Abstract
Purpose: Osada et al. (ARVO, 2000) demonstrated that low spatial frequency was more effective to judge the emotion of happy face than other emotional faces. We investigated the effect of global and local features of the face on the judgments of facial expressions using band-pass-filtered morphed photographs under the condition of first limited saccade eye movements. Method: We recorded the first saccades by the method of corneal reflection when subjects gave their first one for faces. The subject was required to look at one of fixation points that randomly presented at four corners. The face went out immediately at the moment the subject gave the first saccade to it. We showed upright or inverted morphed faces under the three conditions of spatial frequency range (4.65, 14.67, 34.63 cycles/face-width). 2AFC task was employed to judge the facial emotions, i.e. happy versus neutral, sad versus neutral, or disgusted versus neutral. Results: (1)The correct percentage dropped more significantly in the recognition of sad and disgusted faces than in the recognition of happy faces under the upright low passed condition. The low spatial frequency components were not effective in judging sad and disgusted faces even in the situation of limited saccades. (2) There were no prominent differences in the performance of judgements between three emotional faces under the upright condition at middle and high frequency ranges. Both middle and high spatial frequency components were available for discriminating between three kinds of emotional faces and neutral faces under the upright condition. (3)The performance abruptly dropped for the inverted version of three kinds of low passed filtered faces. It means that the inversion of the face breaks down the configuration of the face. (4)The performance decreased significantly under the inverted condition of high passed neutral faces. Subjects could not use the local features of the face by the limitation of first saccadic eye movements.
Supported by Grant #08451019 from the Ministry of Education, Japan.