Irritability cuts across many pediatric disorders and is a common presenting complaint in child psychiatry; however, its neural mechanisms remain unclear. One core pathophysiological deficit of irritability is aberrant responses to frustrative nonreward. Here, we conducted a preliminary fMRI study to examine the ability of functional connectivity during frustrative nonreward to predict irritability in a transdiagnostic sample. This study included 69 youths (mean age = 14.55 years) with varying levels of irritability across diagnostic groups: disruptive mood dysregulation disorder (n = 20), attention-deficit/hyperactivity disorder (n = 14), anxiety disorder (n = 12), and controls (n = 23). During fMRI, participants completed a frustrating cognitive flexibility task. Frustration was evoked by manipulating task difficulty such that, on trials requiring cognitive flexibility, “frustration” blocks had a 50% error rate and some rigged feedback, while “nonfrustration” blocks had a 10% error rate. Frustration and nonfrustration blocks were randomly interspersed. Child and parent reports of the affective reactivity index were used as dimensional measures of irritability. Connectome-based predictive modeling, a machine learning approach, with tenfold cross-validation was conducted to identify networks predicting irritability. Connectivity during frustration (but not nonfrustration) blocks predicted child-reported irritability (ρ = 0.24, root mean square error = 2.02, p = 0.03, permutation testing, 1000 iterations, one-tailed). Results were adjusted for age, sex, medications, motion, ADHD, and anxiety symptoms. The predictive networks of irritability were primarily within motor-sensory networks; among motor-sensory, subcortical, and salience networks; and between these networks and frontoparietal and medial frontal networks. This study provides preliminary evidence that individual differences in irritability may be associated with functional connectivity during frustration, a phenotype-relevant state.

Drs. Towbin and Vidal-Ribas contributed equally to this research. Objective: Despite the clinical importance of chronic and severe irritability, there is a paucity of controlled trials for its pharmacological treatment. Here, we examine the effects of adding citalopram (CTP) to methylphenidate (MPH) in the treatment of chronic severe irritability in youth using a double-blind randomized placebo-controlled design. Method: After a lead-in phase of open treatment with stimulant, 53 youth meeting criteria for severe mood dysregulation (SMD) were randomly assigned to receive CTP or placebo (PBO) for 8 weeks. A total of 49 participants, 48 of them (98%) meeting disruptive mood dysregulation disorder (DMDD) criteria, were included in the intent-to-treat analysis. The primary outcome measure was the proportion of response based on improvements of irritability at the week 8 of the trial. Results: At the end of the trial, a significantly higher proportion of response was seen in those participants randomly assigned to CTPþMPH compared to PBOþMPH (35% CTPþMPH versus 6% PBOþMPH; odds ratio ¼ 11.70, 95% CI ¼ 2.00À68.16, p ¼ 0.006). However, there were no differences in functional impairment between groups at the end of the trial. No differences were found in any adverse effect between treatment groups, and no trial participant exhibited hypomanic or manic symptoms. Conclusion: Adjunctive CTP might be efficacious in the treatment of chronic severe irritability in youth resistant to stimulant treatment alone. Clinical trial registration information: A Controlled Trial of Serotonin Reuptake Inhibitors Added to Stimulant Medication in Youth With Severe Mood Dysregulation; https://clinicaltrials.gov; NCT00794040.

Behavioral and neuroimaging evidence suggest that mindfulness exerts its salutary effects by disengaging habitual processes supported by subcortical regions and increasing effortful control processes supported by the frontal lobes. Here we investigated whether individual differences in dispositional mindfulness relate to performance on implicit sequence learning tasks in which optimal learning may in fact be impeded by the engagement of effortful control processes. We report results from two studies where participants completed a widely used questionnaire assessing mindfulness and one of two implicit sequence learning tasks. Learning was quantified using two commonly used measures of sequence learning. In both studies we detected a negative relationship between mindfulness and sequence learning, and the relationship was consistent across both learning measures. Our results, the first to show a negative relationship between mindfulness and implicit sequence learning, suggest that the beneficial effects of mindfulness do not extend to all cognitive functions.

Early engagement in mental health intervention is critical, yet the vast majority of children who are experiencing mental health concerns are not receiving needed services. Pediatric primary care clinics have been recognized as an ideal setting in which to identify and address mental health problems early, although engagement in mental health services within primary care and in community-based settings remains low. Navigators, or individuals with experience in navigating the mental health system, have been highlighted as promising partners in efforts to improve engagement in mental health services. Navigation has a growing body of research support among adults and in targeting medical concerns, but there has been limited research on integrating family navigators into pediatric primary care settings to address mental health concerns. Despite this gap in the evidence base, we believe there is significant promise for the use of this model in addressing children’s mental health needs. In this report, we discuss factors contributing to high levels of unmet mental health needs and low levels of engagement in mental health services, the role that navigators can play in increasing engagement in mental health care, and implications and recommendations related to integrating mental health–focused family navigators into pediatric primary care settings.