Functional dysconnectivity in reward-related circuits in adolescents with major depressive disorder with and without suicidal ideation

OBJECTIVE: Adult major depression (MDD) studies implicate reward- and control-network dysconnectivity in suicidality, but it is unclear whether analogous alterations characterize adolescents, whose neural systems are still maturing. METHODS: Resting-state fMRI was obtained from 102 adolescents (12-17 years): 21 MDD with suicidal ideation (SI), 33 MDD without SI, and 48 matched healthy controls. Seed-based analyses targeted bilateral nucleus accumbens (NAc), ventral tegmental area (VTA), and bilateral dorsolateral prefrontal cortex (DLPFC). RESULTS: Between-group effects were specific to NAc circuitry. Adolescents with SI showed reduced coupling of the left NAc with the left superior parietal lobule (BA7) versus controls, and diminished connectivity between the right NAc and right frontal pole (BA47) versus depressed peers without SI. No significant differences emerged for DLPFC- or VTA-seeded connectivity. CONCLUSIONS: The identified functional dysconnectivities in reward-related circuits, particularly the FCs between the NAc and both the frontal pole and superior parietal lobule, may be implicated in the manifestation of suicidality among adolescents with MD. However, the lack of significant associations for DLPFC- and VTA-seeded FC in adolescent MDSI requires further elucidation.