<Tr> <Th> FMA </Th> <Td> 61817 </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terms of neuroanatomy (edit on Wikidata) </Td> </Tr> <P> The vertebrate cerebrum (brain) is formed by two cerebral hemispheres that are separated by a groove, the longitudinal fissure . The brain can thus be described as being divided into left and right cerebral hemispheres . Each of these hemispheres has an outer layer of grey matter, the cerebral cortex, that is supported by an inner layer of white matter . In eutherian (placental) mammals, the hemispheres are linked by the corpus callosum, a very large bundle of nerve fibers . Smaller commissures, including the anterior commissure, the posterior commissure and the fornix, also join the hemispheres and these are also present in other vertebrates . These commissures transfer information between the two hemispheres to coordinate localized functions . </P> <P> There are three known poles of the cerebral hemispheres: the occipital pole, the frontal pole, and the temporal pole . </P>

What connects the two sides of the brain