A Sensorimotor-Interoceptive Model for Sensory Phenomena in Obsessive-Compulsive Disorder: Neural and Computational...

Classical models of obsessive-compulsive disorder (OCD) grounded in cognitive-affective processes do not fully account for sensory phenomena (SP), including bodily discomfort, incompleteness, and not-just-right experiences that often precede or accompany compulsive behavior. To address this gap, we propose a sensorimotor-interoceptive model for the sources, generation, and maintenance of SP and SP-driven compulsions in OCD. Specifically, the posterior insula may integrate external sensory signals with internal bodily signals within the perceptual module. These integrated signals are subsequently processed by the salience module centered on the anterior insula and anterior cingulate cortex, where heightened error monitoring may assign excessive salience to integrated signals and recruit the supplementary motor area and primary motor cortex to initiate corrective actions. Dysfunction of a cerebellum-centered forward system may then produce persistent mismatches between predicted and actual action outcomes, which are re-entered into the perceptual module and sustain a recurrent feedback loop. The framework therefore conceptualizes SP-driven compulsions as maladaptive attempts to resolve persistent sensory errors. Predictive coding and active inference provide a computational account of these processes. We underscore that this sensorimotor-interoceptive model, intended to complement existing models, provides an account of symptoms in which SP are prominent and may therefore contribute to a more comprehensive understanding of OCD.