Abstract
Teenagers are generally more vulnerable to emotional distractions than adults, which may partly explain relatively poorer decision-making in this population. We have previously shown that performance on a flanker task is relatively mature by mid-adolescence for letter stimuli but not for emotional face stimuli. This follow-up study investigated how attention to a central affective face is modified by the presence of both affectively-opposite and affectively-neutral flanker stimuli in adolescents and adults. Since fMRI data suggest that repeated presentation of fearful faces results in neural habituation of the amygdala, changes in attentional capture by fearful faces over time were also investigated. Results showed that reaction time (RT) increased when the emotional expressions of flanker stimuli were incompatible with that of the target, for happy targets only. Identification of a central happy target was significantly slower when it was flanked by fearful faces than when flanked by happy faces, for both adults and adolescents. Furthermore, adolescents experienced significantly greater interference by fearful flankers than adults. In contrast, happy face flankers produced little change in RT for fearful targets for both adults and adolescents. Affectively-neutral flankers produced significantly increased RT for happy compared to fearful face targets in adults. This trend was not significant in adolescents, which may be due to difficulties in processing neutral faces. Adolescents experienced significantly more attentional capture by fearful faces in the first half of the experiment than adults, but their responses were adult-like by the second half of the experiment. Our data suggest that fearful faces capture attention more effectively than happy faces and adolescents are initially more vulnerable to this effect than adults. However, with repeated exposure this difference quickly diminishes. Increased sensitivity to fearful faces in adolescents is likely due to immature top-down processing that fails to adequately over-ride more bottom-up, affectively-driven processes.