DELAYS IN RECOGNIZING FACIAL EXPRESSIONS RESULTING FROM PROLONGED VIEWING OF ADAPTATION FACE STIMULI

The main purpose of the present study was to investigate the mechanism underlying fundamental dimensions in recognition of facial expression s, using the prolonged viewing method. Pictures of female faces were u sed, which displayed one of the following six: happiness, sadness, sur prise, anger, disgust, and neutral expressions. In Experiment 1, the m ean ratings of each expression on each picture were analyzed with prin cipal component analysis (PCA). In Experiment 2, subjects orally judge d the expressions of test faces following either one or 25 seconds of viewing of an adaptation face. Significant delays occurred in the prol onged viewing condition only when the adaptation face had a higher abs olute value on 'pleasantness,' the first component of PCA, than the te st face. In contrast, adaptation faces that were high only on 'arousal ,' the second component, produced no such effects. It was suggested th at there are at least two subsystems involved in the recognition of fa cial expressions and that each system has different temporal character istics.