What does the term "split brain" refer to?

The term "split brain" specifically refers to a surgical intervention known as a corpus callosotomy, which involves severing the corpus callosum, a band of nerve fibers that connects the two cerebral hemispheres. This procedure is typically performed to reduce the severity of severe epilepsy by limiting the spread of seizure activity between the two halves of the brain.

In a split-brain patient, each hemisphere can function independently, leading to distinct behaviors and capabilities. For example, the left hemisphere is generally associated with language processing, while the right hemisphere is often linked to visual-spatial abilities. This separation allows researchers to study the distinct functions of each hemisphere, which has provided significant insights into lateralization of brain functions.

The other options, while related to neurological issues, do not capture the specific meaning of "split brain." A stroke refers to an interruption of blood supply to the brain, a brain tumor is an abnormal growth that affects brain function, and a neurological disorder affecting coordination usually involves conditions such as ataxia, which do not entail the surgical separation of brain hemispheres. Hence, the definition of "split brain" accurately aligns with the surgical aspect of hemispheric isolation.