In an article by Douglas Steinberg, titled "Can a Side of the Brain Determine Sick or Sane?", the old, but never researched idea that different sides of the brain can trigger different emotions is explored. Several years ago, a scientist named Alvaro Pascual-Leone asked subjects with medication-resistant depression to wear goggles which restricted either the left or right eye. His idea was that if depression were linked to one side of the brain, electrical signals sent from only one eye could help cure the perpetual sadness.
Pascual-Leone's idea actually wasn't his. In discussions with Fredric Schiffer, Schiffer had suggested that ordinary, taped-up goggles actually elicited mood changes in many depressed patients. Pascual-Leone had been skeptical, but when moments after putting on the goggles, some patients had "rather striking and well defined emotional responses," he was convinced. 20 patients felts 42% better when they wore Left Hemisphere activating goggles, and 15 felt 11% better with Right Hemisphere activating goggles. Pascual-Leone should have then tested to see how the people reacted to the goggles which stimulated the other hemisphere, but he didn't.
The theory behind this research is that because the axons of many retinal neurons cross the midline of the brain, the left brain receives a jolt when the right eye is stimulated, and vice versa. The Right Hemisphere is commonly associated with schizophrenia, and the Left Hemisphere with chronic depression. However, this data may be specific to the individual. So, scientists hypothesized, if electrical signals were focused on one side of the brain, the characteristics associated with the other side would be cured. However, Flor-Henry, an important scientist, makes it clear that, "A disturbance cannot be just in one hemisphere. The fundamental cause might originate in one hemisphere.".
Many scientists have tried to find the best way to cure depression and schizophrenia with this theory.