Abstract:

Patients with major depressive disorder commonly exhibit varying degrees of social dysfunction, whose pathological mechanisms may be closely associated with abnormalities in the social reward system.In recent years, research on social reward circuitry has shifted from a focus on localized functional deficits to a systematic perspective of dysregulation across multiple brain regions. Using multimodal neuroimaging and computational modeling approaches, researchers have begun to explore the dynamic interaction patterns between large-scale brain networks and reward circuitry across the three phases of anticipation, consumption, and learning, as well as emerging topics such as circuit-targeted neuromodulation.This review systematically summarizes the functional abnormalities in the social reward circuitry of patients with major depressive disorder, exploring the potential dual mechanisms involving localized functional impairments of key brain regions and network-level dysregulation across three distinct phases of reward processing: anticipation, consumption, and learning, and elaborates the dynamic manifestation of a dual-mechanism model of local brain region functional impairment-network coordination dysregulation during these phases. The review may provide theoretical foundations for understanding the neural substrates underlying social dysfunction in depression and for optimizing clinical treatment strategies, such as precise neuromodulation targeting specific phases or specific circuits.

Key words: depressive disorder, social reward, neural mechanism, functional impairments of local brain regions, dysregulation of brain networks