At the Joes injury, the grey matter looks like a butterfly-shaped are. While the white matter has tracts which are either ascending or descending. For example, we have corticospinal which is ascending tract. Grey matter it is the thin cerebral cortex for each hemisphere of the cerebrum and it is composed of interneurons which integrate information.
White matter consists of myelinated axons that lie low below the cerebral cortex.
The two hemisphere connects together by the corpus callosum.