TRICHOTILLOMANIA AND SKIN-PICKING DISORDER: NEUROBIOLOGICAL CORRELATES AND TREATMENT OUTCOMES
DOI:
https://doi.org/10.56238/levv16n54-054Keywords:
Trichotillomania, Skin Diseases, Obsessive-Compulsive Disorder, Cognitive Behavioral TherapyAbstract
Introduction: Trichotillomania and skin-picking disorder are chronic body-focused repetitive behaviors that result in significant psychological distress and physical harm. Both conditions are classified under obsessive-compulsive and related disorders, sharing neurobiological mechanisms involving cortico-striatal-thalamo-cortical circuitry dysregulation. Despite advances in understanding these disorders, their underlying pathophysiology and optimal treatment strategies remain incompletely elucidated.
Objective: The main objective of this review was to systematically evaluate the neurobiological correlates and treatment outcomes in patients with trichotillomania and skin-picking disorder. Secondary objectives included: (1) examining the role of functional and structural neuroimaging in elucidating neural abnormalities; (2) assessing pharmacological interventions, including glutamatergic and serotonergic agents; (3) evaluating the efficacy of cognitive-behavioral therapies and habit reversal training; (4) comparing outcomes across combined therapeutic modalities; and (5) identifying gaps in the literature to guide future research.
Methods: A systematic search was performed in PubMed, Scopus, Web of Science, Cochrane Library, LILACS, ClinicalTrials.gov, and the WHO ICTRP registry for studies published between January 2015 and December 2025. Eligible studies included randomized controlled trials, cohort studies, case-control designs, and neuroimaging research involving human participants diagnosed with trichotillomania or skin-picking disorder. Animal and in vitro studies were included separately when relevant. Risk of bias was assessed using RoB 2 and ROBINS-I tools, and evidence certainty was appraised through the GRADE framework.
Results and Discussion: Twenty-three studies met inclusion criteria, encompassing neuroimaging analyses, pharmacological trials, and behavioral therapy evaluations. Neurobiological findings consistently implicated hyperactivity in the anterior cingulate cortex, insula, and basal ganglia regions, while pharmacological interventions such as N-acetylcysteine and SSRIs showed variable efficacy. Cognitive-behavioral interventions, particularly habit reversal therapy, demonstrated the most consistent improvement across studies. Multimodal treatment approaches appeared to yield superior outcomes.
Conclusion: Trichotillomania and skin-picking disorder exhibit shared neural dysregulation within inhibitory control circuits, supporting their conceptualization as related compulsive spectrum disorders. Behavioral therapy remains the cornerstone of treatment, though adjunctive pharmacological strategies may enhance outcomes in selected cases. Continued research integrating neuroimaging and longitudinal follow-up is essential to refine individualized, mechanism-based interventions.
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