Corpus collosum

The corpus callosum is the structure in the brain that joins the two hemispheres of the cerebellum and allows them to communicate with each other. This communication appears to allow humans to connect concepts with words and a damaged corpus callosum has the effect of not allowing patients to match up concepts they see in one eye with concepts in the other half of the brain.
In some cases, particularly to deal with severe seizures, the corpus callosum is surgically severed to prevent the two hemispheres from interacting. Scott had such surgery before the events in Both Sides Now.
Corpus callosum at Wikipedia
Category:Anatomy