Final answer:
The 'split-brain' surgery involved dividing the corpus callosum, the structure that connects the two hemispheres of the brain. This procedure was primarily performed to treat severe epilepsy, inhibiting seizure spread from one hemisphere to another.
Step-by-step explanation:
In the mid-20th century, neurosurgeons performed an operation known as the corpus callosotomy, more casually known as 'split-brain' surgery.
The structure that was split in these surgeries is the corpus callosum, a bundle of neural fibers connecting the left and right hemispheres of the brain. This was done primarily to treat patients suffering from severe epilepsy when other treatment options were ineffective.
The split was performed to prevent the rapid spread of seizure activity from one hemisphere to the other, therefore reducing the severity and frequency of seizures. Although this treatment comes with significant side effects, including the inability of the two hemispheres to communicate directly, it had positive effects on the reduction of epilepsy symptoms.
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