Tourette Syndrome (TS) is a common developmental disorder characterized by repetitive, involuntary movements and vocalizations called tics. Long seen as involving only the motor system, research has begun to highlight the involvement of sensory system dysfunction in TS as well. This notion is supported by both research and anecdotal evidence; people with TS often report a sensory urge (e.g., itchy throat) that contributes to the need to complete the tic (e.g., throat clearing), which provides temporary relief. It is thought that the persistent nature of these sensory urges may represent the brain’s difficulty with adapting to tactile (touch) sensory experiences. This means that the brain may have difficulty ignoring stimuli in the environment that most people acclimate to or don’t even notice. This ability to adapt has been found to be associated with inhibitory (GABA) neurotransmission in the brain. Preliminary data from our laboratory suggest that children with TS have abnormalities in tactile adaptation that is consistent with inhibitory (GABAergic) dysfunction.
TS has a significant impact on quality of life, yet the treatments remain moderately effective, at best, for many with this syndrome. A more thorough understanding of the pathophysiology of TS, from premonitory urge to the tic itself, would lead to more targeted and effective treatments. Addressing this, we are examining tactile sensitivity and adaption, brain GABA concentration, and GABA inhibitory function in the sensorimotor systems in children with and without TS. The comparison between these groups will contribute to improved understanding of sensorimotor dysregulation, and resulting tics as well as other symptoms (e.g., ADHD and obsessive-compulsive behavior), seen in TS. More>