the bottom 15 percent for the cohort on the FSQ were identified as spider-tolerant; this criterion has been used in previous studies to diferentiate individuals with high and low spider-related fear (e.g., de Jong, Peters, & Vanderhalen, 2002; Gerdes, Pauli, & Alpers, 2009). Thus, a total of 240 participants were screened for the study. Measures The SPQ comprises 31 true-false items about fear of spiders. Estimates of internal consistency (Kuder-Richardson Formula 20) for the SPQ have been consistently high, ranging from 0.83 to 0.89 (Klorman et al., 1974). Appendix A shows the items listed on the SPQ. The FSQ is an 18-item questionnaire, which asks the respondent to indicate on a 7-point Likert scale how strongly they agree with each spider-related scenario listed; scores can range from 18 to 126 (Szymanski & O?Donohue, 1995). The FSQ aseses current functioning by 37 explicitly using the word ?now? for each scenario. The FSQ has shown excelent internal consistency (Cronbach?s alpha = 0.92) and reliability (split-half reliability coeficient = 0.89). Appendix B depicts the items listed on the FSQ. Design Al participants underwent the same procedure. Perceptual judgments were made for four objects: a $50 gift card (desirable condition), a busines card (neutral condition), a contained tarantula (undesirable fear-relevant condition), and a piece of apparent feces (undesirable fear- irrelevant condition). The order in which these objects were presented across participants was counterbalanced via Latin square. Each object was observed once and was placed on a table at one of the following distances from the observer: 36 in., 42 in., 48 in., or 54 in. These distances were determined through pilot testing with the following goal in mind: to create enough variability in the distances to minimize memorial anchoring of previous object placements while not varying them so significantly as to impair distance estimates for the more distal objects relative to the more proximal objects. The order of object distance was determined via a random number generator with replacement such that each distance position was occupied exactly once per participant. In addition, each object was oriented the same way across al participants. The length of each object was defined to participants based on the following parameters. The length of the gift card and busines card was defined as the distance from the left edge of the object to the right edge. Similarly, the length of the apparent feces was defined as the distance betwen the two lateral ends of the object. Lastly, the length of the contained tarantula was defined as the distance betwen the ends of its longest leg and that of the corresponding leg on the other side of its body. 38 After the baseline step-back response was measured as wel as in betwen each object presentation, participants were escorted to an adjacent halway outside the room and were asked to solve a set of Sudoku problems. The purpose of this distracter task was to remove any perceptual cues that the participant could have otherwise relied upon for determining the next object?s distance relative to its predecesor. Procedure Participants first stood at the edge of a table that was marked by a tape placed on the floor. Participants were instructed to stand on the tape such that the toe of their shoes was placed at the top edge of the tape. After taking this position, participants were told to take one step back while looking straight ahead. The experimenter then measured (in inches) their stepping distance, from the toe of their shoe to the top edge of the tape. This measurement represented the baseline stepping distance for each participant. For each condition, participants were seated at the table and were provided a form in which they were asked to indicate on separate 7-point Likert scales how desirable, threatening, and disgusting they found the object. Participants were then given a 1-in. reference line and were asked to record their egocentric distance estimate to the object as wel as their estimate of its length, both given in inches. Next, participants were asked to stand on the tape and take one step back while looking at the object. The measurement of their stepping distance was again taken. Afterwards, participants sat back at the table and were instructed to have the experimenter adjust the distance of the object until they perceived an egocentric distance of 72 in. This was acomplished by the following: (1) the experimenter first asked each participant if the object should be moved toward or away from them; (2) while the object was in motion, they were instructed to tel the experimenter, ?stop,? once the object was perceived to be 72 in. away; (3) 39 afterward, participants were asked if the distance of the object needed to be further adjusted; and (4) if so, steps 1-3 were repeated in sequence until participants reported that no further adjustments were needed. At the conclusion of the experiment, participants were administered the SPQ and FSQ in a separate room. Participants were then debriefed and thanked for their time. Results Sample Characteristics Spider-fearful and spider-tolerant individuals did not significantly difer in age, as confirmed by an independent-samples t test, t(70) = 0.44, p = 0.66. Mean age was 19.94 (SD = 1.07) for spider-fearful individuals and 19.83 (SD = 1.08) for spider-tolerant individuals. The proportion of females was higher among spider-fearful individuals (86%) than among spider- tolerant individuals (81%); however, this diference was not statisticaly significant, as confirmed by an independent-samples t test, t(70) = 0.63, p = 0.53. Additionaly, spider-fearful individuals endorsed more spider fear-relevant symptoms on the FSQ than spider-tolerant individuals, as confirmed by an independent-samples t test, t(44) = 43.23, p < 0.001, d = 10.19. Mean FSQ score was 92.33 (SD = 9.16) for spider-fearful individuals and 22.03 (SD = 3.36) for spider-tolerant individuals. Similarly, spider-fearful individuals endorsed more spider fear- relevant symptoms on the SPQ than spider-tolerant individuals, as confirmed by an independent- samples t test, t(54) = 17.64, p < 0.001, d = 4.16. Mean SPQ score was 18.83 (SD = 4.68) for spider-fearful individuals and 3.19 (SD = 2.53) for spider-tolerant individuals. FSQ scores bore a strong relationship to SPQ scores among spider-fearful and spider-tolerant participants, r(72) = 0.93, p < 0.001. 