With additional support from Florida International University and The Children s Trust.

The Society for Clinical Child and Adolescent Psychology (SCCAP): Initiative for Dissemination of Evidence-based Treatments for Childhood and Adolescent Mental Health Problems With additional support from Florida International University and The Children s Trust.

Keynote Evidence-based Treatment of Tourette s Syndrome and Tic Disorders Douglas Woods, PhD Professor of Psychology Associate Dean of Social Sciences, Education and Business The Graduate School University of Wisconsin-Milwaukee Milwaukee

Behavior Therapy for Children with Tourette Syndrome Douglas Woods, PhD Professor of Psychology Associate Dean of the Graduate School University of Wisconsin-Milwaukee 3

Disclosures-Woods Research Support NIMH Tourette s Syndrome Association Speaking honoraria From various academic institutions Tourette Syndrome Association Royalties Guilford Publications Context Press Oxford University Press Springer Press 4

What is a Tic? a sudden, rapid, recurrent, nonrhythmic, stereotyped motor movement or vocalization 5

Tics: Phenomenology Tics are neurologically based, not learned Tics involuntary, though may be suppressed Often comes with a premonitory sensation that is reduced temporarily after doing a tic From simple to complex tics (examples) Simple motor: eye blinking, shoulder shrugging Simple vocal: throat clearing, grunting Complex motor: touching, squatting, jumping Complex vocal: words and phrases 6

What is Tourette Syndrome? Motor and Vocal tics For 1 year + Impairment 7

Common Problems in Persons with TS Disorders Obsessive compulsive disorder ADHD Anxiety Depression Disruptive behavioral disorders Difficulties Anxiety Mood Impulse and behavior control Problems with learning 8

Course of Tourette Syndrome Starts in young children More common in males Starts with motor tics, then vocal Starts in the head and face, then in the body Starts with simple tics, then more complex tics Peak severity is in early to mid teens Symptoms wax and wane throughout disorder Development of comorbid conditions is usually later except for ADHD Typically treated with medication Symptoms are heavily and predictably influenced by surroundings 9

Behavioral Model of Tics Environment External & Internal Traditional domain of behavioral psych Brain/Physiology Tics

Why Look for Environment-Tic Relationships? By understanding how environmental (internal and external) antecedents and consequences impacts tics, the environment can be modified in a targeted way to promote tic reduction

Environment-Tic Relationships that Maintain Tics Antecedents Consequences Places/Situations Other People Activities Internal Experiences Tics Positive Reinforcement (e.g., others reactions to tics) Negative Reinforcement (e.g., escape from activities, relief from aversive unpleasant internal experiences

Antecedent Events that Impact Tics Being upset or anxious (Silva et al., 1995) Watching TV (Silva et al., 1995) Being Alone (Silva et al., 1995) Social Gatherings (Silva et al., 1995) Stressful Life Events (Surwillo et al., 1978) Hearing Others Cough (Commander et al., 1991) Talking about tics (Woods et al., 2001)

Consequence Events That May Impact Tics Tics can be made more frequent by Social reactions (e.g., Watson & Sterling, 1998) Parental attention or comfort Peer attention Escape from an aversive situation Reduction of premonitory urge as a result of a tic Tics can be made less frequent by Reinforcing suppression of tics Potential reinforcers for suppression could include Avoidance of teasing Being able to participate in a social activity or sport Avoidance of embarrassment

Negative Reinforcement Hypothesis of Tic Maintenance Premonitory Urge Tic Relief Negative Reinforcement Tics can be maintained by elimination of premonitory urge. Biological processes underlying the urge and it s reduction are not understood. 15

Experimental Studies Investigating the Effects of Consequences on Tics Study 1: Can reinforcing tic suppression create tic reduction? Study 2: Is it reinforcement that creates the reduction? Study 3: Can stimulus control over tics develop? Study 4: What effect does stress have on tics Study 5: Evidence for negative reinforcement hypothesis?

