Abstract

This chapter begins with historical accounts of the corpus callosum. It then discusses the results of the investigation of the CC of rhesus monkey brains. Fibers destined to traverse the CC and travel to the opposite hemisphere leave the cortex of any given cortical area as part of the dense cord of fibers lying in the central part of the white matter. Callosal fibers are sometimes identifiable as distinct from the subcortical bundle that forms the other major component of the cord, but more usually they are indistinguishable from them early in their course. As the cord fibers leave the white matter of the gyrus, they separate into two major components—the commissural fibers course medially to enter the CC, and the subcortical fibers take a course unique to each cortical area. Callosal fibers from the different parts of the cerebral cortex gather above and lateral to the lateral ventricle, enter the CC, and course medially in a compact bundle in a topographical manner to reach the opposite hemisphere.