40 Manipulation Checks Figures 5-7 ilustrate desirability, threat, and disgust ratings, respectively, as a function of group and object. As expected, spider-fearful individuals found the contained tarantula significantly les desirable than spider-tolerant individuals (M Fearful = 1.31, SD Fearful = 0.67; M Tolerant = 2.50, SD Tolerant = 1.54). As a result, spider-fearful individuals found the contained tarantula significantly more threatening than spider-tolerant individuals (M Fearful = 6.17, SD Fearful = 1.00; M Tolerant = 1.83, SD Tolerant = 0.85). As expected, no group diferences were found for ratings of disgust; rather, the objects themselves did difer in the level of disgust that was elicited. Specificaly, both the apparent feces (M = 5.69, SD = 1.27) and contained tarantula (M = 4.26, SD = 1.78) were rated significantly more disgusting than the gift card (M = 1.07, SD = 0.48) and busines card (M = 1.01, SD = 0.12); and the apparent feces was rated significantly more disgusting than the contained tarantula. Results for asesing diferences betwen spider- fearful and spider-tolerant individuals for ratings of desirability, threat, and disgust were confirmed by the following set of analyses. A 2 (Group: spider-tolerant, spider-fearful) x 4 (Object: gift card, busines card, apparent feces, contained tarantula) mixed design ANOVA was performed to ases ratings of desirability betwen spider-tolerant and spider-fearful participants. The efect of group was significant, F(1, 70) = 9.15, p = 0.003, ? p 2 = 0.12. Tests of within-subjects efects revealed that the factor of object was significant, F(3, 210) = 285.35, p < 0.001, ? p 2 = 0.80; as was the interaction betwen group and object, F(3, 210) = 4.20, p = 0.006, ? p 2 = 0.06. A subsequent simple-effects analysis revealed that this interaction was driven by diferences betwen the two groups in the desirability ratings of the contained tarantula, F(1, 210) = 22.56, p < 0.001, ? p 2 = 0.10; rather than by 41 diferences in the desirability ratings of the gift card, F(1, 210) = 1.25, p = 0.26; busines card, F(1, 210) = 0.77, p = 0.38; and apparent feces, F(1, 210) = 0.05, p = 0.82. A second 2 (Group: spider-tolerant, spider-fearful) x 4 (Object: gift card, busines card, apparent feces, contained tarantula) mixed design ANOVA was performed to ases ratings of threat betwen spider-tolerant and spider-fearful participants. The efect of group was significant, F(1, 70) = 127.82, p < 0.001, ? p 2 = 0.65. Tests of within-subjects efects revealed that the factor of object was significant, F(3, 210) = 322.35, p < 0.001, ? p 2 = 0.82; as was the interaction betwen group and object, F(3, 210) = 187.49, p < 0.001, ? p 2 = 0.73. A subsequent simple-effects analysis revealed that this interaction was driven by diferences betwen the two groups in the threat ratings of the contained tarantula, F(1, 210) = 753.42, p < 0.001, ? p 2 = 0.78; rather than by diferences in the threat ratings of the gift card, F(1, 210) = 0.001, p = 0.97; busines card, F(1, 210) = 0.0004, p = 0.98; and apparent feces, F(1, 210) = 0.003, p = 0.96. A third 2 (Group: spider-tolerant, spider-fearful) x 4 (Object: gift card, busines card, apparent feces, contained tarantula) mixed design ANOVA was performed to ases ratings of disgust betwen spider-tolerant and spider-fearful participants. The efect of group was not significant, F(1, 70) = 0.91, p = 0.34; as was the interaction betwen group and object, F(3, 210) = 0.17, p = 0.92. However, the main efect of object was significant, F(3, 210) = 322.18, p < 0.001, ? p 2 = 0.82. Tukey?s HSD post-hoc test revealed that both the apparent feces and contained tarantula were rated significantly more disgusting than the gift card and busines card (p?s < 0.001); and the apparent feces was rated significantly more disgusting than the contained tarantula (p < 0.001). Al other comparisons were not statisticaly significant (p?s > 0.9). Of important note, the perceived intensity of the afective quality of the undesirable threat- relevant (contained tarantula) and undesirable threat-irrelevant objects (apparent feces) was 42 equivalent. Ratings of threat for the contained tarantula did not difer from ratings of disgust for the apparent feces among spider-fearful participants, as confirmed by a paired-samples t-test, t(35) = 1.31, p = 0.20. Perceptual Judgment Acuracy Similar to Experiment 1, estimates of egocentric distance, length, and adjusted distance involving each object were converted to acuracy scores by subtracting the actual value of each from their respective perceived estimates, with negative scores indicating that the object was perceived as closer or smaler than its actual value and positive scores indicating that the object was perceived as farther or bigger than its actual value. Preliminary analyses revealed that both object order and object position were neither significant as a main efect nor as an interaction with any other set of factors (p?s > 0.4). As a result, object order and object position were collapsed across participants in the analyses for perceptual judgment acuracy. Figures 8, 9, and 10 ilustrate perceptual judgment acuracy for egocentric distance, object length, and adjusted distance, respectively. Spider-fearful participants perceived the contained tarantula as closer in distance and longer in size than spider-tolerant individuals, as confirmed by the following set of analyses. A doubly MANOVA was performed to ases perceptual judgment acuracy for egocentric distance, object length, and adjusted distance as a function of object (i.e., gift card, busines card, apparent feces, contained tarantula) and group (i.e., spider-tolerant and spider-fearful individuals). The efect of group was significant, F(3, 68) = 4.76, p = 0.005, ? p 2 = 0.17; as was the efect of object, F(9, 62) = 8.28, p < 0.001, ? p 2 = 0.55; and the interaction betwen group and object, F(9, 62) = 4.40, p < 0.001, ? p 2 = 0.39. 43 To interpret this interaction, four separate one-way MANOVAs were performed to ases perceptual judgment acuracy for egocentric distance, object length, and adjusted distance betwen spider-tolerant and spider-fearful individuals for each object. For the contained tarantula, the efect of group was significant, F(3, 68) = 15.85, p < 0.001, ? p 2 = 0.41. Subsequent tests of betwen-subjects efects revealed that this efect was driven by diferences in egocentric distance estimates, F(1, 70) = 17.49, p < 0.001, ? p 2 = 0.20; and object length estimates, F(1, 70) = 37.49, p < 0.001, ? p 2 = 0.35; rather than by diferences in adjusted distance estimates, F(1, 70) = 0.05, p = 0.82. No group diferences were found from the three other one-way MANOVAs, as the efect of group was not significant for the gift card, F(3, 68) = 0.12, p = 0.95; busines card, F(3, 68) = 1.49, p = 0.23; and apparent feces, F(3, 68) = 0.22, p = 0.88. As participants endorsed higher degrees of spider-related fear and perceived greater levels of threat, they perceived the contained tarantula as closer in egocentric distance and bigger (i.e., longer) in size (se Figures 11-16). Greater levels of perceived disgust, however, was not asociated with egocentric distance (se Figure 17) and length estimates (se Figure 18) for the contained tarantula. These results suggest that perceived threat rather than disgust biased visual perception for the contained tarantula, which was confirmed by the following analyses. As participants endorsed higher degrees of spider-related fear on the FSQ, they perceived the contained tarantula as closer in distance, r(240) = -0.25, p < 0.001; and longer in size, r(240) = 0.28, p < 0.001. A similar relationship was found betwen SPQ scores and egocentric distance estimates, r(240) = -0.22, p < 0.001; and betwen SPQ scores and length estimates, r(240) = 0.25, p < 0.001. The directionality of this relationship was also maintained with ratings of threat, as higher threat ratings for the contained tarantula were asociated with closer egocentric 44 distance estimates, r(240) = -0.18, p = 0.006; and bigger length estimates for the tarantula, r(240) = 0.30, p < 0.001. Ratings of disgust for the contained tarantula bore neither