Reward Functioning Abnormalities in Adolescents at High Familial Risk for Depressive Disorders

Stress exposure in at-risk, depressed, and suicidal adolescents

BACKGROUND

Stress exposure contributes to the onset, maintenance, and recurrence of major depressive disorder (MDD) in adolescents. However, the precise stress facets (e.g. chronicity, domain) most strongly linked to outcomes at different stages along the depression severity continuum remain unclear. Across two studies, chronic and episodic stressors were comprehensively assessed among: (a) healthy youth with (High-Risk [HR]) and without (Low-Risk [LR]) a maternal history of MDD and (b) adolescents with current MDD and suicide ideation and healthy controls (HC).

METHOD

Study 1 included LR (n = 65) and HR (n = 22) 12- to 14-year-olds (49 females; 56.32%) with no lifetime history of mental disorders. Study 2 enrolled 87 mid-to-late adolescents (64 females; 73.56%), including 57 MDD youth from a short-term intensive treatment service and 30 HCs from the community. All depressed youth reported recent suicide ideation; some had no lifetime history suicide attempts (SI; n = 31) and others reported at least one past year attempt (SA; n = 26). The Life Events and Difficulties Schedule was used to capture stressor severity in both studies.

RESULTS

We used multiple linear regression models that adjusted for demographic and clinical covariates. Being in the HR versus LR group was associated with more severe chronic (β = .22, CI95 = 0.01-0.42, p = .041), independent (β = .34, CI95 = 0.12-0.56, p = .003), and interpersonal (β = .23, CI95 = 0.004-0.45, p = .047) stress severity. By contrast, the MDD group reported significantly more severe chronic (β = .62, CI95 = 0.45-0.79, p < .001) and dependent (β = .41, CI95 = 0.21-0.61, p < .001) stress than the HC group, but not independent (p = .083) stress. Stress severity did not differ between recent attempters versus youth who reported suicide ideation alone (SA vs. SI contrast). However, the SA group reported a higher rate of targeted rejection events (RR = 3.53, CI95 = 1.17-10.70, p = .026).

CONCLUSIONS

Our findings clarify the stressor features that may most strongly contribute to adolescent depression and its clinical correlates at two important points along depression's clinical course.

Targeting positive valence systems function in children of mothers with depressive symptoms: A pilot randomized trial of an RDoC-Informed preventive intervention

Reduced activation of the Research Domain Criteria (RDoC) positive valence systems (PVS) is observed in high-risk (HR) children of depressed mothers and predictive of future psychopathologies. We developed a dyadic, neuroscience-informed preventive intervention, Family Promoting Positive Emotions (FPPE), designed to prevent psychopathology in HR children by targeting PVS processes. We evaluated the initial efficacy of FPPE compared to written information (WI) psychoeducation in engaging PVS-related targets and reducing perceived stress and emotional distress symptoms in HR youth. Participants included 74 children ages 8-12 years and their biological mothers reporting elevated depressive symptoms. Following random assignment, 55 dyads completed FPPE (n = 29) or WI (n = 26) and pre-post assessments of child clinical symptoms. Youth completed a reinforcement learning task and 10 days of positive affect ratings to assess PVS-related targets. Results revealed a small within-subjects increase in child daily positive affect in FPPE, but not WI. Further, FPPE resulted in reductions in mother-reported child perceived stress and symptoms of anger, anxiety, and depression with medium-to-large within-subjects effects. Intervention effects on reinforcement learning and child-rated clinical symptoms were not observed. This study suggests FPPE shows promise in enhancing positive affect and reducing the emergence of clinical symptoms in HR children. CLINICALTRIALS.GOV IDENTIFIER: NCT05223842.

Inverse Association Between Resting-State Putamen Activity and Iowa Gambling Task Performance in Patients With Obsessive-Compulsive Disorder and Control Subjects

BACKGROUND

Symptoms of obsessive-compulsive disorder (OCD) have been conceptualized as manifestations of decision-making deficits. Patients with OCD exhibit impairment during the decision-making process, as assessed by the Iowa Gambling Task (IGT). This impairment is independent of clinical severity and disease progression. However, the association between the decision-making deficit and resting-state brain activity of patients with OCD has not been examined.

METHODS

Fifty unmedicated patients with OCD and 55 matched control subjects completed IGT. Resting-state brain activity was examined using the fractional amplitude of low-frequency fluctuations (fALFFs). fALFF analysis focused on the slow-4 and 5 bands. Group comparisons were performed to determine the association between IGT performance and fALFFs.

RESULTS

There was a significant group difference in the association between the IGT total net score and slow-4 fALFFs in the left putamen (voxel height threshold of p < 0.001; cluster size threshold of p < 0.05; family wise error-corrected). Higher putamen slow-4 fALFFs were correlated with lower IGT scores for OCD patients (r = -0.485; p < 0.0005) and higher IGT scores for control subjects (r = 0.402; p < 0.005). There was no group difference in the association between the IGT total net score and slow-5 fALFFs.

CONCLUSIONS

These findings in unmedicated patients demonstrate the importance of resting-state putamen activity for decision-making deficit associated with OCD, as measured by IGT. The inverse correlation may be explained by the hypersensitive response of the putamen in patients with OCD.

Dissociating default mode network resting state markers of suicide from familial risk factors for depression

Neural signatures of suicide risk likely reflect a combination of specific and non-specific factors, and clarifying specific factors may facilitate development of novel treatments. Previously, we demonstrated an altered pattern of resting state connectivity between the dorsal and ventral posterior cingulate cortex (d/vPCC) and the dorsal anterior cingulate cortex (dACC), as well as altered low frequency oscillations in these regions, in individuals with a history of suicidal thoughts and behaviors (STBs) compared to healthy controls. It remains uncertain, however, whether these markers were directly related to STBs or, more generally, reflect a trait-level risk factor for depression. Here, we examined data from a 3-generational longitudinal study of depression where resting state fMRI data were analyzed from 2nd and 3rd generation offspring of probands with (FH+ = 44: STB+ = 32, STB- = 12) and without (FH- = 25: STB+ = 15, STB- = 10) a family history of major depressive disorder (MDD). Standard seed-based methods and a frequency-based analysis of intrinsic neural activity (ALFF/fALFF) were employed. FH of MDD, but not a personal history of STBs or MDD, was associated with relatively reduced dPCC-dACC, and enhanced vPCC-dACC functional connectivity. FH of MDD showed a pattern of reduced ALFF in the dPCC whereas an STB history was associated with an increase. All findings were invariant to confounding by lifetime MDD and current depression severity. Overall, contrary to predictions, resting state functional connectivity within the default mode network (DMN) was associated with FH of depression rather than STBs. These findings confirm the relevance of DMN functional connectivity for mood disorders and underscore the importance of disambiguating biological factors that differentially relate to mental disorders versus STBs.