The primary aim of the present research project is to investigate the preliminary effects of four weeks of forehead temperature-regulating therapy on insomnia in adults with Tourette's disorder and co-occurring insomnia disorder. This project will also examine the effects of the device on depression, anxiety, and daytime sleepiness, and explore its effects on tic severity.

Tourette's disorder is a neurological condition marked by multiple motor tics and one or more vocal tics present for longer than one year, and neural dysfunction within the frontal region of the brain. Sleep disturbance, particularly insomnia, is common in Tourette's disorder. Existing treatments (medication, behavior therapy) for Tourette's disorder do not benefit everyone. The sleep-wake cycle, which may overlap with Tourette's disorder with respect to underlying brain-based deficits, provides a key target for tailored intervention. Forehead temperature-regulating therapy, designed to treat insomnia through targeting underlying brain-based functioning, provides one such intervention. Therefore, the aim of the present investigation is to examine the preliminary effects of forehead temperature-regulating therapy on 1) insomnia, 2) depression, anxiety and daytime sleepiness, and 3) tic severity in adults with Tourette's disorder and co-occurring insomnia disorder.

Participation involves an initial assessment, during which an evaluator will screen for psychiatric and sleep disorder diagnosis, tic severity, and cognitive functioning. Participants will rate sleep apnea risk, insomnia severity, depression, anxiety, and daytime sleepiness. Participants will then monitor sleep for seven consecutive nights by wearing a wrist actigraph (sleep watch) and completing a sleep diary. Participants will then complete a pre-treatment evaluation, during which an evaluator will reassess tic severity, and participants will rate depression, anxiety, and daytime sleepiness. After the pre-treatment evaluation, participants will use a forehead temperature-regulating therapy device nightly for four weeks. Participants will use the actigraph and sleep diary to monitor sleep continuously for the remainder of the study. Following the intervention, participants will complete a post-treatment assessment involving clinician-rated tic severity interview, and re-rating of depression, anxiety, and daytime sleepiness measures. Findings will help researchers determine the degree to which non-medication treatments are helpful for insomnia in people with Tourette's disorder.

Inclusion Criteria:

• DSM-5 diagnosis of Tourette's disorder
• DSM-5 diagnosis of Insomnia disorder
• Yale Global Tic Severity Scale Score ≥ 14 for Tourette's disorder or ≥ 10 for persistent motor tic disorder or persistent vocal tic disorder
• Insomnia Severity Index score > 14
• Sleep efficiency ≤ 85 per cent on 50 percent or greater nights over monitoring week, per Consensus Sleep Diary
• Age of 18 to 50 years
• English fluency

Exclusion Criteria:

• Current or lifetime diagnosis of bipolar disorder, psychosis, or pervasive developmental disorder
• Suicidality, severe depression or anxiety, or alcohol or substance dependence present within the past 6 months
• Moderate to severe sleep apnea risk per score of ≥ 3 on the Stop-Bang Questionnaire
• current diagnosis of Narcolepsy
• Wechsler Abbreviated Scale for Intelligence-Second Edition IQ score < 80
• Changes in prescribed or over-the-counter medications for sleep within prior month and planned during the study
• Changes in tic or other psychotropic medication within prior month and planned during study
• Caffeine use > 3 cups per day
• Behavior therapy for tics or sleep within prior 3 months
• Travel across > 2 time zones in prior month
• Shift work, or irregular sleep schedule (i.e., nightly variation of > 3 hours in bedtime or wake time, or time in bed duration < 5.5 or > 10 hours per night)
• Raynaud's disease or severe cold sensitivity
• Other major medical or neurological condition