Analysis of Environmental Variables Controlling Tic Reduction Tic Detector Remote controlled operant token dispenser Inactive computer camera mounted on top of box Tokens delivered by experimenter who observes from behind an observation mirror Tokens delivered for every 10 sec. tic-free intervals Interval resets if a tic occurs Tokens later exchanged for small amount of money

Frequency (Tics) Percentage of Intervals (Tics) Study 1: Can reinforcing tic suppression create tic reduction? 4 children with TS Instructions to suppress produced a 10.3% reduction Adding reinforcement to instructions produced a 76% reduction Results suggest that consequences to tics can impact tic frequency Is it really the consequence, though, or just being reminded to suppress? Woods & Himle (2004). Journal of Applied Behavior Analysis 100 90 80 70 60 50 40 30 20 10 0 20 18 16 14 12 10 8 6 4 2 0 BL (Baseline) BL VI DRO VI DRO VI (Verbal Instructions) DRO (Reinforcement for No Tics) Billy Louis Nick Mary

Study 2: Is it the reinforcement? Alternating treatments design comparing 3 conditions Reinforced suppression Suppression + noncontingent reward No suppress (baseline) Each condition was 5 minutes Each condition occurred 3 times Order of conditions was presented randomly Four children participated Study suggested the contingent delivery of reward was important in successful suppression Himle & Woods (2007). Journal of Applied Behavior Analysis

Tic Frequency Subject 1 25 20 15 10 5 0 Contingent Non-Cont BL

Tic Frequency Subject 2 20 15 10 5 0 Contingent Non-Cont BL

Tic Frequency Subject 3 30 25 20 15 10 5 0 Contingent Non-Cont BL

Tic Frequency Subject 4 18 16 14 12 10 8 6 4 2 0 Contingent Non-Cont BL

Study 3: Can the environment develop stimulus control over tics? 10 children with TS/CTDs 4 Training sessions, consisting of 2 conditions Purple light (reinforced suppression) No light (baseline, no suppression) Each 5-min condition replicated 3 times in each training session 5 th session was a test of stimulus control No instructions given Light/no light condition presented three times No reinforcers delivered Behaviour Research and Therapy. Woods et al. (2009).

Stimulus Control-Means Across Conditions

Stimulus Control-Means Across Conditions Purple < BL, p<.01 Purple < BL, p<.01

Study 4: Effects of Stress on Tics 10 children with TS/CTD participated Mean age of 12.5 (9-17 years) Mean YGTSS = 24 Repeated Measures Design No suppression/no Stress (BASELINE) Reinforced Suppression (SUP) Stress/No Suppression (STRESS)-doing an age appropriate timed math test verbally Suppression + Stress (SUP+STRESS) Each condition was 5 minutes, each replicated twice Tics were counted and premonitory urge experience rated on a 0-8 scale Conelea et al. (in press). Behaviour Research and Therapy 27

SUP<BL, p<.05 BL=Stress SUP+STRESS > SUP, p<.05 Stress ratings higher in stress induction conditions 28

Effects of Stress on Tics Suggested stress alone may not have had a negative effect, but does so through a disrupted ability to suppress tics Failed to replicate premonitory urge effects on suppression (may have been methodological) Clinically, suggests that stress coping in conjunction with HRT may be helpful 29

Study 5: Evidence for Negative Reinforcement Hypothesis 5 children with TS participated Children ranged in age from 8 to 17 ABAB Withdrawal Design No suppression ( A phase)- occurred twice Reinforced Suppression ( B phase)- occurred twice Each condition was 5 minutes Tics were counted and premonitory urge experience rated on a 0-8 scale If the removal of the urge reinforces tics, then when tics are stopped, the urge should go up. When tics are allowed to occur, the urge should go down. Himle, Woods et al. (2007). Behaviour Research and Therapy.

Tics/Min Average Urge Rating 17 Year Old Male 12 10 8 6 4 2 8 7 6 5 4 3 2 1 Tics/Min URGE 0 BL DRO BL DRO BL 0

Tics/Min Average Urge Rating 14 Year Old Male 6 5 4 3 2 1 8 7 6 5 4 3 2 1 Tics/Min URGE 0 BL DRO BL DRO BL 0

Tics/Min Average Urge Rating 13 Year Old Male 70 60 50 8 7 6 40 30 5 4 3 #TICS URGE 20 2 10 1 0 BL DRO BL DRO BL 0

Tics/Min Average Urge Rating 10 Year Old Female 4 8 7 3 6 2 1 5 4 3 2 1 Tics/Min URGE 0 BL DRO BL DRO BL 0

Tics/Min Average Urge Rating 8 Year Old Female 4 8 7 3 6 2 1 5 4 3 2 1 Tics/Min URGE 0 BL DRO BL DRO BL 0

Evidence for the Negative Reinforcement Hypothesis Hypothesis is supported for some children with TS Negative reinforcement seems to play a larger role as child becomes older