a relationship to egocentric distance estimates, r(240) = -0.06, p = 0.34; nor to length estimates for the tarantula, r(240) = 0.04, p = 0.51. The FSQ was not significantly beter at predicting egocentric distance estimates to the contained tarantula compared to the SPQ, which was confirmed by testing diferences betwen two dependent correlation coeficients, t(237) = 0.65, p = 0.52. Similarly, the FSQ was not significantly beter at predicting length estimates of the contained tarantula compared to the SPQ, t(237) = 0.91, p = 0.36. Action Response Similar to Experiment 1, action responses of participants were converted to percentages by taking participants? step-back distance from the edge of the table while viewing the object and dividing it by their baseline distance, then multiplying this quantity by 100. Compared to spider- tolerant participants, spider-fearful participants took a bigger step back from the contained tarantula relative to their baseline (se Figure 19). This result was confirmed by the following set of analyses. A 2 (Group: spider-tolerant, spider-fearful) x 4 (Object: gift card, busines card, apparent feces, contained tarantula) mixed design ANOVA was performed to ases the step-back response betwen spider-tolerant and spider-fearful participants. The efect of group was significant, F(1, 70) = 4.22, p = 0.04, ? p 2 = 0.06. Tests of within-subjects efects revealed that the factor of object was significant, F(3, 210) = 11.41, p < 0.001, ? p 2 = 0.14; as was the interaction betwen group and object, F(3, 210) = 7.37, p < 0.001, ? p 2 = 0.10. A subsequent simple-effects analysis revealed that this interaction was driven by diferences betwen the two groups in the 45 step-back response to the contained tarantula, F(1, 210) = 28.00, p < 0.001, ? p 2 = 0.12; rather than by diferences in the step-back response to the gift card, F(1, 210) = 0.19, p = 0.66; busines card, F(1, 210) = 0.17, p = 0.68; and apparent feces, F(1, 210) = 0.67, p = 0.41. The closer the contained tarantula was perceived by participants, the longer the distance that participants stepped away from the contained tarantula relative to their baseline distance (se Figure 20), r(240) = -0.20, p = 0.002. Step-back responses were related to degree of spider- related fear on the FSQ, r(240) = 0.37, p < 0.001; and SPQ, r(240) = 0.35, p < 0.001; as wel as ratings of threat, r(240) = 0.43, p < 0.001 (se Figures 21-23, respectively). These results suggest that greater levels of perceived threat were asociated with participants? taking a bigger step away from the contained tarantula. Greater levels of perceived disgust were asociated with step- back responses in a similar manner, albeit to a leser degree (se Figure 24), r(240) = 0.19, p = 0.003. The FSQ was not significantly beter at predicting the step-back response of participants to the contained tarantula compared to the SPQ, which was confirmed by testing diferences betwen two dependent correlation coeficients, t(237) = 0.63, p = 0.53. In addition, the closer the busines card was perceived by participants, the longer the distance that participants stepped away from the object relative to their baseline distance (se Figure 25), r(240) = -0.20, p = 0.002. Because spider-tolerant and spider-fearful participants did not difer in their egocentric distance estimates and step-back responses to the busines card, this suggests that this relationship resulted from the responses of participants who did not met criterion for either group. No significant asociations were found betwen egocentric distance estimates and step-back responses for the gift card, r(240) = -0.07, p = 0.31; and apparent feces, r(240) = 0.01, p = 0.93 (se Figures 26 and 27, respectively). 46 The bigger (i.e., longer) the contained tarantula was perceived by participants, the longer the distance that participants stepped away from the object relative to their baseline distance (se Figure 28), r(240) = 0.14, p = 0.03. However, no significant asociations were found betwen length estimates and step-back responses for the gift card, r(240) = -0.04, p = 0.54; busines card, r(240) = 0.03, p = 0.60; and apparent feces, r(240) = 0.10, p = 0.13 (se Figures 29-31, respectively). Discussion Compared to spider-tolerant individuals, spider-fearful individuals perceived the contained tarantula as closer in distance and longer in size. As participants endorsed higher degrees of spider-related fear (on the FSQ and SPQ) and perceived greater levels of threat, they perceived the contained tarantula as closer in egocentric distance and longer in size. Greater levels of perceived disgust, however, was not asociated with egocentric distance and length estimates for the contained tarantula. These results suggest that perceived threat rather than disgust biased visual perception for the contained tarantula. Furthermore, the FSQ was not significantly beter at predicting egocentric distance and length estimates to the contained tarantula compared to the SPQ, which suggests that neither instrument offered an advantage in predicting the magnitude of these given perceptual biases. The results further indicated that the observed biases in visual perception among spider- fearful individuals afected their action responses in a direction congruent with a motivation to escape. Compared to spider-tolerant participants, spider-fearful individuals took a bigger step back from the contained tarantula relative to their baseline. The closer and bigger the contained tarantula appeared to participants, the longer the distance that participants stepped away from the object relative to their baseline distance. Step-back responses were also asociated with degree of 47 spider-related fear on the FSQ, SPQ, as wel as ratings of threat and disgust. These results demonstrated that not only does a linear relationship exist betwen biased visual perception and behavior influenced by approach motivation (se Experiment 1) but that this relationship also exists betwen biased visual perception and behavior influenced by escape motivation. Just as with egocentric distance and length estimates, the FSQ provided no significant advantage at predicting the step-back response of participants to the contained tarantula compared to the SPQ. As expected, no group diferences were found for egocentric distance and length estimates for the gift card, busines card, and apparent feces. Surprisingly, however, the step-back responses of participants bore no relationship to their respective egocentric distance estimates to both the gift card and apparent feces. That is, as participants perceived the gift card as closer in distance, they did not take a smaler step away from it, which would be an expected action response to a desirable object. Though both spider- fearful and spider-tolerant individuals perceived the gift card as closer in egocentric distance and took a smaler step away from it (relative to their baseline) compared to the other three objects, the degree of biased perception for egocentric distance was not asociated with the extent of the physical action. A closer examination of the data suggests that no such asociation was likely found because the majority of the data points clustered together within a limited range, as shown in Figure 23. A similar observation was found for the