Processing of form stimuli presented unilaterally in humans, chimpanzees (Pan troglodytes), and monkeys (Macaca mulatta).
Visual forms were unilaterally presented using a video-task paradigm to 10 humans, 3 chimpanzees, and 2 rhesus monkeys to determine whether hemispheric advantages existed in the processing of these stimuli. Both accuracy and reaction time served as dependent measures. For the chimpanzees, a significant right hemisphere advantage was found within the first 3 test sessions. The humans and monkeys failed to show a hemispheric advantage as determined by accuracy scores. Analysis of reaction time data revealed a significant left hemisphere advantage for the monkeys. A Visual Half-Field x Block interaction was found for the chimpanzees, with a significant left visual field advantage in Block 2, whereas a right visual field advantage was found in Block 4. In the human subjects, a left visual field advantage was found in Block 3 when they used their right hands to respond. The results are discussed in relation to recent reports of hemispheric advantages for nonhuman primates.
Language Research Center, Department of Psychology, Georgia State University, Atlanta 30303.
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WD
Hopkins
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Washburn
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Rumbaugh
D000328:Adult; D000818:Animals; D004292:Dominance, Cerebral; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008253:Macaca mulatta / Q000523:psychology*; D008297:Male; D002679:Pan troglodytes / Q000523:psychology*; D010364:Pattern Recognition, Visual; D011597:Psychomotor Performance; D011930:Reaction Time; D013045:Species Specificity