Acta Psychologica Sinica


Vol. 37 No. 1 , Pages 14 - 18 , 2005

Task Difficulty in Perceptual Identification of Stimulus and Distributing Processing Across Two Hemispheres (Article written in Chinese)

CAI Houde

Abstract

Tachistoscopic visual half-field test was used to examine effects of an early perceptual factor of stimuli on the distributing processing across two hemispheres. An odd-even conceptual decision task on pairs of numerals in capitals of Chinese characters was given to subjects involving three different eccentricities (3.5, 5º and 6.5º) of comparative numerals in order to vary the perceptual processing demands of the stimuli. The results showed that the reaction times were slower and the percentage of errors higher while increasing eccentricity of the comparative stimuli. There was a superiority of correct reaction speed for RVF (LH) presentation, regardless of eccentricities and responding hands. A comparasion of the left and the right hand indicated that response with the left hand was more rapid than with the right hand at 6.5º, and response with the right hand was more rapid than with the left hand at 3.5º and 5º. These results suggest that the stimulus and response processing for this task tend to be distributed across the two hemispheres at 6.5º, and operated at 3.5º and 5º by the left hemisphere independently. The effect of distributing processing appeared at 6.5º could result from more difficult perceptual and attentional demands of the comparative stimuli.

Keywords: task difficulty; distributing processing; tachistoscopic visual half-field test; eccentricity

[Chinese Version | Index | Acta Psychologica Sinica | Other Journals | Subscription form | Enquiry ]


Mail any comments and suggestions to hkier-journal@cuhk.edu.hk .