Ventral Striatum Functional Connectivity during Rewards and Losses and Symptomatology in Depressed Patients

Abstract

BACKGROUND The ventral striatum (VS) and striatal network supports goal motivated behavior. Identifying how depressed patients differ in their striatal network during the processing of emotionally salient events is a step towards uncovering biomarkers for diagnosis and treatment. METHODS 38 depressed and 30 healthy adults completed a task that examined brain activation to the anticipation and receipt of monetary rewards and losses. Data were collected using a 3T Siemens Trio scanner. Functional connectivity differences were examined with seeds in the Left or Right VS. FC estimates were regressed on specific symptoms. RESULTS Depressed patients displayed higher functional connectivity between the VS and midline cortical areas during loss versus reward trials. Anhedonia and depressed mood were associated to fairly similar striatal circuits but suicidality was associated to a unique VS-midline structures coupling, while depression severity was linked to higher VS to caudate and precuneus connectivity during loss versus reward trials. CONCLUSIONS Depression is characterized by excessive VS coupling to cognitive control and associative networks during losses versus rewards. High VS to midline cortical structures coupling may index suicidality.

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