Anterior Cingulate Cognitive Processing in Tourette’s Disorder

Grant Type
Grant Year
Institution Location
Institution Organization Name
Washington University School of Medicine
Investigators Name
Pardo, Jose, MD, PhD

The anterior cingulate cortex is of particular interest for research on Tourette Syndrome (TS) for several reasons. This region of the brain, a part of the limbic system, is thought to be involved in higher level affective and motivational components of behavior. Direct electrical stimulation of the primate anterior cingulate results in species-specific utterances independent of the emotional state of the animal, potentially analogous to the vocalizations seen in patients with TS. Neurosurgical stimulation of the human anteriorcingulate cortex induces movements described by the patients as involuntary and difficult to resist — suggestive of the tics and compulsions seen in TS. The anterior cingulate cortex does not appear to be involved in lower-level motor processing such as sequential motor movements or imagined movements. Recent studies of normal humans indicate that at least a region of the anterior cingulate is involved in high-level processing selection, i.e., attention. Moreover, preliminary functional neuroimaging studies of patients with TS indicate hypometabolism of the anterior cingulate. Finally, the anterior cingulate cortex is known to be influenced by dopamine, a brain neurotransmitter which is known to play a major role in TS. We have found several simple reaction time tasks which require activation of the anterior cingu late cortex in normal human subjects as assessed by positron emission tomography (PET). These tasks are very sensitive probes of some regions of the anterior cingulate cortex, particularly those regions involved with attention. The studies funded by the Tourette Syndrome Association will apply these reaction time tasks to patients with TS to test the hypothesis that anterior cingu late processing may be dysfunctional in these patients, thereby providing additional evidence as to the regions of the brain disturbed in TS as well as insight into the brain operations affected. These investigations are an essential preamble to both PET functional neuroimaging and family studies of cognitive processing in TS. Jose V. Pardo, M.D., Ph.D. Washington University School of Medicine, St. Louis, MO Award $25,000 Tourette Association of America Inc. – Research Grant Award 1990