Behavioral Treatments are Based on the Following General Principles The person s internal and external environment can impact TS symptoms The effects of these factors are unique to the individual To develop a useful treatment both the external and internal contingencies must be addressed 37

Managing External Environment Managed by functional assessment/intervention Example: Billy comes home from school stressed out and anxious. He goes to the den where his sister is watching TV and begins ticcing loudly. Billy s Sister gets upset and teases Billy. Billy s mom enters the room, sends his sister out of the room, comforts Billy, and lets him watch TV while he gets himself together. Now Billy tics a lot right after school, especially when his sister is watching television. In doing a functional analysis, we look for antecedents (things that come before the tic) and consequences (things that may be reinforcing the tic). Antecedents 1) Billy s tics get worse when anxious 2) Billy tics more in the den Consequences 1) Teasing sister is sent to room 2) Billy gets mom s love and attention Billy s tics are reinforced 3) Billy gets TV to himself 38

Function-Based Interventions After specific environmental variables are identified in the functional assessment, interventions are developed to decrease the effect of or contact with that variable Antecedents Functional Intervention 1) Anxiety Teach relaxation strategies 2) In the den after school Change setting Consequences 1) Teasing sister sent to room Sister stays in room and is asked to apologize 2) Mom comforts Billy Mom no longer comforts Billy 3) Billy gets TV to himself Mom turns TV off to provide Billy an opportunity practice his tic management strategies (e.g., a quiet place to tic, or habit reversal procedures) 39

Managing Internal Environment Premonitory Urge Tic X Relief Creates habituation to Premonitory Urge Negative Reinforcement 40

Changing Internal Environment Habit reversal training Forces habituation to the premonitory urge Designed to disrupt a habitual motor pattern after it has started 41

Habit Reversal-What Is It? Multi-component treatment (Azrin & Nunn, 1973) Used to treat tics 3 main components Awareness Training Competing Response Training Social Support 42

Does HRT Work? HRT has been studied for over 30 years using small-n and group experimental designs Considered an effective treatment for tics according to APA Division 12 Criteria (Cook & Blacher, 2007) To date, 6 Randomized Controlled Trials (RCTs) have been conducted N s have ranged from 10-42 Adults and children have been studied Controls have either been wait list, supportive therapy, or another behavioral treatment Results have all shown separation from waitlist or supportive therapy 43

Comprehensive Behavioral Intervention for Tics Study (CBITS) Child Study: 126 children (ages 9-17) with TS/CTD Participating Sites (40 at each of 3 sites) UCLA (Child: J. Piacentini, PI) Johns Hopkins University (Child: J. Walkup, PI) U. of Wisconsin Milwaukee (Child; D. Woods, PI) Mass General Hospital/Harvard (Adult: S. Wilhelm, PI) Yale Child Study Center (Adult: L. Scahill, PI) U. of Texas Health Sciences Center (Adult: A. Peterson, PI) Funded by NIMH through two different mechanisms (R01 to TSA) 44

CBITS Study Design Assessment Schedule: Week: 0 5 10 23 36 CBIT 126 Subjects with TS or CTD Booster Booster Booster Psychoeducation Support Booster Booster Booster

CBIT Components Study Treatments Psychoed/Support Components Psychoeducation Habit Reversal Therapy Functional Intervention Reward System Relaxation Training Phenomenology of TS Prevalence of TS Natural History of TS Common Comorbidities Causes of TS Psychosocial Impairments Nonspecific Support 46

CBITS Eligibility Criteria Inclusion Age 9 to 17 (child) or >16 (adult) Primary diagnosis of DSM-IV-TR TS or Chronic Tic Disorder CGI-Severity > 3 YGTSS Total Score > 14 Unmedicated or stable medication Patient speaks fluent English Informed consent

Exclusion CBITS Eligibility Criteria YGTSS Total Score > 30 (unless approved by caseness panel- 15 child cases of YGTSS >30 were approved: range = 31-42) IQ < 80 CGI-Severity < 3 Excessive/problematic substance use or CD past 3 months Lifetime diagnosis of DSM-IV PDD, Mania, Psychotic Disorder Any serious medical or psychiatric illness requiring immediate treatment other than provided in CBITS protocol Previous treatment with 4 or more sessions of HRT

Primary Outcome Measures Clinical Global Impression (CGI) Improvement Scale (1-7) YGTSS- Total Tic Score (0-50) YGTSS- Impairment (0-50)

