Attempts to subtype OCD into phenotypes based on clinical factors that vary across individuals, including age-at-onset, symptom dimension, degree of insight into the rationality of symptoms, comorbid psychiatric conditions, course of illness and response to treatment, have been conducted [22, 26–31]. However, it remains unclear how these different phenotypic subtypes are associated with specific pathophysiological mechanisms or their usefulness in guiding treatment selection [21]. Therefore, in this review we take a different approach to characterizing OCD phenotypes and identifying treatment targets. Specifically, we link variations in the clinical presentation of the disorder (Table 1) to neurocognitive dysfunctions in five neurocircuits that have previously been implicated in OCD (Figure 1, Table 2) [12–14, 16, 32] and discuss how treatments that more specifically target these circuits (Table 3) might benefit patients. Only a few previous attempts have been made to relate alterations in these circuits to particular clinical profiles and treatment approaches [e.g. 11, 33–34]. To our knowledge, no published work has incorporated patients’ subjective reports of their experiences of symptoms or considered specific treatment strategies directed at a range of clinical
