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.

Psychiatric Comorbidities in Pediatric Trichotillomania: A Multicenter Cohort Study.

BACKGROUND: Trichotillomania (TTM) significantly increases the risk of psychiatric comorbidities. Sparse research in pediatric populations necessitates larger studies to assess these risks. This study investigates the risk of developing psychiatric comorbidities in pediatric TTM patients. METHODS: This case-control study assessed pediatric patients (< 18 years old) with TTM diagnosed between May 18, 2013, and January 1, 2024, using US-based data from the TriNetX global research network. TTM patients (ICD-10 diagnostic category F63.3) aged 18 years or younger at diagnosis and control patients (ICD-10 code Z00.129) matched for age, sex, race, and ethnicity were assessed. Propensity score matching yielded 16,590 patients in each cohort. The analysis assessed subsequent diagnoses of ADHD, conduct disorders, tic disorders, obsessive-compulsive disorder, anxiety disorders, dissociative, stress-related, and somatoform disorders, mood disorders, and suicide attempts compared to controls. RESULTS: TTM patients under 18 years exhibited significantly greater risks of subsequent diagnoses for ADHD (OR: 2.002; CI 1.841-2.178; p < 0.001), conduct disorders (OR: 3.668; 3.2-3.668; p < 0.0001), tic disorders (OR: 2.247; 1.826-2.765; p < 0.0001), obsessive-compulsive disorder (OR: 11.047; 8.822-13.832; p < 0.0001), anxiety disorders (OR: 3.583; 3.387-3.7; p < 0.0001), dissociative, stress-related, and somatoform disorders (OR: 6.179; 3.935-9.701; p < 0.0001), mood disorders (OR: 2.476; 2.288-2.68; p < 0.0001), and suicide attempts (OR: 1.81; 1.121-2.924; p = 0.0139) compared to controls. TTM patients had the greatest risk of psychiatric diagnosis 1 year postindex event. CONCLUSIONS: Pediatric TTM patients have higher psychiatric comorbidity risks, necessitating timely intervention and comprehensive management. Dermatologists can facilitate access to behavioral and pharmacological care, enhancing patient outcomes.

Sensory Overresponsivity and Symptoms Across the Obsessive-Compulsive Spectrum: Web-Based Longitudinal Observational Study.

BACKGROUND: Sensory overresponsivity (SOR) has emerged as a potential endophenotype in obsessive-compulsive disorder (OCD), but few studies have examined SOR in relation to the major symptom dimensions of OCD and to symptoms across the full obsessive-compulsive (OC) symptom spectrum. OBJECTIVE: This study had 2 main objectives. First, we examined the psychometric properties of the SOR Scales in a community-based sample of Spanish adolescents and adults. Second, we identified how SOR difficulties are related to symptoms across the full OC spectrum (eg, OC, body dysmorphic, hoarding, skin-picking, and hair-pulling symptoms), including the heterogeneity of OC symptoms. METHODS: We translated the SOR Scales into Spanish-a measure that assesses SOR across the 5 sensory modalities-and created a web-based version of the measure. A sample of 1454 adolescents and adults (mean age 23.84, SD 8.46 years) participated in the study, and 388 (26.69%) participants completed the survey twice (approximately 8 months apart). The survey also contained a web-based measure that assesses symptoms across the full OC spectrum: harm and checking, taboo obsessions, contamination or cleaning, symmetry and ordering, body dysmorphic, hoarding, hair-pulling, and skin-picking symptoms. RESULTS: The psychometric properties of the SOR Scales were excellent, and the test-retest reliability was adequate. All types of SOR were related to all major symptom dimensions of OCD and to all OC spectrum symptoms. CONCLUSIONS: SOR across the sensory modalities can be validly assessed using a web-based measure. SOR emerged as a pure transdiagnostic phenomenon in relation to symptoms across the OC spectrum, with no specific sensory modality being more strongly related to OC symptoms. SOR can shed much needed light on basic mechanisms that are important for the onset and maintenance of OC spectrum symptoms, and this study shows that large-scale web-based studies can aid in this endeavor. Future studies should examine whether SOR precedes or emerges alongside OC symptoms.

