Abstract
We examined the respective capacities of the disconnected cerebral hemispheres of a commissurotomized subject to generate images of multipart objects. Two experiments were conducted, each comprising a perceptual and an imagery condition, in which the subject had to make a decision in response to segments of directly presented letters or to segments of imaged letters generated after presentation of their corresponding cases. In both experiments, the subject’s two hemispheres performed with high accuracy on perceived and generated letters, and with equal efficiency on the generated letters. This indicated that there was no hemispheric asymmetry in the subject’s creating and processing of images of multipart letters—a finding that is not consistent with results obtained with another “split-brain” patient. We therefore conclude that one should be cautious about basing theories of cerebral lateralization on data from this unusual neurological population.
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Preparation of this paper was supported by the Medical Research Council of Canada.
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Sergent, J., Corballis, M.C. Generation of multipart images in the disconnected cerebral hemispheres. Bull. Psychon. Soc. 28, 309–311 (1990). https://doi.org/10.3758/BF03334030
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DOI: https://doi.org/10.3758/BF03334030