Split brain is the condition resulting from certain types of neurosurgery in which the connections between the two hemispheres of the brain are severed, so that the two cerebral hemispheres are no longer able to communicate with each other. This prevents the two hemispheres from processing information as a unified whole, leading to a dichotomous approach to perceptual and cognitive processes that can have a profound impact on psychological functioning and behaviour. While this condition can often lead to dramatic changes in the functioning of a person, some individuals have even been found to possess a considerable level of adaptability and plasticity, with each hemisphere developing attributes that enable it to compensate for the absence of the other.

See also: left hemisphere, right hemisphere, corpus callosum, divided brain