Commissurotomy

Synonyms

Split brain

Definition

The term referring to the medical procedure in which interconnecting fibers between the cerebral hemispheres are lesioned. The anatomic location includes either or both anterior and posterior fibers. When posterior fibers are resected, connections to the hippocampus may also be affected.

Current Knowledge

The neurosurgical technique is based on the premise that when stimuli enters the brain it is rapidly communicated via the corpus callosum to the other hemisphere. In refractory epilepsy, severing the corpus callosum may prevent the spread of electrical activity between hemispheres and generalization of the seizure activity. This procedure prevents the communication of the two hemispheres thus resulting in a clinical scenario of a “split brain.” Clinical disconnection syndromes in these patients have been studied across a large number of neurocognitive tasks. These surgical lesions have allowed for the study of sensory perceptual processes and...