Abstract
We reviewed, 1) the concept of the spatial cognition and the brain areas resposible to the spatial cognition from a human neuropsychological viewpoint, 2) the role of the hippocampus on the spatial cognition processing in animals and the two major hypotheses concerned to hippocampal function in various spatial cognition tasks : cognitive map hypothesis and working memory hypothesis, and 3) our recent studies which showed the spatial cognition impairment in the experimentally-induced microencephalic rats with abnormal morpho-and/or neuro-genesis of the hippocampus by prenatal methylazoxymethanol (MAM) injection. The spatial cognition impairment observed in our experiments was very similar to that observed in rats with surgical lesions of the hippocampus. Combined our behavioral results with brain histological examinations, it is considered that the spatial cognition impairment observed in prenatal MAM-treated rats was due more to the effects of MAM on the hippocampus than to its effects on the cerebral cortex. (Japanese Journal of Physiological Psychology and Psychophysiology, 21 (1) : 19-30, 2003.)
