The corpus callosum (CC) is the major white matter tract connecting the right and left cerebral hemispheres of the brain. In Latin, corpus callosum means a big body which is appropriate given its large relative size in the brain.
The CC can be thought of as a a bridge between the 2 hemispheres or as the highway in the brain upon which information passes from one half of the brain to the other.
Today (Hellige, 1993)
· The corpus callosum allows information to be shared between the two hemispheres– this role is undisputed, how this process occurs is a matter of some debate.
· The role of the corpus callosum is based predominantly on excitatory effects.
· Processing that involves a particular region in one hemisphere serves to activate similar regions in the corresponding hemisphere.
· The role of the corpus callosum is based predominantly on inhibitory effects.
· Contradictory to the excitatory model, processing that involves a particular region in one hemisphere serves to suppress similar regions in the corresponding hemisphere.
· The corpus callosum acts as an ‘inhibitory barrier’ to block the passage of some types of information allowing each hemisphere to work autonomously.
· This hypothesis can explain cerebral laterlization and specialization.