Split-Brain Functioning

For centuries it had been suspected that the two hemispheres of the brain had specialized functions. Increased interest in certain divisions of function between the two brain hemispheres can be traced to the 1860s when Pierre Paul Broca (1824-1880), a French physician, reported that on autopsy a number of patients with speech impairments had lesions in the left frontal lobe of their brains. Systematic research on split-brain functioning, however, did not begin until the late 1960s, when Roger Sperry and his colleagues discovered certain regularly occurring differences in the functioning of the two brain hemispheres in split-brain patients (see below), and research has remained strong ever since that time.