Whereas phrenology was discredited, the idea of localization firmed in the minds of brain scientists. In the 1950s Canadian neurosurgeon Wilder Penfield created brain maps to assist his surgeries. Penfield treated patients with severe epilepsy by destroying the brain cells where the seizures supposedly originated. To prepare for the treatment, Penfield created maps by stimulating the brain with electrical probes to observed responses, and so more accurately target the responsible brain areas, thus hoping to reduce side effects from the destructive surgery.
In 1952, Penfield wrote that stimulating the temporal lobe led to vivid memory recall. This tidbit was oversimplified in pop psychology publications under Freudian sway, including the 1969 best-selling bunkum I’m OK, You’re OK, by American psychiatrist Thomas Harris. The book falsely claimed that the brain records memories in perfect detail but such exactness is not available to the conscious mind.
Penfield found a topological relationship of brain to body. This idea was furthered by discovery that the frontal lobes seemingly housed the brain’s motor processor, initiating and coordinating muscle movement. The 3 lobes behind the frontal lobe – temporal, parietal, and occipital – comprise the brain’s sensory system: active while processing sensory information from the eyes, ears, skin, and other organs.
In his brain mapping Penfield also hoped to a scientific basis for the existence of the human soul. Instead, his work only led other neurobiologists astray. Penfield did not find the soul embedded in neurons.
Because scientists believed that the brain had a fixed structure, and processing was localized, they assumed, and were taught, that the maps were immutable, and universal: the same brain map applied to every human. Very tidy but quite untrue.