18 Nov 2015: A Trans-Diagnostic Approach to Understanding Compulsive Behavior

Claire Gillan
Sir Henry Wellcome post-doctoral fellow
NYU and University of Cambridge
Prominent theories suggest that compulsive behaviors characteristic of obsessive-compulsive disorder (OCD) and addiction are driven by shared deficits in goal-directed control, which confers vulnerability for developing rigid habits. However, recent work has shown that these deficits extend far beyond these archetypal compulsive disorders, casting doubt over the specificity of this effect to disorders of compulsivity. This lack of specificity is unfortunately ubiquitous in psychiatry research, a result, we would argue, of the fact that psychiatric diagnostic categories do not reflect the most discrete and neurobiologically informative phenomena. We investigated if the link between clinical phenotype and goal-directed deficits could be more precisely delineated from a trans-diagnostic perspective. Using a novel, data-driven approach comprising large-scale online testing of variation in psychiatric symptoms and neurocognitive performance in two independent samples, we found evidence that compulsivity is a trans-diagnostic trait, predictive of individual differences in goal-directed deficits. These data showcase a powerful new methodology and highlight the potential of a dimensional, biologically grounded approach to psychiatry research.