apparent feces when examining the relationship betwen degree of biased perception for egocentric distance to the object and the extent of the respective step-back response, as shown in Figure 24. Similar to Experiment 1, the measure of adjusted distance did not produce any group diferences across the four objects. Furthermore, perceptual judgment acuracy for adjusted distance was nearly identical across the four objects, irrespective of group. Because the same 48 methodology was used from Experiment 1 for the adjusted distance task (i.e., the experimenter having direct control over the movement of the object), the question stil remains as to whether an efect would have been observed had there been a way for participants to directly control the movement of the objects while remaining in their seated position. Again, the experimenter made a concerted efort to move each object at a steady and identical rate across participants by fixating away from the participant and the given object. Nonetheles, these precautions could not produce the necesary amount of precision needed to significantly mitigate the limitations of this methodology. Should a similar measure of adjusted distance be implemented in future studies, using a virtual reality environment in which participants can manipulate the depth of an object using a button box may be worth exploring. If created realisticaly enough, one could also have participants perform other perceptual judgment tasks using the same virtual reality structure, such as those performed in this study. Results of the present experiment support the notion that biases in visual perception for objects eliciting perceived threat exist to encourage the organism to engage in escape-like behaviors, as evidenced by participants taking a bigger step away from the contained tarantula the closer and bigger it was perceived. Such a behavioral response mimics a typical flight reaction toward perceived danger. If running away is not a viable option, the next logical choice is to back up in order to increase one?s distance to the threatening object. This type of flight response is adaptive, as it provides the organism more time to react in the face of danger as wel as to look for alternative, unexplored ways to escape the situation, should they be available. In this way, having participants take a step back from the contained tarantula maps on wel to natural human behavior when confronted with perceived or actual threat. 49 IV. General Discussion The present study performed two experiments examining the influence of approach and escape motivation on visual perception, and whether these perceptions afect action responses in a direction congruent with these respective motivations, by comparing thirsty and quenched individuals (Experiment 1) as wel as spider-fearful and spider-tolerant individuals (Experiment 2). In each experiment, a linear relationship was found betwen the degree of biased visual perception and the extent of subsequent action responses. In Experiment 1, thirsty individuals took a smaller step away from the water bottle the closer it was perceived compared to quenched individuals. In Experiment 2, participants took a bigger step away from the contained tarantula (1) the closer it was perceived, (2) the bigger it was perceived, (3) the greater their endorsement of spider-related fear, and (4) the greater their level of perceived threat to the contained tarantula. From an evolutionary perspective, perceived proximity encourages action?approach in the case of desirable objects (e.g., gift card, water bottle for thirsty individuals) and escape in the case of threatening objects (e.g., contained tarantula among spider-fearful individuals). Indeed, this bias in visual perception is adaptive, as it motivates the organism toward goal-directed action that maximizes its chances of survival. For instance, if a primary reinforcer such as food is perceived, then the likelihood of its atainment wil be higher if the organism anticipates that it would require minimal physical efort, as would be the case if the source of food appeared closer than its actual distance. Likewise, if a threatening object such as a poisonous snake is perceived, then the likelihood of prompt action to escape (to ensure the survival of the organism) wil be 50 higher if the organism perceives greater iminent danger, as would be the case if the poisonous snake appeared closer than its actual distance from the observer. Of course, encountering a poisoning snake would produce such perceptual distortions in any typical population, as it represents an actual form of threat. What Experiment 2 asked was whether such perceptual distortions would stil be observed when the form of threat was perceived but not actual; and if so, how this would impact a subsequent action response relationaly. This study demonstrated that perceived threat was more than sufficient enough to produce these perceptual distortions, which impacted action responses in a linear fashion. From a broader perspective, this study revealed that visual perception and action responses are not mutualy exclusive proceses but rather are interconnected psychological events, which can be partialy predicted relationaly. Egocentric distance and size of an object may represent only two properties of many that could exist to explain this linear relationship betwen visual perception and physical action. If more environmental properties can be identified to produce greater predictive power of this relationship, then it may lend support to the notion that the perception-action link is actualy a shared dimension of the overal human experience?just as the theory of relativity posits with the space-time continuum. Although the present findings support a functional explanation, valid alternative explanations must be considered as wel. Previous research, for example, has found that one?s current afective state can influence how an object, unasociated with that afective state, is visualy perceived. One study found that participants who recaled a sad story prior to standing next to a hil perceived it to be steper than participants who did not have to recal a sad story (Riener, Stefanucci, Proffit, & Clore, 2011). Even though the hil itself was not responsible for producing a sad emotional state, the perception of it was nonetheles biased because of a 51 contiguous afective state that carried over to a diferent context. Thus, biased visual perception for an object can be observed independent of its functional value to the observer. The present study did not ases for participant mood prior to making their perceptual judgments and action responses. As a result, it cannot be determined whether afective states unrelated to the objects used in this study influenced any of the dependent measures that were examined. The narrowing of atention resulting from perceived threat may also influence perception for egocentric distance. Chajut and Algom (2003) found that the range of visual atention is disproportionately narrowed when threatening objects are perceived in the environment. This narrowing of atention, in turn, may lead individuals to perceive objects to be closer than their actual distance. A study that supported this notion found that hungry individuals who concentrated their focus