Parsing dimensional vs diagnostic category-related patterns of reward circuitry function in behaviorally and emotionally dysregulated youth in the Longitudinal Assessment of Manic Symptoms study

Abstract

Importance: Pediatric disorders characterized by behavioral and emotional dysregulation pose diagnostic and treatment challenges because of high comorbidity, suggesting that they may be better conceptualized dimensionally rather than categorically. Identifying neuroimaging measures associated with behavioral and emotional dysregulation in youth may inform understanding of underlying dimensional vs disorder-specific pathophysiologic features.

Objective: To identify, in a large cohort of behaviorally and emotionally dysregulated youth, neuroimaging measures that (1) are associated with behavioral and emotional dysregulation pathologic dimensions (behavioral and emotional dysregulation measured with the Parent General Behavior Inventory 10-Item Mania Scale [PGBI-10M], mania, depression, and anxiety) or (2) differentiate diagnostic categories (bipolar spectrum disorders, attention-deficit/hyperactivity disorder, anxiety, and disruptive behavior disorders).

Design, setting, and participants: A multisite neuroimaging study was conducted from February 1, 2011, to April 15, 2012, at 3 academic medical centers: University Hospitals Case Medical Center, Cincinnati Children's Hospital Medical Center, and University of Pittsburgh Medical Center. Participants included a referred sample of behaviorally and emotionally dysregulated youth from the Longitudinal Assessment of Manic Symptoms (LAMS) study (n = 85) and healthy youth (n = 20).

Main outcomes and measures: Region-of-interest analyses examined relationships among prefrontal-ventral striatal reward circuitry during a reward paradigm (win, loss, and control conditions), symptom dimensions, and diagnostic categories.

Results: Regardless of diagnosis, higher PGBI-10M scores were associated with greater left middle prefrontal cortical activity (r = 0.28) and anxiety with greater right dorsal anterior cingulate cortical (r = 0.27) activity to win. The 20 highest (t = 2.75) and 20 lowest (t = 2.42) PGBI-10M-scoring youth showed significantly greater left middle prefrontal cortical activity to win compared with 20 healthy youth. Disruptive behavior disorders were associated with lower left ventrolateral prefrontal cortex activity to win (t = 2.68) (all P < .05, corrected).

Conclusions and relevance: Greater PGBI-10M-related left middle prefrontal cortical activity and anxiety-related right dorsal anterior cingulate cortical activity to win may reflect heightened reward sensitivity and greater attention to reward in behaviorally and emotionally dysregulated youth regardless of diagnosis. Reduced left ventrolateral prefrontal cortex activity to win may reflect reward insensitivity in youth with disruptive behavior disorders. Despite a distinct reward-related neurophysiologic feature in disruptive behavior disorders, findings generally support a dimensional approach to studying neural mechanisms in behaviorally and emotionally dysregulated youth.

Figure 1

Reward task adapted from(40). Participants guessed whether a card(value: 1–9) was higher/lower than 5, then viewed the number, outcome(Win=green arrow, Loss=red arrow), and fixation cross. Control trials: Participants pressed a button to “X”, then viewed an asterisk, circle, and fixation cross.

Figure 2

Entire bilateral ROI mask analysis to Win>control in LAMS youth (n=85) (A)Left mPFC, bilateral dACC, and bilateral VLPFC activity (orange) (B)Left mPFC activity and PGBI-10M(teal)(r=.28) (C)Overlap between left mPFC activity in (A) and (B). (D)Bilateral dACC activity and SCARED (purple) (r=.27). (E)Overlap between dACC activity in (A) and (D).

Figure 3

Group contrast of Win>control activity in left mPFCclusters determined in analyses depicted in Figure 2(A). Relative to healthy youth (n=20) (black) LAMS youth with high PGBI-10M scores (n=20) (red) and LAMS youth with low PGBI-10M scores (n=20) (blue) had greater left mPFC activity.