CONSORT: Study Flow-Child PHASE 1-ACUTE OUTCOMES PHASE 2- LONG-TERM OUTCOMES Consented and Screened N = 177 Ineligible = 39 Presumed eligible but declined = 13 CBIT Phase 1 Responders N = 32/61 PST Phase 1 Responders N = 12/65 Randomized N = 126 Completed 3-mo follow-up Completed 3-mo follow-up N = 28/32 N = 11/12 CBIT N= 61 PST N= 65 Exited N = 6 Exited N = 7 Completed 6-mo follow-up N = 23/32 Completed 6-mo follow-up N = 8/12 Completed Phase I N = 55 Completed Phase I N = 58 Analyzed N = 61 Analyzed N = 65

Sample Characteristics- Child CBIT PST N=61 N=65 Mean Age (SD) 11.6 (2.3) 11.7 (2.3) Gender (% Male) 75.4% 81.5% WASI IQ (M, SD) 111.7 (13.5) 108.6 (14.0) Stable Tic Meds at Entry (%) 36.7% 40.3% Two Parent Family (%) 82.0% 87.7% Father s Occupation 60.7% 61.5% (% Professional)

Diagnostic Status CBIT PST Tic Disorder (%) Tourette Disorder 91.8 95.4 Chronic Motor Tic 6.6 4.6 Chronic Vocal Tic 1.6 0.0 Other Diagnoses (%) ADHD 32.8 20.0 OCD 13.1 24.6 Generalized Anxiety 16.4 23.1 Separation Anxiety 9.8 7.7 Social Anxiety 21.3 21.5 Other 14.8 12.3

CGI-Improvement Acute Phase Comparison *CBIT>PST, p<.0001 Medication status did not moderate outcome

YGTSS-Total Tic Score (Adjusted Means) Acute Phase Comparison *CBIT<PST, p<.01-10 week Effect Size d=.68 Medication status did not moderate outcome

YGTSS-Impairment (Adjusted Means) Acute Phase Comparisons *CBIT<PST, p<.01-10 Week Effect Size d=.57 Medication status did not moderate outcome

Maintenance of Responder Status (CGI-I): Completer

CBCL-Total Problems T-Scores Week 10 CBIT Responders Through Follow-up BL> 6-month 10 week > 6-month

SCARED Total Scores Week 10 CBIT Responders Through Follow-up BL> 3-month BL> 6-month

DBRS Scores Week 10 CBIT Responders Through Follow-up BL> 6-month

Benchmarking CBIT Efficacy

Benchmarking Acute Phase CBIT Efficacy Comparison YGTSS Total Effect RCT N Group Score (% ) Size (d) Active Comp CBIT 126 PST 31% 14% 0.7 (Piacentini et al., 2010) Risperidone 34 PBO 36% 9% 1.0 (Scahill et al., 2003) Ziprasidone 28 PBO 35% 7% 0.9 (Sallee et al., 2000)

Adverse Events by Treatment Group CBIT N (%) Control N (%) P-value Upper Respiratory Infection 21 34.4 27 41.5 NS Irritability, explosive behavior 10 16.4 10 15.4 NS Headache 10 16.4 14 21.5 NS Muscle or joint pain 9 14.8 13 20.0 NS Accidental injury 7 11.5 19 29.2 0.02 Anxiety and nervousness 4 6.6 3 4.6 NS Disruptive behavior 4 6.6 4 6.2 NS Sore Throat 4 6.6 7 10.8 NS Nausea, vomiting 2 3.3 5 7.7 NS Stomach Discomfort 2 3.3 9 13.8 0.06 Dermatological problems 1 1.6 5 7.7 NS Tic worsening 1 1.6 4 6.2 NS Tiredness, fatigue 1 1.6 4 6.2 NS

Adverse Events by Treatment Group CBIT N (%) Control N (%) P-value Upper Respiratory Infection 21 34.4 27 41.5 NS Irritability, explosive behavior 10 16.4 10 15.4 NS Headache 10 16.4 14 21.5 NS Muscle or joint pain 9 14.8 13 20.0 NS Accidental injury 7 11.5 19 29.2 0.02 Anxiety and nervousness 4 6.6 3 4.6 NS Disruptive behavior 4 6.6 4 6.2 NS Sore Throat 4 6.6 7 10.8 NS Nausea, vomiting 2 3.3 5 7.7 NS Stomach Discomfort 2 3.3 9 13.8 0.06 Dermatological problems 1 1.6 5 7.7 NS Tic worsening 1 1.6 4 6.2 NS Tiredness, fatigue 1 1.6 4 6.2 NS