to cookies perceived the food item to be 15% closer compared to individuals who had a wider range of focus (Balcetis, 2006). Thus, it stands to reason that spider- fearful individuals may have perceived the contained tarantula to be closer because their range of visual atention was narrowed relative to the apparent feces and busines card. Though one could view the narrowing of atention as an alternative explanation to the functional perspective of the New Look literature, this could also simply represent the physiological mechanism by which the functional response is expresed. From a global perspective, the present findings potentialy provide some practical applications in the clinical sphere. As stated previously, a linear relationship was found betwen degree of spider-related fear (as wel as degree of biased visual perception of the contained tarantula) and the step-back response to the contained tarantula. That is, the greater the endorsement of fear was to spiders, the more exaggerated participants? escape-like response (i.e., step-back response) was to the contained tarantula. Because greater tendencies to avoid/escape a 52 feared stimulus is asociated with long-term maintenance of the phobia, it stands to reason that such behavior can be a good indicator for which individuals may be at greater risk for noncompliance and/or atrition in exposure therapy. The maintenance of many anxiety disorders is quite robust, thus making atrition in exposure therapy always a possible concern. Treatment for Postraumatic Stres Disorder that includes both psychotherapy and pharmacotherapy, for example, has often been asociated with high atrition rates, ranging from 20 to 38% (Rauch, Eftekhari, & Ruzek, 2012). Given this clinical reality, it is imperative that clinicians beter identify through early detection those clients who are at greatest risk for treatment dropout. Toward this end, future research should examine whether the perception-action link asociated with escape motivation bears a relationship to atrition rates in psychotherapy for the treatment of specific phobia. If greater degrees of step-back responses to distorted visual perceptions of phobic stimuli are asociated with higher atrition rates, then one could potentialy use this data to help identify those clients who are especialy vulnerable to dropout from therapy. If these patients can be identified early on in therapy using such behavioral tasks used here, then it can provide the clinician with an opportunity to intervene a priori rather than be reactive post-hoc to treatment resistance/noncompliance. For example, this information could inform the clinician to spend more time using a motivational interviewing framework to help transition the client to the preparation stage of change in anticipation of client resistance. Such data may serve to help reduce atrition rates in exposure therapy contexts. 53 References Alopenna, P. D., Magnuson, J. S., & Tanenhaus, M. K. (1998). Tracking the time course of spoken word recognition using eye movements: Evidence for continuous mapping models. Journal of Memory and Language, 38, 419-439. American Psychiatric Asociation. (2000). Diagnostic and statistical manual of mental disorders. (4 th ed., Text Revision). Washington, DC: Author. Anstis, S. M., & Mather, G. (1985). Efects of luminance and contrast on direction of ambiguous apparent motion. Perception, 14, 167-179. Aronson, E., Wilson, T. D., & Akert, R. M. (2005). Social Psychology. New Jersey: Pearson Education, Inc. Asch, S.E. (1951). Efects of group presure upon the modification and distortion of judgment. In H. Guetzkow (Ed.), Groups, leadership, and men (pp.76-92). Pitsburgh, PA: Carnegie Press. Balcetis, E. E. (2006). Motivated visual perception: How we se what we want to se. Disertation Abstracts International: Section B. Sciences and Engineering, 67(7-B), 4153. Balcetis, E., & Dunning, D. (2006). Se what you want to se: Motivational influences on visual perception. Journal of Personality and Social Psychology, 91, 612-625. Balcetis, E., & Dunning, D. (2010). Wishful seing: More desired objects are sen as closer. Psychological Science, 21, 147-152. Beck, A. T., & Clark, D. A. (1997). An information procesing model of anxiety: Automatic and strategic proceses. Behaviour Research and Therapy, 35, 49-58. 54 Beck, A. T., Emery, G., & Greenberg, R. (1985). Anxiety disorders and phobias: A cognitive perspective. New York, NY: Basic Books. Bootzin, R. R., & Stephens, M. W. (1967). Individual diferences and perceptual defense in the absence of response bias. Journal of Personality and Social Psychology, 6, 408-412. Broadbent, D. E., & Gregory, M. (1967). Perception of emotionaly toned words. Nature, 215, 581-584. Brown, C. R., & Rubenstein, H. (1961). Test of response bias explanation of the word-frequency efect. Science, 133, 280-281. Brown, W. P. (1961). Conceptions of perceptual defense. British Journal of Psychology Monograph Supplements, 64 (No. 35). Bruner, J. S., & Goodman, C. C. (1947). Value and need as organizing factors in perception. Journal of Abnormal and Social Psychology, 42, 33-44. Bruner, J. S., & Postman, L. (1949). Perception, cognition, and behavior. Journal of Personality, 18, 14-31. Bruner, J. S., & Rodrigues, J. S. (1953). Some determinants of apparent size. Journal of Abnormal Social Psychology, 48, 17-24. Cable, D. G. (1969). Perceptual defense or set: A re-examination. Psychonomic Science, 16, 331- 332. Carpenter, B., Wiener, M., & Carpenter, J. T. (1956). Predictability of perceptual defense behavior. Journal of Abnormal and Social Psychology, 52, 380-383. Carter, L. F., & Schooler, K. (1949). Value, need, and other factors in perception. Psychological Review, 56, 200-207. 55 Chajut, E., & Algom, D. (2003). Selective atention improves under stres: Implications for theories of social cognition. Journal of Personality and Social Psychology, 85, 231-248. Chapman, C. R., & Feather, B. W. (1972). Modification of perception of clasical conditioning procedures. Journal of Experimental Psychology, 93, 338-342. Chodorkoff, B. (1954). Self-perception, perceptual defense, and adjustment. Journal of Abnormal and Social Psychology, 49, 508-512. Cole, S., Balcetis, E., & Dunning, D. (2013). Afective signals of threat increase perceived proximity. Psychological Science, 24, 34-40. Curtis, G. C., Magee, W. J., Eaton, W. W., Witchen, H. U., & Kesler, R. C. (1998). Specific fears and phobias: Epidemiology and clasification. British Journal of Psychiatry, 173, 212- 217. de Jong, P. J., Peters, M., & Vanderhalen, I. (2002). Disgust and disgust sensitivity in spider phobia: Facial EMG in response to spider and oral disgust imagery. Journal of Anxiety Disorders, 16, 477-493. Dorfman, D. D. (1967). Recognition of taboo words as a function of a priori probability. Journal of Personality and Social Psychology, 7, 1-10. Dulany, E., Jr. (1957). Avoidance learning of perceptual defense and vigilance. Journal of Abnormal and Social Psychology, 55, 333-338. Durgin, F. H., Banton, T. A., Waley, K., Proffit, D. R., Steve, J., & Lewis, J. (2000). Locomotor recalibration in a virtual world. Investigative Ophthalmology and Visual Science, 41(4), S799. Egeth, H. (1967). Selective atention. Psychological Bulletin, 67, 41-57. 