Facial expression is very important but little or nothing is known about how or where the brain mechanisms for controlling facial movements exist. It is known that certain drugs such as amphetamine produce among other effects, a stereotyped set of movements including facial movements. The PI has discovered that by injecting small amounts of amphetamine into a specific part of the brain she can produce pure facial movements. This discovery provides a new approach to defining the neurons which are involved in the movements, in terms of their neuroanatomy and the neurtransmitters which they use. It is an interesting new line of research which can gives us some precision in sorting out brain pathways related to behavior.