corpus callosum(redirected from commissure of cerebral hemispheres)
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corpus callosum:see brainbrain,
the supervisory center of the nervous system in all vertebrates. It also serves as the site of emotions, memory, self-awareness, and thought. Anatomy and Function
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in placental mammals and man, the aggregation of nerve fibers connecting the cerebral hemispheres.
The corpus callosum develops in the higher mammals from the commissure of the mantle (present in lung-fish, amphibians, reptiles, birds, and cloacal mammals) in connection with the strong development of the cerebral cortex. The fibers of the corpus callosum run mostly in a transverse direction, connecting and exchanging neural impulses between matching areas of the hemispheres. Therefore, both hemispheres together constitute a single unit. Fibers connecting different gyri in the two hemispheres also pass through the corpus callosum (for example, frontal with parietal or occipital). The fibers of the corpus callosum also send collaterals (associative fibers) to different parts of the same hemisphere.