56 Erdelyi, M. H. (1974). A new look at the New Look: Perceptual defense and vigilance. Psychological Review, 81, 1-25. Eriksen, C. W. (1951). Perceptual defense as a function of unaceptable needs. Journal of Abnormal and Social Psychology, 46, 557-564. Eriksen, C. W. (1952). Defense against ego-threat in memory and perception. Journal of Abnormal and Social Psychology, 47, 430-435. Eriksen, C. W. (1954). Psychological defenses and ego strength in the recal of completed and incompleted tasks. Journal of Abnormal and Social Psychology, 49, 45-50. Eriksen, C. W. (1963). Perception and personality. In J. M. Wepman & R. W. Heine (Eds.), Concepts of personality (pp. 31-62). Chicago: Aldine. Forrest, D., Gordon, N., & Taylor, A. (1965). Generalization of perceptual defense. Journal of Personality and Social Psychology, 2, 137-141. Freeman, J. T. (1954). Set or perceptual defense? Journal of Experimental Psychology, 48, 283- 288. Gerdes, A. B. M., Pauli, P., & Alpers, G. W. (2009). Toward and away from spiders: Eye- movements in spider-fearful participants. Journal of Neural Transmision, 116, 725-733. Gibson, J. J. (1941). A critical review of the concept of set in contemporary experimental psychology. Psychological Bulletin, 38, 781-817. Gilchrist, J. C., & Nesberg, L. (1952). Ned and perceptual change in need-related objects. Journal of Experimental Psychology, 44, 369-376. Goldiamond, I., & Hawkins, W. F. (1958). Vexierversuch: The log relationship betwen word- frequency and recognition obtained in the absence of stimulus words. Journal of Experimental Psychology, 56, 457-463. 57 Goldstein, M. J. (1962). A test of response probability theory of perceptual defense. Journal of Experimental Psychology, 63, 23-28. Gregory, R. L. (1966). Eye and brain. New York: McGraw-Hill. Haber, R. N. (1966). Nature of the efect of set on perception. Psychological Review, 73, 335- 351. Howes, D. H. (1954). A statistical theory of the phenomenon of subception. Psychological Review, 61, 98-110. Howes, D. H., & Solomon, R. L. (1950). A note on McGinnies? ?Emotionality and perceptual defense.? Psychological Review, 57, 229-234. Howes, D. H., & Solomon, R. L. (1951). Visual duration threshold as a function of word- probability. Journal of Experimental Psychology, 41, 401-410. Howie, D. (1952). Perceptual defense. Psychological Review, 59, 308-315. Hutt, L. D., & Anderson, J. P. (1967). Perceptual defense and vigilance: Prediction from the Byrne Scale of Represion-Sensitization. Psychonomic Science, 9, 473-474. Kempler, B., & Wiener, M. (1963). Personality and perception in the recognition threshold paradigm. Psychological Review, 70, 349-356. Kempler, B., & Wiener, M. (1964). Personality-perception: Characteristic response to available part-cues. Journal of Personality, 32, 57-74. Kesler, R. C., Berglund, P., Demler, O., Jin, R., & Walters, E. E. (2005). Lifetime prevalence and age-of-onset distributions of DSM-IV disorders in the National Comorbidity Survey Replication. Archives of General Psychiatry, 62, 593-602. Klorman, R., Werts, T. C., Hastings, J. C., Melamed, B. G., & Lang, P. J. (1974). Psychometric description of some specific-fear questionnaires. Behavior Therapy, 5, 401-409. 58 Lacy, O. W., Lewinger, N., & Adamson, J. f. (1953). Foreknowledge as a factor afecting perceptual defense and alertnes. Journal of Experimental Psychology, 45, 169-174. Lazarus, R. S., Eriksen, C. W., & Fonda, C. P. (1951). Personality dynamics and auditory perceptual recognition. Journal of Personality, 19, 471-482. Levy, L. H. (1958). Perceptual defense in tactual perception. Journal of Personality, 26, 467- 478. Luchins, A. S. (1950). On an approach to social perception. Journal of Personality, 19, 64-84. Mathews, A., & Wertheimer, M. (1958). A ?pure? measure of perceptual defense uncontaminated by response suppresion. Journal of Abnormal and Social Psychology, 57, 373-376. McCurdy, H. G. (1956). Coin perception studies and the concept of schemata. Psychological Review, 63, 160-168. McGinnies, E., & Adorneto, J. (1952). Perceptual defense in normal and schizophrenic observers. Journal of Abnormal and Social Psychology, 47, 833-837. Moody, H. L. (1957). Perceptual defense as revealed by normal and clinicaly referred subjects in responses to three clases of pictorial stimuli. Disertation Abstracts, 17, 1934. Nothman, F. H. (1962). The influence of response conditions on recognition thresholds for taboo words. Journal of Abnormal and Social Psychology, 65, 154-161. Postman, L. (1953). On the problem of perceptual defense. Psychological Review, 60, 298-306. Postman, L., Bronson, W. C., & Groper, G. L. (1953). Is there a mechanism of perceptual defense? Journal of Abnormal and Social Psychology, 48, 215-224. Proffit, D. R., Stefanucci, J., Banton, T., & Epstein, W. (2003). The role of efort in perceiving distance. Psychological Science, 14, 106-112. 59 Pusteli, T. E. (1957). The experimental induction of perceptual vigilance and defense. Journal of Personality, 25, 425-438. Rauch, S. A., Eftekhari, A., & Ruzek, J. I. (2012). Review of exposure therapy: A gold standard for PTSD treatment. Journal of Rehabilitation Research and Development, 49, 679-688. Richardson, D. C., & Spivey, M. J. (2000). Representation, space, and Hollywood Squares: Looking at things that aren?t there anymore. Cognition, 76, 269-295. Riener, C. R., Stefanucci, J. K., Proffit, D. R., & Clore, G. L. (2011). An efect of mood on geographical slant perception. Cognition & Emotion, 25, 174-182. Ruiz, R. A., & Krauss, H. H. (1968). Perceptual defense versus response suppresion. Journal of Psychology, 69, 33-37. Sales, B. D., & Haber, R. N. (1968). A diferent look at perceptual defense for taboo words. Perception & Psychophysics, 3, 156-160. Sherif, M. (1936). The psychology of social norms. New York: Harper. Singer, B. R. (1956). An experimental inquiry into the concept of perceptual defense. British Journal of Psychology, 47, 298-311. Solomon, R. L., & Postman, L. (1952). Frequency of usage as a determinant of recognition thresholds for words. Journal of Experimental Psychology, 43, 195-201. Spence, D. P. (1957). A new look at vigilance and defense. Journal of Abnormal and Social Psychology, 54, 103-108. Stein, K. B. (1953). Perceptual defense and perceptual sensitization under neutral and involved conditions. Journal of Personality, 21, 467-478. Szymanski, J., & O?Donohue, W. (1995). Fear of Spiders Questionnaire. Journal of Behavior Therapy and Experimental Psychiatry, 26, 31-34. 60 Thurstone, L. L. (1944). A factorial study of perception. Chicago: The University of Chicago Pres. Wiener, M., & Schiler, P. H. (1960). Subliminal perception or perception of partial cues. Journal of Abnormal and Social Psychology, 61, 124-137. Wit, J. K., Proffit, D. R., & Epstein, W. (2004). Perceiving distance: A role of efort and intent. Perception, 33, 577-590. Zajonc, R. B., & Nieuwenhuyse, B. (1964). Relationship betwen word frequency and recognition: Perceptual proces or response bias? Journal of Experimental Psychology, 67, 276-285. Zigler, E., & Yospe, L. (1960). Perceptual defense and the problem of response suppresion. Journal of Personality, 28, 220-239. 