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Circuit-based mechanisms mediating the development and execution of habitual behaviors involve complex cortical-striatal interactions that have been investigated in animal models and more recently in humans. However, how human brain circuits implicated in habit formation may be perturbed in psychiatric disorders remains unclear. First, we identified the locations of the sensorimotor putamen and associative caudate in the human brain using probabilistic tractography from Human Connectome Project data. We found that multivariate connectivity of the sensorimotor putamen was altered in humans with binge eating disorder and bulimia nervosa and that the degree of alteration correlated with severity of disordered eating behavior. Furthermore, the extent of this circuit aberration correlated with mean diffusivity in the sensorimotor putamen and decreased basal dopamine D2/3 receptor binding potential in the striatum, consistent with previously reported microstructural changes and dopamine signaling mediating habit learning in animal models. Our findings suggest a neural circuit that links habit learning and binge eating behavior in humans, which could, in part, explain the treatment-resistant behavior common to eating disorders and other psychiatric conditions. Habit circuitry alterations in binge eating: It has been proposed that neural habit circuitry may contribute to disordered eating behavior, though this hypothesis remains difficult to test. Wang et al. now report that the connectivity of a striatal brain subregion involved in habit circuitry is altered in individuals with recurrent binge eating. These individuals also showed reduced striatal dopamine D2/3 receptor binding potential and altered putamen gray matter microstructure, further suggesting altered neural habit regulation. An involvement of neural habit circuitry in binge eating behavior could potentially have diagnostic and therapeutic ramifications for patients with this disorder. —CAC [ABSTRACT FROM AUTHOR]