What term describes the surgical condition that involves severing the brain's two hemispheres?

The term that describes the surgical condition involving the severing of the brain's two hemispheres is "split brain." This procedure, known as a corpus callosotomy, is performed primarily to alleviate severe epilepsy that does not respond to other treatments. By cutting the corpus callosum, which is the band of nerve fibers connecting the two hemispheres, the communication between the left and right sides of the brain is disrupted. This surgical intervention can help control the spread of epileptic seizures from one hemisphere to another.

In individuals who have undergone this procedure, researchers have observed interesting and sometimes surprising effects on behavior and cognition, shedding light on the lateralization of brain functions. The left hemisphere is often associated with language, while the right is linked to spatial abilities and holistic processing. The distinct functionalities of each hemisphere become more pronounced following the surgery, leading to fascinating studies in behavioral neuroscience.

The other terms listed refer to different concepts. "Double-brain" is not a recognized term in neuroscience; "dual hemisphere" is not commonly used to describe this surgical condition; and "brain lateralization" refers to the specialization of certain functions in one hemisphere over the other, but it does not specifically imply the surgical alteration of their connectivity.