Dual Brain Theory

In the 1960s, split-brain surgery was used to treat people suffering from severe epilepsy. These operations enabled scientists to investigate the properties of each separated hemisphere, the left and right brain. Patients who had their corpus callosum cut manifested two separate minds. Schiffer, a clinical instructor in psychiatry at HMS and McLean, believes that ordinary people also are of two minds, each associated with one hemisphere. Dual-brain therapy is his application of this principle toward helping people better understand and repair their psychological distresses. Inspired by research that suggested restricting vision to one side might allow a person to communicate preferentially with one hemisphere or the other, Schiffer devised glasses that allow vision only out of the left or right side. He found that about half his patients had a response to these "lateralizing" glasses, often feeling more anxious when looking to the right visual field (left brain) than to the left. Follow-up studies yielded similar results, suggesting that ordinary people frequently manifest two distinct personalities, each related either to the left or right hemisphere.