Sociodemographic variables, clinical characteristics, and treatments in children with trichotillomania in terms of age and gender: a multicenter study.

OBJECTIVE: Although trichotillomania (TTM) is a common, typically pediatric-onset disorder, data on the phenomenology of TTM in children, accompanying comorbid psychiatric disorders, and treatment options are extremely limited. In our study, it was aimed to investigate these variables and related factors in patients undergoing psychiatric evaluation and follow-up. METHOD: The study included 79 children and adolescents between the ages of 4 and 17 who were diagnosed with TTM and followed up in four different Child and Adolescent Psychiatry outpatient clinics between 2015 and 2020. The sociodemographic characteristics of these patients, clinical features of the disease, comorbid psychiatric disorders, and treatment approaches have been studied. RESULTS: Our results showed that TTM was more common in girls, hair and eyebrow plucking was the most common, and symptoms and features accompanying TTM changed with age, but not with gender. Again, 79.7% of these children had at least one psychiatric comorbid disorder (most common being anxiety disorders and Attention Deficit/Hyperactivity Disorder), comorbidity was closely related to TTM severity, 93.7% used at least one pharmacotherapeutic agent, and positive response rates to treatment were found to be low. Moreover, TTM severity was found to increase with age and disease duration. CONCLUSION: Study findings support that clinical presentation, disease severity and comorbidity rates may change with age in children and adolescents with TTM, and early intervention is important to prevent clinical progression/worsening and mental health sequela.

Sleep Disturbances in Pediatric Body-Focused Repetitive Behaviors: A Preliminary Investigation.

Body-focused repetitive behaviors (BFRBs) are repeated actions to one's body resulting in physical damage. Limited research has examined sleep, a known factor in psychological health, within the context of pediatric BFRBs. The current study sought to explore the connection between disordered sleep and BFRBs in a community sample. Aim 1 of the study was to determine the predictive power of group membership [control group (no BFRB symptoms reported), subthreshold BFRB group (mild BFRB symptoms reported; severity score of 2 or less out of 9), and those with symptoms characteristic of BFRBs (more than mild BFRB symptoms reported; severity score of 3 or higher out of 9)] for level of sleep disturbance. A hierarchical regression revealed that there was a significant effect of group membership after controlling for anxiety (F (3, 410) = 152.976, p < .001). Aim 2 of the study was to test whether there was a relationship between sleep disturbance and BFRB severity. The hierarchical regression revealed that at Step 1, anxiety accounted for 23.1% of the variance in BFRB severity (ß = 0.48, t = 8.87, p < 0.001). At Step 2, sleep disturbance total score accounted for an additional 7.2% of the variance, suggesting this variable makes a unique contribution to overall BFRB severity (SDSC: ß = 0.40, t = 5.18, p < 0.001). The findings of this study suggest that sleep could be a clinical factor to consider when conceptualizing a child with BFRBs.

Usefulness of three-dimensional computed tomography venography differentiating calvarium subperiosteal hematoma crossing the suture lines due to hair pulling from subgaleal hematoma: case report and review of the literature.

This case showed a 13-year-old boy presented with calvarium subperiosteal hematoma crossing the suture lines caused by hair pulling, and 3D-CTV can differentiate calvarium subperiosteal hematoma crossing the suture lines from subgaleal hematoma. He was treated successfully.

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.

Sex Differences in Age at Onset and Presentation of Trichotillomania and Trichobezoar: A 120-Year Systematic Review of Cases.