Summary of CBIT Findings CBIT is more efficacious than PST for Reducing tic severity Reducing tic-related impairment CBIT efficacy similar to meds for tics Roughly similar symptom reduction rates Lower Effect Size (use of active comparison group) More favorably safety profile CBIT responders maintain their gains and improve in other areas of functioning 6-mo after treatment

If Behavior Therapy for Tics is So Promising. Dissemination How do we teach therapists to do this? Referral problem Neurologists/pediatricians usually get referral Beliefs about negative effects of behavior therapy

Beliefs Inhibiting Use of Behavior Therapy for Tics Rebound effects Trying to stop tics makes you tic more Symptom substitution Stopping one tic makes others worse, or are replaced by new ones Ability to attend to other things will be greatly diminished because of focus on tics

Is there a Rebound Effect? Study 1 7 children with TS Three conditions Baseline Reinforced suppression Rebound evaluation All conditions were 5 min Tics were reduced in suppression condition Rebound did not occur % intervals w/ tics 50 45 40 35 30 25 20 15 10 5 0 Himle & Woods (2006) Behaviour Research and Therapy Baseline DRO Rebound DRO Rebound

Is there a Rebound Effect? Study 2 10 9 8 7 6 5 4 3 2 1 0 BL 5-MIN REB1 25-MIN REB2 40-MIN REB3 13 children with TS or CTD Mean YGTSS = 28.2 Woods et al. (2008). Journal of Abnormal Child Psychology Funded by TSA

Does Symptom Substitution Occur? Multiple BL Across 5 Subjects with TS Initial assessment followed by in home recordings Habit Reversal (Woods, 2001) 1, 1 hr session; 2, 1/2 hour booster sessions 1 session per week for 3 consecutive weeks Awareness training, competing response training, social support training Woods et al. (2003). Journal of Applied Behavior Analysis

P e r c e n t o f i n t e r v a l s w i t h t i c s 1 0 0 8 0 6 0 B a s e l in e v o c a l H a b it R e v e r s a l f o r V o c a l T ic s D o n F o l lo w - up 4 0 m o t o r 2 0 0 6 0 4 0 J o h n B o o s te r S e s s io n 2 0 0 8 0 6 0 B e n 4 0 2 0 0 6 0 4 0 R a o u l 2 0 0 8 0 6 0 F r a n k 4 0 2 0 0 1 3 5 7 9 1 1 1 3 1 5 1 7 1 9 F U A s s e s s m e n t s e s s i o n s Woods et al. (2003). Journal of Applied Behavior Analysis

Tic Frequency Distraction + Suppression Suppression Baseline Can Tics be Stopped While Doing Other Things? 9 children with TS were studied Tics were lower when children were asked to suppress, regardless of whether or not they were distracted while suppressing Reduction during suppression was 86% from BL Reduction during distraction was 76% from BL 45 40 35 30 25 20 15 10 5 0 Conelea & Woods (2010). Behaviour Research and Therapy

Hits out of 42 Distraction Baseline Does Stopping Tics Impact Ability to Do Other Things? Accuracy was reduced 11% on CPT when in the suppression+distraction condition 45 40 35 30 25 20 15 10 5 0

Summary/Future Directions HRT/Behavior Therapy is a promising treatment for TS Still need Predictors of response to treatment Mechanism of change data Overcoming barriers to implementation Telehealth service delivery Computerized therapist training packages Educating appropriate care providers about availability of BT 73

Evaluating Dissemination Strategies for Habit Reversal Training: Initial Development and Testing of a Telehealth Approach M. Himle University of North Dakota University of Utah D. Woods University of Wisconsin-Milwaukee Project funded by the TSA

