A committee of psychiatrists, surgeons, ethicists, and others decided that the only course left for five people with otherwise untreatable mental disorders was to cut out a certain area of their brains. The region sits near the middle of the brain tucked between regions that have to do with thinking and emotion. It is known as the dorsal anterior cingulate cortex (ACC). In seldom-used surgery, the ACC is removed to relieve conditions such as major depression and obsessive-compulsive disorder, when every other treatment has failed. A research team lead by Emad Eskandar, an assistant professor of surgery at Harvard and director of functional neurosurgery at Massachusetts General Hospital (MGH), saw this as a rare opportunity to reach a new level of understanding about this complex and somewhat mysterious part of the brain. The five patients played computer video games that involved a monetary reward or loss during and after their surgeries. Upon analyzing the recordings, Eskandar and neurosurgeon Ziv Williams discovered that their brain cells showed the greatest activity when patients realized that there was a monetary loss. That response clearly indicated that this part of the brain is where a person becomes aware of a reward or loss. The group’s experiments were described in detail in the December 2004 issue of Nature Neuroscience.