The Neurophysiology of action release in the Primate Model of Tourette Syndrome (2nd year)

Grant Type
Grant Year
Institution Location
Institution Organization Name
Bar-Ilan University Israel
Investigators Name
Bar-Gad, Izhar, PhD

Tourette Syndrome (TS) has been associated with the malfunction of a group of sub-cortical nuclei, the basal ganglia. The proposed study seeks to expand the scope of a project previously funded by the TSA which focused on exposing the role of the basal ganglia in tic formation. The results of this project are currently in press in the journal “Brain” and indicate that the output of the basal ganglia encodes the fine temporal structure of the tic (timing of the muscle contraction) but maintains a distributed coarse encoding of the spatial properties of the tic (muscle group of the contraction). In the current project we will expand the study to different brain areas which form the input and output of the basal ganglia, i.e. the cortex and thalamus. The goal of the project is to unravel the mechanism of the transformation between the tonic changes in the state of the animal and the phasic focused expression of the tics and its interaction with normal movement. This goal will be pursued using simultaneous multi-electrode extracellular recording in multiple brain structures in the behaving primate revealing the transformation in the encoded information along the cortico-basal ganglia pathway. Recording in the upstream inputs and the downstream targets in conjunction with the basal ganglia activity itself will shed light on the spatial (the “where” signal) and temporal (the “when” signal) properties of the release of undesired movements, the tics. Exposing the underlying neurophysiological mechanism of action release presenting as tic formation will lead to advances in our conceptual approach to Tourette Syndrome and may enable the development of novel therapeutic measures for the disorder. Izhar Bar-Gad, Ph.D. Bar-Ilan University, Ramat-Gan, Israel Award: $75,000 (2nd Year) Commentary: The changes in the brain that lead to the generation of tics and other features of TS remain unclear. Scientists believe that alterations in certain parts of the brain that control movements, together called the basal ganglia, play a role in causing the symptoms that are seen in people with the disorder. In this study, Dr. Bar-Gad will examine the brain in much detail to determine how the basal ganglia normally works and what changes occur in TS. To do this, he will measure the electrical activity in the brain of laboratory animals. These readings will be collected and interpreted to give a picture of how the brain functions during movements. These studies may shed light on how changes in the brain lead to the symptoms of TS. Tourette Association of America Inc. – Research Grant Award 2009-2010