61 Figure 1. Mean perceptual judgment acuracy (+/- 1 SEM) for egocentric distance to the water bottle as a function of condition. -5 -4 -3 -2 -1 0 1 2 3 4 5 Per ceived ? Actual Distance (in.) Egocentric Distance Thirsty Quenched 62 Figure 2. Mean perceptual judgment acuracy (+/- 1 SEM) for water bottle height as a function of condition. -5 -4 -3 -2 -1 0 1 2 3 4 5 Per ceived ? Actual Height (in.) Height Thirsty Quenched 63 Figure 3. Mean perceptual judgment acuracy (+/- 1 SEM) for adjusted distance to the water bottle as a function of condition. -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 Per ceived ? Actual Distance (in.) Adjusted Distance Thirsty Quenched 64 Figure 4. The scater plot ilustrates participants? step-back response after thirst (or thirst satiation) was induced (as a percentage of their baseline) in relation to their perceptual judgment acuracy for egocentric distance. 0 25 50 75 100 125 150 175 200 -25 -20 -15 -10 -5 0 5 10 15 20 25 Perceived ? Actual Distance (in.) St e p - ba c k R e s pon s e ( % ) 65 Figure 5. Mean desirability ratings (+/- 1 SEM) as a function of group and object. Ratings are based on a Likert scale, ranging from 1 (Very Undesirable) to 7 (Very Desirable). 1 2 3 4 5 6 7 Spider-tolerant Spider-fearful Gift Card Business Card Apparent Feces Tarantula De s i r a b i l i t y Ra t i n g 66 Figure 6. Mean threat ratings (+/- 1 SEM) as a function of group and object. Ratings are based on a Likert scale, ranging from 1 (Not at Al) to 7 (Very Much So). 1 2 3 4 5 6 7 Spider-tolerant Spider-fearful Gift Card Business Card Apparent Feces Tarantula Thr e a t R a t i ng 67 Figure 7. Mean disgust ratings (+/- 1 SEM) as a function of group and object. Ratings are based on a Likert scale, ranging from 1 (Not at Al) to 7 (Very Much So). 1 2 3 4 5 6 7 Spider-tolerant Spider-fearful Gift Card Business Card Apparent Feces Tarantula Di s g u s t Ra t i ng 68 Figure 8. Mean perceptual judgment acuracy (+/- 1 SEM) for egocentric distance as a function of group and object. -10 -8 -6 -4 -2 0 2 4 6 8 10 Spider-tolerant Spider-fearful Gift Card Business Card Apparent Feces Tarantula Egocentric Distance Pe r c e i v e d ? Ac t u a l D i s t a n c e (i n .) 69 Figure 9. Mean perceptual judgment acuracy (+/- 1 SEM) for object length as a function of group and object. -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 3 Spider-tolerant Spider-fearful Gift Card Business Card Apparent Feces Tarantula Object Length Pe r c e i v e d ? Ac t u a l L e n g t h ( i n . ) 70 Figure 10. Mean perceptual judgment acuracy (+/- 1 SEM) for adjusted distance as a function of group and object. -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 Spider-tolerant Spider-fearful Gift Card Business Card Apparent Feces Tarantula Adjusted Distance Pe r c e i v e d ? Ac t u a l D i s t a n c e (i n .) 71 Figure 11. The scater plot ilustrates participants? perceptual judgment acuracy for egocentric distance to the contained tarantula in relation to their respective FSQ scores. -40 -30 -20 -10 0 10 20 30 40 0 10 20 30 40 50 60 70 80 90 100 110 120 FSQ Score Perceived - Actual Distance (in.) 72 Figure 12. The scater plot ilustrates participants? perceptual judgment acuracy for length of the contained tarantula in relation to their respective FSQ scores. -5 -4 -3 -2 -1 0 1 2 3 4 5 0 10 20 30 40 50 60 70 80 90 100 110 120 FSQ Score Perceived - Actual Length (in.) 73 Figure 13. The scater plot ilustrates participants? perceptual judgment acuracy for egocentric distance to the contained tarantula in relation to their respective SPQ scores. -40 -30 -20 -10 0 10 20 30 40 0 3 6 9 12 15 18 21 24 27 30 SPQ Score Perceived - Actual Distance (in.) 74 Figure 14. The scater plot ilustrates participants? perceptual judgment acuracy for length of the contained tarantula in relation to their respective SPQ scores. -5 -4 -3 -2 -1 0 1 2 3 4 5 0 3 6 9 12 15 18 21 24 27 30 SPQ Score Perceived - Actual Length (in.) 75 Figure 15. The scater plot ilustrates participants? perceptual judgment acuracy for egocentric distance to the contained tarantula in relation to their respective ratings of perceived threat on a 7-point Likert scale. -40 -30 -20 -10 0 10 20 30 40 1 2 3 4 5 6 7 Rating of Threat Perceived - Actual Distance (in.) 76 Figure 16. The scater plot ilustrates participants? perceptual judgment acuracy for length of the contained tarantula in relation to their respective ratings of perceived threat on a 7-point Likert scale. -5 -4 -3 -2 -1 0 1 2 3 4 5 1 2 3 4 5 6 7 Rating of Threat Perceived - Actual Length (in.) 77 Figure 17. The scater plot ilustrates participants? perceptual judgment acuracy for egocentric distance to the contained tarantula in relation to their respective ratings of perceived disgust on a 7-point Likert scale. -40 -30 -20 -10 0 10 20 30 40 1 2 3 4 5 6 7 Rating of Disgust Perceived - Actual Distance (in.) 78 Figure 18. The scater plot ilustrates participants? perceptual judgment acuracy for length of the contained tarantula in relation to their respective ratings of perceived disgust on a 7-point Likert scale. -5 -4 -3 -2 -1 0 1 2 3 4 5 1 2 3 4 5 6 7 Rating of Disgust Perceived - Actual Length (in.) 79 Figure 19. Mean step-back response (+/- 1 SEM) of spider-tolerant and spider-fearful individuals to each object as a percentage of their baseline. 40 60 80 100 120 140 Spider-tolerant Spider-fearful Gift Card Business Card Apparent Feces Tarantula St e p - ba c k R e s pon s e ( % ) 80 Figure 20. The scater plot ilustrates participants? step-back response to the contained tarantula (as a percentage of their baseline) in relation to their perceptual judgment acuracy for egocentric distance to the tarantula. 0 25 50 75 100 125 150 175 -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 Perceived ? Actual Distance (in.) St e p - ba c k R e s pon s e ( % ) 81 Figure 21. The scater plot ilustrates participants? step-back response to the contained tarantula (as a percentage of their baseline) in relation to their respective FSQ scores. 0 25 50 75 100 125 150 175 0 10 20 30 40 50 60 70 80 90 100 110 120 FSQ Score Step-back Response (%) 82 Figure 22. The scater plot ilustrates participants? step-back response to the contained tarantula (as a percentage of their baseline) in relation to their respective SPQ scores. 0 25 50 75 100 125 150 175 0 3 6 9 12 15 18 21 24 27 30 SPQ Score Step-back Response (%) 83 Figure 23. The scater plot ilustrates participants? step-back response to the contained tarantula (as a percentage of their baseline) in relation to their respective ratings of perceived threat on a 7- point Likert scale. 0 25 50 75 100 125 150 175 1 2 3 4 5 6 7 Rating of Threat Step-back Response (%) 84 Figure 24. The scater plot ilustrates participants? step-back response to the contained tarantula (as a percentage of their baseline) in relation to their respective ratings of perceived disgust on a 7-point Likert scale. 0 25 50 75 100 125 150 175 1 2 3 4 5 6 7 Rating of Disgust Step-back Response (%) 85 Figure 25. The scater plot ilustrates participants? step-back response to the busines card (as a percentage of their baseline) in relation to their respective perceptual judgment acuracy for egocentric distance to the busines card. 0 25 50 75 100 125 150 175 -40 -30 -20 -10 0 10 20 30 40 Perceived - Actual Distance (in.) St e p - ba c k R e s pon s e ( % ) 86 Figure 26. The scater plot ilustrates participants? step-back response to the gift card (as a percentage of their baseline) in relation to their respective perceptual judgment acuracy for egocentric distance to the gift card. 0 25 50 75 100 125 150 175 -40 -30 -20 -10 0 10 20 30 40 Perceived - Actual Distance (in.) St e p - ba c k R e s pon s e ( % ) 87 Figure 27. The scater plot ilustrates participants? step-back response to the apparent feces (as a percentage of their baseline) in relation to their respective perceptual judgment acuracy for egocentric distance to the apparent feces. 