A Neurocognitive Comparison of Pediatric Obsessive-Compulsive Disorder and Trichotillomania (Hair Pulling Disorder)

Clinical Characteristics of Youth with Trichotillomania (Hair-Pulling Disorder) and Excoriation (Skin-Picking) Disorder

Body-focused repetitive disorders (BFRBDs) are understudied in youth and understanding of their underlying mechanisms is limited. This study evaluated BFRBD clinical characteristics, and two factors commonly implicated in their maintenance - emotion regulation and impulsivity - in 53 youth aged 11 to 17 years: 33 with BFRBDs and 20 controls. Evaluators administered psychiatric diagnostic interviews. Participants rated BFRBD severity, negative affect, quality of life, family functioning, emotion regulation, distress tolerance, and impulsivity. Youth with BFRBDs showed poorer distress tolerance and quality of life, and higher impulsivity and negative affect than controls, with no differences in family impairment. BFRBD distress/impairment, but not BFRBD severity, correlated with anxiety and depression, and poorer distress tolerance. Findings suggest youth with BFRBDs show clinical patterns aligning with prior research; highlight the role of distress tolerance in child BFRBDs; and suggest the utility of acceptance and mindfulness-based therapies for unpleasant emotions in BFRBDs. Continued research should evaluate factors underlying BFRBDs in youth.

Cognition in trichotillomania: a meta-analysis

OBJECTIVE

Trichotillomania (TTM) is a mental health disorder characterized by repetitive urges to pull out one's hair. Cognitive deficits have been reported in people with TTM compared to controls; however, the current literature is sparse and inconclusive about affected domains. We aimed to synthesize research on cognitive functioning in TTM and investigate which cognitive domains are impaired.

METHODS

After preregistration on the International Prospective Register of Systematic Reviews (PROSPERO), we conducted a comprehensive literature search for papers examining cognition in people with TTM versus controls using validated tests. A total of 793 papers were screened using preestablished inclusion/exclusion criteria, yielding 15 eligible studies. Random-effects meta-analysis was conducted for 12 cognitive domains.

RESULTS

Meta-analysis demonstrated significant deficits in motor inhibition and extradimensional (ED) shifting in people with TTM versus controls as measured by the stop-signal task (SST) (Hedge's g = 0.45, [CI: 0.14, 0.75], p = .004) and ED set-shift task (g = 0.38, [CI: 0.13, 0.62], p = .003), respectively. There were no significant between-group differences in the other cognitive domains tested: verbal learning, intradimensional (ID) shifting, road map spatial ability, pattern recognition, nonverbal memory, executive planning, spatial span length, Stroop inhibition, Wisconsin card sorting, and visuospatial functioning. Findings were not significantly moderated by study quality scores.

CONCLUSIONS

Motor inhibition and ED set-shifting appear impaired in TTM. However, a cautious interpretation of results is necessary as samples were relatively small and frequently included comorbidities. Treatment interventions seeking to improve inhibitory control and cognitive flexibility merit exploration for TTM.

Impulsivity in adolescent girls diagnosed with trichotillomania: an evaluation of clinical and neuropsychological characteristics

The aim of this study is to compare the clinical and neuropsychological features of impulsivity in adolescent girls with trichotillomania (TTM) and healthy controls, and to assess the relationships between the severity of TTM and the impulsivity/concomitant symptoms of anxiety and depression. The study sample consisted of 43 adolescent girls who were 12 to 18 years old. The Kiddie-Schedule for Affective Disorders and Schizophrenia for School Age Children-Present and Lifetime Version DSM-5 (K-SADS-PL) was administered to the adolescents and their parents. All of the participants completed a sociodemographic data form, the Revised Children's Anxiety and Depression Scale-Child Version (RCADS-CV), the Barratt Impulsiveness Scale-Brief (BIS-Brief), and the Massachusetts General Hospital Hairpulling Scale (MGH-HPS). The Eriksen Flanker task, the Stop Signal Reaction Time (SSRT) task, the Go/No-Go task, and the Balloon Analog Risk Task (BART) were used to assess behavioral impulsivity. The adolescents with TTM reported higher levels of impulsivity and anxiety/depression symptoms than the healthy controls, and they also performed worse on the behavioral tasks. While there were no relationships between clinical and behavioral impulsivity and TTM severity, social anxiety symptoms were the most important predictor of the severity of TTM. It seems important to better understand the role of impulsivity in the onset and persistence of TTM symptoms in adolescents.

