Visual field differences in an enumeration task of dots

Abstract

To investigate the functional hemispheric difference in visual information processing, a random dot pattern consisting of 1-9 dots was presented either centrally or peripherally to 16 right-handed male university students. Ss were asked to report the perceived number of dots as quickly as possible and to assign a confidence rating score to each report. Accuracy scores showed no significant visual field (VF) difference, though a left VF superiority had been reported by D. Kimura (1966). Reported numbers of dots were larger in the right than in the left VF. Examination of reaction times (RTs) as a function of the reported number of dots indicated that counting rates were similar in both VFs. However, inclusive RTs (including RTs for incorrect responses) as a function of the actual number of dots were longer in the right than left VF. These results, as well as confidence rating data, are explained by the left hemisphere superiority in the early stages of visual information processing of dots. (26 ref) (PsycINFO Database Record (c) 2002 APA, all rights reserved) Record 653 of 887 in PsycINFO 1985-1987