Individual patterns of visual exploration predict the extent of fear generalization in humans

Generalization of fear is considered an important mechanism contributing to the etiology and maintenance of anxiety disorders. Although previous studies have identified the importance of stimulus discrimination for fear generalization, it is still unclear to what degree overt attention to relevant stimulus features might mediate its magnitude. To test the prediction that visual preferences for distinguishing stimulus aspects are associated with reduced fear generalization, we developed a set of facial stimuli that was meticulously manipulated such that pairs of faces could either be distinguished by looking into the eyes or into the region around mouth and nose, respectively. These pairs were then employed as CS + and CS- in a differential fear conditioning paradigm followed by a generalization test with morphs in steps of 20%. Shock expectancy ratings indicated a moderately curved fear generalization gradient that is typical for healthy samples, but its shape was altered depending on individual attentional deployment: Particpants who dwelled on the distinguishing facial features faster and for longer periods of time exhibited less fear generalization. Although both pupil and heart rate responses also showed a generalization gradient, with pupil diameter and heart rate deceleration increasing as a function of threat, these responses were not significantly related to visual exploration. In total, the current results indicate that the extent of explicit fear generalization depends on individual patterns of attentional deployment. Future studies evaluating the efficacy of perceptual trainings that aim to augment stimulus discriminability in order to reduce (over)generalization seem desirable. (PsycInfo Database Record (c) 2023 APA, all rights reserved).