Trichotillomania (hair-pulling disorder) has high female preponderance. It has been suggested that onset in early childhood represents a distinct developmental subtype that is characterized by higher prevalence of males compared to later onset cases. However, the empirical literature is scarce. We conducted a systematic review of case reports to examine the distribution of age at onset/presentation in males and females with trichotillomania or trichobezoar (a mass of hair in the gastrointestinal tract resulting from ingesting hair). We identified 1065 individuals with trichotillomania and 1248 with trichobezoar. In both samples, males, compared to females, had earlier age at presentation and greater proportion of cases in early childhood. These sex differences remained after potential confounding variables were accounted for. The results showed similar sex differences for age at onset, which was reported in 734 and 337 of the trichotillomania and trichobezoar cases, respectively. The findings may reflect neurodevelopmental underpinnings in early childhood trichotillomania.

Hair-pulling disorder (Trichotillomania): Etiopathogenesis, diagnosis and treatment in a nutshell.

Hair-pulling disorder (Trichotillomania) is a disabling mental disorder. Patient's behavior is characterized by the recurrent pulling of own hair with hair loss and a marked dysfunction in various areas of daily life. Trichotillomania is a relatively common disorder with pediatric onset, often associated with significant morbidity, comorbidity, and functional decline. Surprisingly, children or adolescents have been little studied in the research studies on the pathophysiology and psychopathology of trichotillomania. Furthermore, more evidences regarding the effective and evidence-based pharmacological interventions for the treatment of this condition are encouraged. This narrative review will report on the etiopathogenesis and clinical manifestations of trichotillomania including criteria for diagnosis and treatment issues of this complex mental disorder.

Diagnostic Accuracy of Trichoscopy in Trichotillomania: A Systematic Review.

Trichotillomania is formally classified as a mental health disorder, but it is commonly diagnosed by dermatologists. The aim of this systematic review is to assess the diagnostic value of trichoscopy in diagnosing trichotillomania. The analysis identified the 7 most specific trichoscopic features in trichotillomania. These features had the following prevalence and specificity: trichoptilosis (57.5%; 73/127 and 97.5%, respectively), v-sign (50.4%; 63/125 and 99%), hook hairs (43.1%; 28/65 and 100%), flame hairs (37.1%; 52/140 and 96.5%), coiled hairs (36.8%; 46/125 and 99.6%), tulip hairs (36.4%; 28/77 and 89.6%), and hair powder (35.6%; 42/118 and 97.9%). The 2 most common, but least specific, features were broken hairs and black dots. In conclusion, trichoscopy is a reliable new diagnostic method for hair loss caused by hair pulling. Trichoscopy should be included as a standard procedure in the differential diagnosis of trichotillomania in clinical practice.

ACT-enhanced group behavior therapy for trichotillomania and skin-picking disorder: A feasibility study.

OBJECTIVE: To evaluate the feasibility and efficacy of ACT-enhanced Group Behavior Therapy (AEGBT) for mixed diagnosis groups including patients with trichotillomania (TTM) and skin-picking disorder (SPD) in routine psychiatric care. METHOD: Adult patients (N = 40) with TTM and/or SPD received 10 weeks of AEGBT followed by five booster sessions. The primary outcome measure for TTM was the Massachusetts General Hospital Hairpulling Scale (MGH-HPS) and for SPD the Skin Picking Scale-Revised (SPS-R), assessed at posttreatment and at booster sessions. RESULTS: Results showed significant reductions in hair pulling and skin-picking severity from baseline to posttreatment and large effect sizes at posttreatment. Improvements remained significant at the 12-month follow-up for patients with SPD, but not for patients with TTM. Group attendance was high and few patients dropped out from treatment. The group format enabled therapists to see 25% more patients compared with an individual format. CONCLUSION: The results provide initial support for the feasibility and efficacy of an adapted treatment approach for TTM and SPD.

Trichotillomania (hair pulling disorder): Clinical characteristics, psychosocial aspects, treatment approaches, and ethical considerations.

