The research of the Psychiatric NeuroCognition Lab (“PNCLab”) uses a multi-method approach to investigating the pathophysiology of psychiatric disorders, focusing on heterogeneity in obsessive-compulsive disorder (OCD) and transdiagnostic features shared with other disorders. The lab’s work seeks to understand the fundamental problem of variability of treatment efficacy among patients with the same diagnosis by employing a program of research to: 1) identify behavioral and neural mechanisms underlying core processes contributing to within-disorder heterogeneity and 2) target those mechanisms using methods to manipulate neural circuit functioning in order to alter behavior and, ultimately, psychopathological symptoms. The majority of the lab’s work has focused on identifying and targeting mechanisms underlying sensory processing abnormalities in OCD. Clinically, sensory symptoms in OCD manifest as aversive sensations that drive compulsions instead of fear (collectively referred to as “sensory phenomena” and including sensory-based urges and “not-just-right” experiences). Sensory phenomena are prevalent in over half of individuals with OCD, where they cause significant distress and functional impairment, yet are not well addressed by standard treatment approaches. Research in the lab has found that sensory phenomena in OCD are associated with alterations of interoception (the detection and integration of sensations from within the body) and the hyper-functioning of neural circuits involving the insula, sensorimotor regions, and orbitofrontal cortex. Current projects test the use of pharmacological (high-dose ondansetron) and neuromodulatory (TMS) manipulations to inhibit the functioning of the insula and sensorimotor cortical areas in order to decrease the severity of sensory phenomena. Although the lab’s core research focus is on OCD, an overarching goal is to test whether these mechanisms are specific to OCD or exist across disorders. Additional areas of research in the lab investigate interoception and sensory symptoms in major depression and autism spectrum disorder, as well as other transdiagnostic processes such as perseverative cognition. The overall aim of this work is to use mechanistic findings to develop and refine treatments targeting individual behavioral and neural characteristics within the framework of a personalized medicine approach.