http://goo.gl/uTHQaM
Led by Amelia Draper, the study found that higher levels of the neurochemical GABA in an area of the brain called the supplementary motor area (SMA) helped to reduce hyperactivity in the cortical areas of the brain responsible for movement.
People with Tourette syndrome have too many signals being sent to these cortical areas, leading to unwanted and occasionally inappropriate movements or sounds known as tics that the person may have little or no control over.
By reducing the hyperactivity in areas such as the SMA and the primary motor cortex (M1), only the strongest signals can be processed and produce movement.