Trichotillomania (hair pulling disorder) is a fairly common but underreported disorder characterized by recurrent episodes of pulling hair from different parts of the body. Currently classified in Diagnostic and Statistical Manual of Psychiatric Disorders (DSM-5) under the heading of the "Obsessive-compulsive spectrum and related disorders." The estimated prevalence data suggest that 0.5-2% of the general population suffers from this disorder. Stress and anxiety are directly correlated to the production of trichotillomania symptoms. The psychosocial aspects of trichotillomania are greatly underestimated, but recent literature suggests an increased interest in this neglected area. Although no FDA approved medications are available for the treatment of trichotillomania, a variety of medications including N-acetylcysteine have shown benefit in case reports. Combined liaison clinics, with an interdisciplinary approach, are highly advisable in the treatment of these cases.

The Beliefs in Trichotillomania Scale (BiTS): Factor analyses and preliminary validation.

OBJECTIVES: The role of cognitions and beliefs in trichotillomania (TTM; hair pulling disorder) has been the subject of only limited investigation. This study aimed to develop and validate the Beliefs in TTM Scale (BiTS). METHODS: A pool of 50 items based upon themes identified in previous research was administered online to 841 participants with and without self-reported problematic, non-cosmetic hair pulling behaviours. RESULTS: Exploratory and confirmatory factor analyses conducted in randomly split-halves of the sample supported retention of 14 items comprising three factors: negative self-beliefs, low coping efficacy, and perfectionism. CONCLUSIONS: The BiTS demonstrated satisfactory psychometric properties and all three subscales significantly correlated with greater hair pulling severity. Negative self-beliefs predicted hair pulling severity over and above mood symptoms, suggesting the importance of addressing self-construals in psychological treatments for TTM. Validation in a clinician diagnosed sample is required. PRACTITIONER POINTS: Research supports cognitive therapies for treating trichotillomania (hair pulling disorder), although studies investigating the nature and role of cognitions and beliefs in this disorder have been lacking. This study developed and validated a self-report measure of three styles of beliefs most relevant to trichotillomania: negative self-beliefs, low coping efficacy, and perfectionism. Negative self-beliefs predicted the severity of trichotillomania symptoms over and above depression and anxiety, suggesting such cognitions may not necessarily be due to comorbidities. Future research should validate the new measure in a clinician diagnosed sample, and therapies for trichotillomania may be enhanced by targeting shame specifically.

Prevalence and characteristics of hair plucking in captive bonobos (Pan paniscus) in North American zoos.

When primates exhibit hair loss and are observed to engage in self or social hair plucking (a rapid jerking away of the hair shaft and follicle by the hand or mouth, often accompanied by inspection, and consumption) the altered appearance, and behavior patterns are thought to reflect individual physiological, and psychological well-being. Hair loss and hair plucking occur in many captive primate species, including all of the great apes. We present the first survey of this behavior among captive bonobos (N = 88; 50 females and 38 males) in seven zoos in the United States. We found that 43% of the population engaged in this behavior pattern and discounting youngsters (who are not observed to hair pluck until the age of five), 58% of individuals hair plucked. Of the individuals who hair plucked, 97% engaged in social plucking, whereas 46% engaged in self-directed plucking. We regressed the occurrence of hair plucking with multiple predictor variables using binary logistic regression and multimodel inference to determine which predictors best explained the prevalence of self-directed and social plucking. We also analyzed publicly available data on hair plucking in captive chimpanzees. We found that the occurrence of another abnormal behavior, age, origin, and pelage condition best explained self-directed plucking in bonobos. Social plucking was explained by age, origin, pelage, and sex. Our analysis of chimpanzee hair plucking revealed that plucking is strongly influenced by rearing and sex. This study demonstrates that hair plucking is more prevalent in captive bonobos compared to captive chimpanzees and gorillas, however, the covariates associated with hair plucking for each species are different. Our data suggest a potential link between self-directed plucking and well-being. However, the higher prevalence and etiology of social hair plucking is more difficult to explain.

Prevalence and predictors of hair pulling disorder and excoriation disorder in Tourette syndrome.