0 25 50 75 100 125 150 175 -40 -30 -20 -10 0 10 20 30 40 Perceived - Actual Distance (in.) St e p - ba c k R e s pon s e ( % ) 88 Figure 28. The scater plot ilustrates participants? step-back response to the contained tarantula (as a percentage of their baseline) in relation to their respective perceptual judgment acuracy for length of the contained tarantula. 0 25 50 75 100 125 150 175 -5 -4 -3 -2 -1 0 1 2 3 4 5 Perceived - Actual Length (in.) St e p - ba c k R e s pon s e ( % ) 89 Figure 29. The scater plot ilustrates participants? step-back response to the gift card (as a percentage of their baseline) in relation to their respective perceptual judgment acuracy for length of the gift card. 0 25 50 75 100 125 150 175 -5 -4 -3 -2 -1 0 1 2 3 4 5 Perceived - Actual Length (in.) St e p - ba c k R e s pon s e ( % ) 90 Figure 30. The scater plot ilustrates participants? step-back response to the busines card (as a percentage of their baseline) in relation to their respective perceptual judgment acuracy for length of the busines card. 0 25 50 75 100 125 150 175 -5 -4 -3 -2 -1 0 1 2 3 4 5 Perceived - Actual Length (in.) St e p - ba c k R e s pon s e ( % ) 91 Figure 31. The scater plot ilustrates participants? step-back response to the apparent feces (as a percentage of their baseline) in relation to their respective perceptual judgment acuracy for length of the apparent feces. 0 25 50 75 100 125 150 175 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 Perceived - Actual Length (in.) St e p - ba c k R e s pon s e ( % ) 92 Appendix A Spider Questionnaire (SPQ) Instructions: Answer each of the folowing statements either True or False as you feel they generally apply to you. If the statement is true most of the time or mostly true for you, you would answer true. If it is mostly false or false most of the time, mark it false. Indicate your answer by placing a mark (X) in the appropriate column. TRUE FALSE ______ ______ 1. I avoid going to parks or on camping trips because there may be spiders about. ______ ______ 2. I would fel some anxiety holding a toy spider in my hand. ______ ______ 3. If a picture of a spider crawling on a person apears on the screen during a motion picture, I turn me head away. ______ ______ 4. I dislike loking at pictures of spiders in a magazine. ______ ______ 5. If there is a spider on the ceiling over my bed, I canot go to slep unles someone kils it for me. ______ ______ 6. I enjoy watching spiders build webs. ______ ______ 7. I am terrified by the thought of touching a harmles spider. ______ ______ 8. If someone says that there are spiders anywhere about, I become alert and on edge. ______ ______ 9. I would not go down to the basement to get something if I thought there might be spiders down there. ______ ______ 10. I would fel uncomfortable if a spider crawled out of my shoe as I tok it out of the closet to put it on. ______ ______ 11. When I se a spider, I feel tense and restless. ______ ______ 12. I enjoy reading articles about spiders. ______ ______ 13. I fel sick when I se a spider. ______ ______ 14. Spiders are sometimes useful. ______ ______ 15. I shuder when I think of spiders. ______ ______ 16. I don?t mind being near a non-poisonous spider is there is someone there in whom I have confidence. ______ ______ 17. Some spiders are very atractive to lok at. ______ ______ 18. I don?t believe anyone could hold a spider without some fear. ______ ______ 19. The way spiders move is repulsive. ______ ______ 20. It wouldn?t bother me to touch a dead spider with a long stick. ______ ______ 21. If I came upon a spider while cleaning the atic I would probably run. ______ ______ 22. I?m more afraid of spiders than any other animal. ______ ______ 23. I would not want to travel to Mexico or Central America because of the greater prevalence of tarantulas. ______ ______ 24. I am cautious when I buy fruit because bananas may atract spiders. 93 ______ ______ 25. I have no fear of non-poisonous spiders. ______ ______ 26. I wouldn?t take a course in biology if I thought I might have to handle live spiders. ______ ______ 27. Spider webs are very artistic. ______ ______ 28. I think that I?m no more afraid of spiders that the average person. ______ ______ 29. I would prefer not to finish a story if something about spiders was introduced into the plot. ______ ______ 30. Even if I was late for a very important apointment, the thought of spiders would stop me from taking a shortcut through an underpas. ______ ______ 31. Not only am I afraid of spiders, but milipedes and caterpilars make me fel anxious. 94 Appendix B FSQ Instructions: Rate to what extent you now believe that the following statements are characteristic of your felings, thoughts, and behaviors towards spiders. 1. If I came across a spider now, I would get help from someone else to remove it. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 2. I sometimes now am on the look out for spiders. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 3. If I saw a spider now, I would think it wil harm me. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 4. I now think a lot about spiders. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 5. I would be somewhat afraid to enter a room now, where I have sen a spider before. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 6. I now would do anything to try to avoid a spider. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 95 7. I sometimes now think about geting bit by a spider. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 8. If I encountered a spider now, I wouldn't be able to deal efectively with it. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 9. If I encountered a spider now, it would take a long time to get it out of my mind. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 10. If I came across a spider now, I would leave the room. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 11. If I saw a spider now, I would think it wil try to jump on me. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 12. If I saw a spider now, I would ask someone else to kil it. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 13. If I encountered a spider now, I would have images of it trying to get me. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 96 14. If I saw a spider now I would be afraid of it. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 15. If I saw a spider now, I would fel very panicky. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 16. Spiders are one of my worst fears. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 17. I would fel very nervous if I saw a spider now. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree 18. If I saw a spider now I would probably break out in a sweat and my heart would beat faster. 1 2 3 4 5 6 7 Strongly Agree Strongly disagree agree