Clinical Research Directory

Investigating Changes in Premonitory Urges During Habit Reversal Training for Tics

The primary aim of this study is to learn more about premonitory urges (PU) when using Habit Reversal Training (HRT) to treat tics. The main focus of this study is to investigate if and when PU change during tic treatment sessions and between tic treatment sessions. Participants will: * Attend 5 study visits (approximately 1 to 1.5 hours each) for an intake, habit reversal training for 3 separate tics, and a post assessment * Attend 5 practice sessions (approximately 30 minutes each) over a week for 3 weeks (total 15 practice sessions) * Study visits and practice sessions will take place in person and online via secure videoconference

Serotonin Control of Impulsivity in Tourette Disorder

Tourette disorder (TD) is a neurodevelopmental disorder characterized by motor and vocal tics. It is often associated with multiple psychiatric comorbidities involving a high degree of impulsivity such as obsessive-compulsive disorders (OCD), attention-deficit hyperactivity disorders (ADHD), and intermittent explosive disorders (IED). Although a substantial body of clinical studies have emphasized the role of the dopamine system in motor symptoms, little is known about how the serotonergic (5-HT) system modulate both cognitive and affective abilities in TD. Several lines of evidence suggest that different 5-HT receptor subtypes may constitute a crucial factor in the development and maintenance of different symptoms. Because abnormal 5-HT2A receptor bindings have been reported in patients with TD and aripiprazole (drug of first choice) is a 5-HT2A antagonist, we hypothesize that 5-HT2A receptors may play an important role in regulating psychiatric symptoms in TD such as those characterized by impulsive behaviors. To investigate the involvement of 5-HT2A receptors in TD, we propose to perform a multimodal imaging study with 20 adult patients (ON and OFF treatment). Neuroimaging data will be collected with a hybrid system that simultaneously combines the positron emission tomography (PET) and the functional magnetic resonance imaging (fMRI). A highly selective PET radiotracer (\[18F\]-altanserin) will map 5-HT2A receptor bindings in the whole brain, while fMRI will provide detail information regarding the altered brain activities.