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Data & Analysis Threat Perception and Context Sensitivity Relation D. McDonald, S. Asi, and S. Lynn We created the graph using the results from each participant. The data collected is averaged to display the function of the participants' behavioral response to the target face series. The calculations were determined by calculating the participants’ average portion of times they said the target face was threatening. The graph displays the participants’ responses to the altered face (green) and the target face (blue). Introduction An individual’s ability to detect a threat could be altered by the context surrounding that target. The idea of “context sensitivity” has been studied as a key aspect to the decision making process. Context sensitivity argues that when there is a collection of options from which the decision maker must choose then the collection compromises a unique context (Busemeyer, 1993). In Busemeyer's study, he noticed this issue when studying economic decision making. Subjects were asked to choose between a gamble and a certain value. Using the simple scalability hypothesis the probability of each figure was supposed to decrease with the options. However, Busemeyer knew differently because the inconsistencies were due to the pairings of two choices, and the context affected the decision making process. Option A was "win or lose 5 cents with equal probability, B is the gamble "win or lose 50 cents with equal probability, C is a certain loss of 1 cent, and D is a certain gain of 1 cent. The probabilities of choosing A over C, B over C, A over D, and B over D were found. It was found that the probability was higher to choose A over C then B over C. These results would imply that the probability to pick A is greater than B. However, this was not the case, when the pairing was A over D, which meant that the participants made the decision based on the pairings rather than the We created an aged target face for the target face series to see if an aged version would stimulate a different response. Initially, we thought the aged face would be seen as less threatening due to its age (50-60 years old), but the aged face was perceived as more threatening in comparison to the targeted face. The graph represents the participants’ responses when stimulated with the target face (red) and the aged face (green). References Busemeyer, Jerome R., and James T. Townsend. "Decision Field Theory: A Dynamic-cognitive Approach to Decision Making in an Uncertain Environment." Psychological Review 100.3 (1993): 432-59. Web. 1 Dec. 2015. Olivola, C. Y., Funk, F., & Todorov, A. (2014). Social attributions from faces bias human choices. Trends in Cognitive Sciences, 18(11), 566-570. By comparing both graphs side by side, we were able to conclude that the threat perception of the target face was context sensitive, which makes the stimulus dependent on the other stimuli surrounding the targeted face. The graph’s inflection point is the participants’ threshold of behavioral responses to the targeted stimulus. The threshold determines where the participant’s perception of the faces shifts from non-threatening to threatening. When comparing the two data sets, the target face’s threshold shifted during Run 2, so participants found the target face to be less threatening when paired with the aged face than when paired with the young altered face in Run 1. Methods Our study examines the participant’s ability to effectively categorize two different faces during a threat perception task. We recruited 28 participants from the Northeastern University student body population. Participants saw two different series of faces that ranged from non-threatening physiognomy (i.e., shape facial features) to threatening physiognomy. According to previous research certain facial features create a more threatening look than others, for example, a stronger jaw line is more threatening than a rounded or weaker one (Olivola, 2014). Faces were constructed using FaceGen Modeler software. Each face series comprised 11 “morphs” of a “base” face. With each morph facial features would change very slightly, to almost unnoticeable distinctions. For example, the size of the individual’s nostrils went from very small to very large. The faces ranged from 1-11, one being the most non- threatening and 11 being most threatening. In run one of the experiment there the series were created from two young base faces. In run two of the experiment an old base face was used in place of one of the young base faces. The two young faces were approximately 20-30 years of age while the old face was approximately 50-60 years of age. During the perception Conclusion & Discussion The threat physiognomy’s dependency on a stimulus’ surroundings upholds Busemyer’s (1993) findings of context sensitivity because the choices surrounding each stimuli influence the participant’s perception and ultimately his or her decision. While conducting the threat physiognomy study, a person’s threat perception was affected by the options given. Threat perception experiences this phenomenon because an individual is affected by context sensitivity when analyzing a threat, making Busemyer’s (1993) findings applicable. Though successful in identifying context sensitivity, our experiment is limited by the demographics of the participants (solely Northeastern Students with an average age of 18-22 years) and the type of stimuli (only white males). Future studies would ideally study faces of both genders and different races, and the studies should select a larger variety for the demographic of participants. Currently, we are investigating how adding an additional stimulus to the face perception task would intensify or hinder a person’s threat perception. Context sensitivity is applicable to a person’s threat perception and would need further investigation to determine if the relation can be applied to all settings. Abstract Social threat perception is the ability to effectively identify person as a threat or not. We investigated whether or not people’s evaluation of a face as threatening is biased by other faces they are also evaluating. Participants had to judge two faces that were similar in features and state “yes” or “no” when asked if it is threatening. Participants earned and lost points for correct and incorrect categorization of the faces, and were instructed to earn as many points as they could. With the points as motivation, a slight bias to categorize faces as “not threatening” would maximize earnings. We hypothesized that the participants would not judge the target face, which was present in both experiments, any differently if it was paired with another face. However, according to the results context sensitivity, meaning people use everything in the situation to form judgments, altered how people perceived the target face, which is also called face two. Participants judged the target face to be more threatening when it was paired with a young face than when paired with an old face. These results show that the participants were judging the two faces in relation to each other rather than separately, as in the idea of context sensitivity. 1 2 3 4 5 6 7 8 9 10 11 0.00 0.20 0.40 0.60 0.80 1.00 1.20 Run 1 and Run 2 Results Mean Target Face, Run 1 Mean Target Face, Run 2 Range of faces from non-threatening to threatening Probability of perceived Threat 1 2 3 4 5 6 7 8 9 10 11 0.00 0.20 0.40 0.60 0.80 1.00 1.20 Run 1 Target Face, Run1 Altered Face, Run 1 Range of faces from non-threatening to threatening Probability of perceived Threat 1 2 3 4 5 6 7 8 9 10 11 0.00 0.20 0.40 0.60 0.80 1.00 1.20 Run 2 Target Face, Run2 Aged Target Face, Run2 Range of faces from non-threatening to threatening Probability of Perceived threat
