Striatal abnormalities in trichotillomania: a multi-site MRI analysis

Area of Science:

• Neuroscience
• Psychiatry
• Radiology

Background:

• Trichotillomania, a hair-pulling disorder, is classified under Obsessive-Compulsive Related Disorders.
• Previous research suggested striatal abnormalities in trichotillomania models, but direct evidence was limited.

Purpose of the Study:

• To investigate subcortical morphometric abnormalities, including localized shape changes, in adults with trichotillomania.
• To provide direct evidence of structural brain differences in trichotillomania.

Main Methods:

• A pooled analysis of de-identified MRI scans from adult trichotillomania patients and healthy controls.
• Utilized t-tests for volumetric analysis and permutation testing for localized shape quantification.
• Included 68 individuals with trichotillomania and 41 controls, matched for age, gender, and education.

Main Results:

• Significant volumetric reductions observed in the right amygdala and left putamen in patients with trichotillomania.
• Localized shape deformities identified in the bilateral nucleus accumbens, bilateral amygdala, right caudate, and right putamen.
• These subcortical abnormalities are linked to affect regulation, inhibitory control, and habit generation.

Conclusions:

• Structural abnormalities in key subcortical regions are integral to the pathophysiology of trichotillomania.
• Trichotillomania may serve as a valuable model for understanding other compulsive behaviors.
• Findings may explain the efficacy of medications targeting subcortical dopamine and glutamatergic systems.