For more information, please go to the main website and browse for workshops on this topic or check out our additional resources. Additional Resources Online resources: 1. National Tourette Syndrome Association website: http://www.tsa-usa.org/ 2. Society of Clinical Child and Adolescent Psychology website: http://effective childtherapy.com Selected Peer-reviewed Journal Articles: 1. Cook, C. R. & Blacher, J. (2007). Evidence-based psychosocial treatments for tic disorders. Clinical Psychology: Science and Practice, 14, 252 267. 2. Piacentini, J., Woods, D.W., Scahill, L., Wilhelm, S., Peterson, A.L., Chang, S., & Walkup, J.T. (2010). Behavior therapy for children with Tourette disorder: A randomized controlled trial. Journal of the American Medical Association, 303(19), 1929-1937. 3. Sallee, F.R., Kurlan, R., Goetz, C.G., Singer, H., Scahill, L., Law, G., & Chappell, P.B. (2000). Ziprasidone treatment of children and adolescents with tourette's syndrome: A pilot study. Journal of the American Academy of Child & Adolescent Psychiatry, 39(3), 292-299. 4. Scahill, L., Leckman, J.F., Schultz, R.T., Katsovich, L., Peterson, B.S. (2003). A placebo-controlled trial of risperidone in Tourette syndrome. Neurology, 60 (7), 1130-1135. 5. Silva, R.R., Munoz, D.M., Barickman, J. & Friedhoff, A.J. (1995). Environmental factors and related fluctuation of symptoms in children and adolescents with Tourette's disorder. Journal of Child Psychology Psychiatry, 36, 305 312. 6. Woods, D.W., Himle, M.B., Miltenberger, R.G., Carr, J.E., Osmon, D.C., Karsten, A.M., & Bosch A. (2008). Durability, negative impact, and neuropsychological predictors of tic suppression in children with chronic tic disorder. Journal of Abnormal Child Psychology, 36(2), 237-245,

Full Reference List Keynote: Evidence-Based Treatment of Tourette s Syndrome and Tic Disorders Websites: National Tourette Syndrome Association: http://www.tsa-usa.org/ Peer Reviewed Journal Articles: Azrin, N.H. & Nunn, R.G. (1973). Habit-reversal: A method of eliminating nervous habits and tics. Behaviour Research and Therapy, 11 (4), 619-628. Commander, M., Corbett, J., Prendergast, M., & Ridley, C. (1991). Reflex tics in two patients with Gilles de la Tourette syndrome. British Journal of Psychiatry, 159, 877-879. Cook, C. R. & Blacher, J. (2007). Evidence-based psychosocial treatments for tic disorders. Clinical Psychology: Science and Practice, 14, 252 267. Himle M.B., Woods D.W., Piacentini J.C., & Walkup J.T. (2006). Brief review of habit reversal training for Tourette syndrome. Journal of Child Neurology, 21, 719 725. Piacentini, J., Woods, D.W., Scahill, L., Wilhelm, S., Peterson, A.L., Chang, S., Walkup, J.T. (2010). Behavior therapy for children with Tourette disorder: A randomized controlled trial. Journal of the American Medical Association, 303(19), 1929-1937. Sallee, F.R., Kurlan, R., Goetz, C.G., Singer, H., Scahill, L., Law, G., Chappell, P.B. (2000). Ziprasidone treatment of children and adolescents with tourette's syndrome: A pilot study. Journal of the American Academy of Child & Adolescent Psychiatry, 39(3), 292-299. Scahill, L., Leckman, J.F., Schultz, R.T., Katsovich, L., Peterson, B.S. (2003). A placebo-controlled trial of risperidone in Tourette syndrome. Neurology, 60 (7), 1130-1135. Silva, R.R., Munoz, D.M., Barickman, J. & Friedhoff, A.J. (1995). Environmental factors and related fluctuation of symptoms in children and adolescents with Tourette's disorder. Journal of Child Psychology Psychiatry, 36, 305 312. Surwillo, W.W., Shafii, M., & Barrett, C.L. (1978). Gilles de la Tourette syndrome: A 20-month study of the effects of stressful life events and haloperidol on symptom frequency. Journal of Nervous & Mental Disease, 166 (11), 812-816. Watson, T. S. & Sterling, H. E. (1998). Brief functional analysis and treatment of a vocal tic. Journal of Applied Behavior Analysis, 31, 471-474. Woods, D.W., Himle, M.B., Miltenberger, R.G., Carr, J.E., Osmon, D.C., Karsten, A.M., Bosch A. (2008). Durability, negative impact, and neuropsychological predictors of tic suppression in children with chronic tic disorder. Journal of Abnormal Child Psychology, 36(2), 237-245. Woods, D. W., Twohig, M. P., Flessner, C. A., & Roloff, T. J. (2003). Treatment of vocal tics in children with Tourette syndrome: Investigating the efficacy of habit reversal. Journal of Applied Behavior Analysis, 36, 109 112. Woods, D. W., Watson, T. S., Wolfe, E., Twohig, M. P., & Friman, P. C. (2001). Analyzing the influence of tic-related talk on vocal and motor tics in children with Tourette s syndrome. Journal of Applied Behavior Analysis, 34, 353-356. Retrieved from http://www.effectivechildtherapy.fiu.edu