Trichotillomania/hair pulling disorder (HPD) and excoriation/skin picking disorder (SPD) are childhood-onset, body-focused repetitive behaviors that are thought to share genetic susceptibility and underlying pathophysiology with obsessive-compulsive disorder (OCD) and Tourette syndrome (TS). We sought to determine the prevalence of DSM-5 HPD and SPD in TS patients, and to identify clinical factors most associated with their co-morbidity with TS. Participants included 811 TS patients recruited from TS specialty clinics for a multi-center genetic study. Patients were assessed using standardized, validated semi-structured interviews. HPD and SPD diagnoses were determined using a validated self-report questionnaire. HPD/SPD prevalence rates were calculated, and clinical predictors were evaluated using regression modeling. 3.8 and 13.0% of TS patients met DSM-5 criteria for HPD and SPD, respectively. In univariable analyses, female sex, OCD, and both tic and obsessive-compulsive symptom severity were among those associated with HPD and/or SPD. In multivariable analyses, only lifetime worst-ever motor tic severity remained significantly associated with HPD. Female sex, co-occurring OCD, ADHD, and motor tic severity remained independently associated with SPD. This is the first study to examine HPD and SPD prevalence in a TS sample using semi-structured diagnostic instruments. The prevalence of HPD and SPD in TS patients, and their association with increased tic severity and co-occurring OCD, suggests that clinicians should screen children with TS and related disorders for HPD/SPD, particularly in females and in those with co-occurring OCD. This study also helps set a foundation for subsequent research regarding HPD/SPD risk factors, pathophysiology, and treatment models.

A Preliminary Investigation of Metacognitive Therapy and Habit Reversal as a Treatment for Trichotillomania.

BACKGROUND: Not all patients suffering from trichotillomania (TTM) recover completely using CBT and of those that do, only a few maintain their recovery over time. AIMS: The purpose of the present study was to investigate the effectiveness of metacognitive methods combined with habit reversal (MCT/HRT) in trichotillomania with a relatively long-term follow-up. METHOD: A case series (n = 8) and a randomized wait-list controlled trial (n = 34) design were conducted in this study. In the case series, three of the eight patients dropped out of the study. Therefore, TTM-related symptoms were evaluated in five patients suffering from TTM before and after brief metacognitive plus habit reversal therapy during 1-month, 6-month, and 12-month follow-ups. The treatment consisted of detached mindfulness (DM) techniques, ritual postponement and habit reversal training (HRT) in eight sessions. RESULTS: All patients were responders at post-treatment in case series. After the 12-month follow-up, the results were associated with higher pre-treatment levels of self-esteem and global functioning and lower pre-treatment levels of depression and anxiety with nearly complete abstinence from hair pulling immediately after treatment. A randomized wait-list controlled trial with experimental (n = 17) and waiting list group (n = 17) was then conducted to confirm the case series results. There were significant differences between the two groups regarding changes in MGH-HPS, Y-BOCS-TM, RSES, GAF, BDI, BAI and self-monitoring. Therefore, the MCT/HRT treatment was found to be more effective than the waiting list group. CONCLUSIONS: A combined treatment including metacognitive and habit reversal techniques is remarkably effective in patients with TTM.

Social hair pulling in captive rhesus macaques (Macaca mulatta).

Alopecia is common among captive populations of nonhuman primates. There are many potential causes of alopecia, including physiological conditions such as hormonal imbalance and infection, features of the captive environment such as housing type, ground substrate, and group density, as well as behavioral abnormalities such as self-plucking. A potential behavioral cause of alopecia in group-housed primates is social hair pulling, where one animal pulls hair from a conspecific. While social hair pulling has been conflated with overgrooming in some of the alopecia literature, other authors have categorized it as a form of aggression rather than a form of excessive grooming. In this study, we examined social hair pulling, grooming, and aggression within seven groups of rhesus macaques (Macaca mulatta) (N = 319). We took weekly 30-min behavioral observations on each group for one year to assess the patterns of hair pulling and grooming, which monkeys were receiving and initiating these behaviors, as well as aggression and other behaviors indicating dominance. We also assessed the amount of alopecia on each individual monthly. While grooming tended to be directed "up" the hierarchy (i.e., monkeys were more likely to groom animals of a higher rank than lower rank), most hair pulling was directed "down" the hierarchy. Further, hair pulling seldom co-occurred with aggressive behaviors, suggesting that it was not a form of aggression. Hair pulling also usually resulted in ingestion of the pulled hair. Hair pulling was correlated with alopecia; monkeys who were frequent recipients of hair pulling scored higher on monthly alopecia ratings than those who were less often observed having hair pulled. Our results suggest that social hair pulling is a behavior distinct from either grooming or aggressive behavior, and that it may contribute to alopecia in socially housed macaques.

