Cognitive control processes in behavior therapy for youth with Tourette's disorder.

BACKGROUND: Cognitive control processes are implicated in the behavioral treatment of Tourette's disorder (TD). However, the influence of these processes on treatment outcomes has received minimal attention. This study examined whether cognitive control processes and/or tic suppression predicted reductions in tic severity and treatment response to behavior therapy. METHOD: Fifty-three youth with TD or a pervasive tic disorder participated in a randomized wait list-controlled trial of behavior therapy. Following a baseline assessment to evaluate psychiatric diagnoses, tic severity, and cognitive control processes (e.g., response selection, inhibition, and suppression), youth were randomly assigned to receive eight sessions of behavior therapy (n = 23) or a wait list of equal duration (n = 28). Youth receiving immediate treatment completed a post-treatment assessment to determine improvement in tic severity. Meanwhile, youth in the wait list condition completed another assessment to re-evaluate tic severity and cognitive control processes, and subsequently received 8 sessions of behavior therapy followed by a post-treatment assessment to determine improvement. RESULTS: A multiple linear regression model found that pretreatment inhibition/switching on the Delis-Kaplan Executive Function System Color-Word Interference Test predicted reductions in tic severity after behavior therapy (ß = -.36, t = -2.35, p = .025, ƞ2 = .15). However, other cognitive control processes and tic suppression did not predict treatment response and/or reductions in tic severity. Small nonsignificant effects were observed in cognitive control processes after behavior therapy. CONCLUSION: Cognitive control processes may influence tic severity reductions in behavior therapy. Notably, even when other cognitive control processes are impaired and youth are initially unable to voluntarily suppress their tics, youth with TD can still benefit from behavior therapy. Findings offer implications for clinical practice and research for TD.

Sleep and chronotype in adults with persistent tic disorders.

OBJECTIVE: This study examined sleep disorders and sleep medication use rates, nighttime tics, and sleep and chronotype in relation to tic and co-occurring symptoms in adults with persistent tic disorders (PTDs), including Tourette's disorder (TD). METHODS: One hundred twenty-five adult internet survey respondents rated sleep history, sleep, chronotype, tic severity, impairment, attention deficit hyperactivity disorder, obsessive-compulsive symptoms, anxiety, depression, and emotional and behavioral dyscontrol. RESULTS: Bruxism, insomnia, tic-related difficulty falling asleep, and melatonin use were commonly endorsed. Sleep disturbance correlated with impairment, obsessive-compulsive symptoms, and emotional and behavioral dyscontrol. Eveningness correlated with vocal and total tic severity only in TD. Controlling for age and sex, age, impairment, and obsessive-compulsive symptoms predicted sleep disturbance, and age and tic severity predicted chronotype. CONCLUSIONS: Impairment and obsessive-compulsive symptoms play a role in sleep disturbance in adults with PTDs, and may be intervention targets. Eveningness relates to tic severity, which may suggest the utility of interventions to advance chronotype.

Morning light therapy in adults with Tourette's disorder.

BACKGROUND: Sleep disturbance is common among individuals with Tourette's Disorder (TD). Given that sleep is influenced by the circadian system, this study examined circadian rhythms and sleep in adults with TD, and explored the possible benefit of short-wavelength wearable morning light therapy. METHODS: Participants were 34 adults with TD (n = 14) and age- and sex-matched healthy controls (HC; n = 20). Participants were screened using clinician-rated diagnostic and tic severity interviews, and procedures lasted 3 consecutive weeks. Participants completed a baseline week of actigraphy. Adults with TD completed 2 weeks of Re-Timer™ morning light therapy and continued actigraphy monitoring. Dim light melatonin-onset (DLMO) phase assessment, tic severity interview, and measures of chronotype, sleep disturbance, daytime sleepiness, disability, depression, anxiety, and stress were completed at baseline and post-intervention. RESULTS: Adults with TD reported significantly greater eveningness and sleep disturbance relative to controls. Per wrist actigraphy, adults with TD exhibited significantly longer sleep-onset latency, lower sleep efficiency, and greater sleep fragmentation than HC. Following morning light therapy, there was a significant advance in DLMO phase, but not self-report or actigraphy sleep variables. There were small, statistically significant decreases in tic severity and impairment. There were also significant reductions in daytime sleepiness, and self-reported anxiety, but not depression, stress, or disability. Participants reported minimal side effects and rated light therapy as acceptable and comfortable. CONCLUSIONS: Findings showed some benefits following brief light therapy in TD; further exploration of the impact of spectral tuning the photic environment as part of treatment for TD subjects is warranted.