Transcranial Magnetic Stimulation to Augment Behavior Therapy for Tics

Transcranial Magnetic Stimulation to Augment Behavior Therapy for Tics

The study will examine whether combining Comprehensive Behavioral Intervention for Tics (CBIT) with inhibition of the supplementary motor area (SMA) using transcranial magnetic stimulation (TMS) normalizes activity in the SMA-connected circuits, improves tic suppression ability, and enhances CBIT outcomes in young people with tic disorder. The study will also examine different TMS dosing strategies.

All participants will receive 10 daily sessions of CBIT, a well-established behavioral treatment that is considered by the American Academy of Neurology to be the first-line intervention for tics. Immediately prior to each CBIT session, participants will undergo TMS targeting the SMA. The specific type of TMS procedure will be randomly assigned between subjects and be either: 1 Hz repetitive TMS (rTMS), continuous theta burst stimulation (cTBS), or sham stimulation.

Inclusion Criteria:

• Current chronic motor and/or vocal tics, defined as tics for at least 1 year without a tic-free period of more than 3 consecutive months. Tics must not be due to a medical condition or the direct physiological effects of a substance.
• At least moderate tic severity, defined as a Yale Global Tic Severity Scale total score ≥14 (≥9 for those with motor or vocal tics only).
• Full scale IQ greater than or equal to 70
• English fluency to ensure comprehension of study measures and instructions.
• Right-handed

Exclusion Criteria:

• Medical conditions contraindicated or associated with altered TMS risk profile, including history of intracranial pathology, epilepsy or seizure disorders, traumatic brain injury, brain tumor, stroke, implanted medical devices or metallic objects in the head, current pregnancy or participants of childbearing age not using effective contraception, or any other medical condition deemed serious or contraindicated by a study physician
• Inability to undergo MRI.
• Left handedness.
• Active suicidality.
• Previous diagnosis of psychosis or cognitive disability.
• Substance abuse or dependence within the past year.
• Concurrent psychotherapy focused on tics.
• Neuroleptic/antipsychotic medications.
• Taking a medication that has not reached stability criterion (same medication and dose for 6 weeks with no planned changes over the intervention period)