Clinical Characteristics, Sleep, and Temperament in Infants and Young Children with Problematic Hair Pulling and Skin Picking

Background

This study examined clinical characteristics of problematic hair pulling (HP) and skin picking (SP) in infants and young children and their association with self-soothing, sleep, and temperament.

Methods

An internet survey of parents/caregivers of 0-5-year-olds (n = 384 with data analyzed, of whom 26 experienced HP, 62 experienced SP, and 302 were controls free of HP and SP) assessed demographics and medical history, HP and SP characteristics, contextual factors, self-soothing, sleep patterns, and temperament. Participants were recruited through both HP and SP advocacy and support webpages and general webpages (e.g., parenting groups). Descriptive statistics, chi-square tests of independence, independent samples t-test clinically characterized HP, SP, and control groups. Logistic regression and one-way analysis of covariance controlled for sex and age in analyses.

Results

HP and SP rates were 6.1% (n = 26) and 14.5% (n = 62), respectively. SP presented in 23.1% of children with HP, and HP presented in 9.7% of children with SP. Mean HP and SP onset occurred at 12.2 (SD = 11.2) and 24.1 (SD = 15.8) months, respectively. Contextual factors, including boredom, upset, and awake-in-bed were common in HP and SP. Common caregiver responses included distracting the child, moving the hand away, and telling the child to stop. Few caregivers sought professional help for the child. Children with HP engaged in more hair twirling than controls, and children with SP engaged in more nail biting than controls. Children with HP, but not SP, had more sleep disturbance than controls. In terms of temperament, children with HP displayed sensitivity to stimuli, children with SP exhibited low persistence, and both HP and SP groups displayed serious, observant mood relative to controls.

Conclusions

Findings expand clinical understanding of HP and SP in children aged 0-5 and provide targets (contextual factors, sleep, sensory sensitivity, persistence, and mood) for behavioral interventions. Low rates of treatment seeking highlight the need for expansion of clinical guidelines for HP and SP in this age range.

Neural Correlates of Executive Functioning in Anorexia Nervosa and Obsessive-Compulsive Disorder

Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) are commonly reported to co-occur and present with overlapping symptomatology. Executive functioning difficulties have been implicated in both mental health conditions. However, studies directly comparing these functions in AN and OCD are extremely limited. This review provides a synthesis of behavioral and neuroimaging research examining executive functioning in AN and OCD to bridge this gap in knowledge. We outline the similarities and differences in behavioral and neuroimaging findings between AN and OCD, focusing on set shifting, working memory, response inhibition, and response monitoring. This review aims to facilitate understanding of transdiagnostic correlates of executive functioning and highlights important considerations for future research. We also discuss the importance of examining both behavioral and neural markers when studying transdiagnostic correlates of executive functions.

Neuropsychological performance in youth with obsessive-compulsive disorder

There is a paucity of literature on neuropsychological functions in youth with obsessive-compulsive disorder (OCD). Most studies have small sample sizes and have yielded inconsistent results. A recent meta-analysis failed to identify any significant impairments. We studied neuropsychological functions (attention, verbal fluency, working memory, set-shifting, response inhibition, planning and visuospatial abilities) in a large sample of youth with OCD (n = 97) in comparison with controls who did not have OCD (n = 50). After controlling for the confounding effects (age, sex, severity of depression and anxiety, presence of comorbid attention-deficit hyperactivity disorder, any tic disorder, number of comorbidities, and non-verbal intelligence measured by the standard progressive matrices), the youth with OCD significantly underperformed with large effect sizes compared to controls, only on the test of 'behavioral reversal', measured by the Object Alternation Test (trials to reach criterion p < 0.001, Cohen's d = 1.49; perseverative errors p < 0.001, Cohen's d = 1.31). Patients also underperformed on a task of planning, but it was statistically insignificant. Certain comorbid disorders, antipsychotic use and age of onset did not influence neuropsychological performance significantly. Our study demonstrates that youth with OCD may have impaired 'set-shifting' in the form of 'behavioral reversal' and possibly planning, findings broadly consistent with the literature in adults and with the fronto-striatal model of OCD. It is possible that youth may accumulate more neuropsychological impairments over a period, as the illness continues into adulthood.