Research paperAltered neural function to happy faces in adolescents with and at risk for depression

- We examine functional connectivity in adolescents with and at risk for mood disorders.
- At-risk adolescents showed elevated DLPFC and lowered ventral putamen activation to cues of social reward.
- Adolescents with MDD showed reduced DLPFC functional connectivity with the VLPFC.
- Elevated DLPFC and lowered ventral striatal activation in at-risk adolescents may be a marker of risk or resiliency.
- Altered DLPFC functional connectivity may be a marker of depressed mood state.

BackgroundThere is accumulating evidence of alterations in neural circuitry underlying the processing of social-affective information in adolescent Major Depressive Disorder (MDD). However the extent to which such alterations are present in youth at risk for mood disorders remains unclear.MethodWhole-brain blood oxygenation level-dependent task responses and functional connectivity using generalized psychophysiological interaction (gPPI) analyses to mild and intense happy face stimuli was examined in 29 adolescents with MDD (MDD; M age, 16.0, S.D. 1.2 years), 38 healthy adolescents at risk of a mood disorder, by virtue of having a parent diagnosed with either Bipolar Disorder (BD) or MDD (Mood-risk; M age 13.4, S.D. 2.5 years) and 43 healthy control adolescents, having parents with no psychiatric disorder (HC; M age 14.6, S.D. 2.2 years).ResultsRelative to HC adolescents, Mood-risk adolescents showed elevated right dorsolateral prefrontal cortex (DLPFC) activation to 100% intensity happy (vs. neutral) faces and concomitant lowered ventral putamen activity to 50% intensity happy (vs. neutral) faces. gPPI analyses revealed that MDD adolescents showed significantly lower right DLPFC functional connectivity with the ventrolateral PFC (VLPFC) compared to HC to all happy faces.LimitationsThe current study is limited by the smaller number of healthy offspring at risk for MDD compared to BD.ConclusionsBecause Mood-risk adolescents were healthy at the time of the scan, elevated DLPFC and lowered ventral striatal activity in Mood-risk adolescents may be associated with risk or resiliency. In contrast, altered DLPFC-VLPFC functional connectivity in MDD adolescents may be associated with depressed mood state. Such alterations may affect social-affective development and progression to a mood disorder in Mood-risk adolescents. Future longitudinal follow-up studies are needed to directly answer this research question.