Emerging ecophenotype: reward anticipation is linked to high-risk behaviours after sexual abuse

Abstract

Adolescents frequently engage in high-risk behaviours (HRB) following childhood sexual abuse (CSA). Aberrant reward processes are implicated in HRB, and their underlying fronto-striatal networks are vulnerable to neurodevelopmental changes during adversity representing a promising candidate for understanding links between CSA and HRB. We examined whether fronto-striatal responses during reward anticipation and feedback (i) are altered in depressed adolescents with CSA compared to depressed, non-abused peers and (ii) moderate the relationship between CSA and HRB irrespective of depression. Forty-eight female adolescents {14 with CSA and depression [CSA + major depressive disorder (MDD)]; 17 with MDD but no CSA (MDD); 17 healthy, non-abused controls} completed a monetary reward task during functional magnetic resonance imaging. No differences in fronto-striatal response to reward emerged between CSA + MDD and MDD. Critically, high left nucleus accumbens activation during reward anticipation was associated with greater HRB in CSA + MDD compared to MDD and controls. Low left putamen activation during reward feedback was associated with the absence of HRB in CSA + MDD compared to MDD. Striatal reward responses appear to play a key role in HRB for adolescents with CSA irrespective of depression, providing initial support for a CSA ecophenotype. Such information is pivotal to identify at-risk youth and prevent HRB in adolescents after CSA.

Keywords: adolescence; fMRI; high-risk behaviour; reward; sexual abuse.

Fig. 1.

Interaction graphs for reward anticipation. Higher striatal activation in clinical groups predicted greater HRB compared to controls. Higher left NAcc activation predicted greater HRB in depressed adolescents with CSA compared to non-abused peers matched for depression.

Fig. 2.

Interaction graphs for reward feedback. Higher activation in left putamen during reward feedback predicted greater HRB in clinical groups compared to controls. Lower left putamen activation in depressed adolescents with CSA predicted absence of HRB compared to non-abused peers matched for depression.