Subgaleal Hematoma at the Contralateral Side of Scalp Trauma in an Adult.

BACKGROUND: Subgaleal hematoma (SGH), an abnormal accumulation of blood under the galeal aponeurosis of the scalp, is more commonly observed in newborns and children. According to previous cases, the etiology of SGH includes mild head trauma, vacuum-assisted vaginal delivery, contusion, and hair braiding or pulling. CASE REPORT: A 39-year-old healthy worker came to our emergency department (ED) due to scalp lacerations from an accident that caused severe twisting of his hair. He denied head contusion and was conscious upon arrival. Physical examination showed three lacerations over his right temporal area. The wounds depth extended to the skull, with a 10-cm subperiosteal pocket beneath the lacerations. Primary sutures were performed immediately under local anesthesia, not only for wound closure but also for hemostasis. However, he returned to our ED 3 h after the first visit for a newly developed soft lump over the left side of his forehead. Computed tomography scan of brain illustrated a huge and diffuse SGH in the left temporal region with extension to periorbital region. Although the option of incision and drainage was discussed with a neurosurgeon and a search for some case reports was done, most of the hematoma could be self-limited. Conservative management with non-elastic bandage packing direct compression was applied. The patient was then admitted for close observation and conservative treatment for 1 week. There was no recurrence of SGH in the following 3 months. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: SGH is an uncommon phenomenon that is caused by tearing of the emissary veins in the loose areolar tissue located beneath the galeal aponeurosis. Conservative treatment with bandage compression is recommended for SGH. Surgery is reserved for cases where non-invasive management fails or severe complications.

IMPAIRED EXECUTIVE FUNCTIONING IN PEDIATRIC TRICHOTILLOMANIA (HAIR PULLING DISORDER).

BACKGROUND: No neurocognitive examinations of pediatric trichotillomania (hair pulling disorder; HPD) have taken place. As a result, science's understanding of the underlying pathophysiology associated with HPD in youths is greatly lacking. The present study seeks to begin to address this gap in the literature via examination of executive functioning in a stimulant-free sample of children with HPD. METHODS: Sixteen and 23 children between 9 and 17 years of age meeting DSM-5 diagnostic criteria for HPD or classified as a healthy control, respectively, were recruited (N = 39) to complete structured interviews, self-reports, and a subset of tests from the Cambridge Automatic Neurocognitive Test Assessment Battery (CANTAB) assessing cognitive flexibility/reversal learning (intradimensional/extradimensional; IED), working memory (spatial span; SSP), and planning and organization (Stocking of Cambridge; SOC). RESULTS: Hierarchical regression analyses indicated that, after controlling for appropriate covariates, diagnostic status predicted impaired performance on both the IED (reversal learning only) and SOC (planning and organization) but failed to predict cognitive flexibility or working memory capacity. Correlational analyses revealed that pulling severity was strongly related to working memory capacity, while disparate relationships between pulling styles (automatic, focused pulling) were evident with respect to working memory and planning and organization. CONCLUSIONS: Children with HPD performed more poorly on tasks of executive functioning as compared to controls. Correlational analyses suggest potentially distinct pathophysiology underlying automatic and focused pulling warranting further research. Limitations and future areas of inquiry are discussed.