Background Emotional lability, defined as rapid and/or intense affect fluctuations, is associated with pediatric psychopathology. Although numerous studies have examined labile mood in clinical groups, few studies have used real-time assessments in a well-characterized transdiagnostic sample, and no prior study has included participants with disruptive mood dysregulation disorder (DMDD). The present study leverages ecological momentary assessment (EMA) to assess emotional lability in a transdiagnostic pediatric sample. Methods One hundred thirty participants ages 8-18 with primary diagnoses of DMDD, attention-deficit/hyperactivity disorder (ADHD), an anxiety disorder (ANX), or healthy volunteers completed a previously validated 1-week EMA protocol. Clinicians determined diagnoses based on semi-structured interviews and assessed levels of functional impairment. Participants reported momentary affective states and mood change. Composite scores of fluctuations in positive and negative affect were generated. Affect fluctuations were compared between diagnostic groups and tested for their association with functional impairment. Results Diagnostic groups differed in levels of negative and positive emotional lability. DMDD patients demonstrated the highest level of labile mood compared with other groups. Emotional lability was associated with global impairment in the whole sample. Conclusions Both positive and negative emotional lability is salient in pediatric psychopathology and is associated with functional impairment, particularly in DMDD youth.

Emotional lability, defined as rapid and/or intense affect fluctuations, is associated with pediatric psychopathology. Although numerous studies have examined labile mood in clinical groups, few studies have used real-time assessments in a well-characterized transdiagnostic sample, and no prior study has included participants with disruptive mood dysregulation disorder (DMDD). The present study leverages ecological momentary assessment (EMA) to assess emotional lability in a transdiagnostic pediatric sample. One hundred thirty participants ages 8−18 with primary diagnoses of DMDD, attention-deficit/hyperactivity disorder (ADHD), an anxiety disorder (ANX), or healthy volunteers completed a previously validated 1-week EMA protocol. Clinicians determined diagnoses based on semi-structured interviews and assessed levels of functional impairment. Participants reported momentary affective states and mood change. Composite scores of fluctuations in positive and negative affect were generated. Affect fluctuations were compared between diagnostic groups and tested for their association with functional impairment. Diagnostic groups differed in levels of negative and positive emotional lability. DMDD patients demonstrated the highest level of labile mood compared with other groups. Emotional lability was associated with global impairment in the whole sample. Both positive and negative emotional lability is salient in pediatric psychopathology and is associated with functional impairment, particularly in DMDD youth.

Abstract Irritability is a transdiagnostic symptom dimension in developmental psychopathology, closely related to the Research Domain Criteria (RDoC) construct of frustrative nonreward. Consistent with the RDoC framework and calls for transdiagnostic, developmentally-sensitive assessment methods, we report data from a smartphone-based, naturalistic ecological momentary assessment (EMA) study of irritability. We assessed 109 children and adolescents (Mage = 12.55 years; 75.20% male) encompassing several diagnostic groups – disruptive mood dysregulation disorder (DMDD), attention-deficit/hyperactivity disorder (ADHD), anxiety disorders (ANX), healthy volunteers (HV). The participants rated symptoms three times per day for 1 week. Compliance with the EMA protocol was high. As tested using multilevel modeling, EMA ratings of irritability were strongly and consistently associated with in-clinic, gold-standard measures of irritability. Further, EMA ratings of irritability were significantly related to subjective frustration during a laboratory task eliciting frustrative nonreward. Irritability levels exhibited an expected graduated pattern across diagnostic groups, and the different EMA items measuring irritability were significantly associated with one another within all groups, supporting the transdiagnostic phenomenology of irritability. Additional analyses utilized EMA ratings of anxiety as a comparison with respect to convergent validity and transdiagnostic phenomenology. The results support new measurement tools that can be used in future studies of irritability and frustrative nonreward.

Adolescence is a sensitive period for the development of adaptive social behaviors and social anxiety, possibly due to aspects of brain development. However, research is needed to examine interactions among age, social anxiety, and social dynamics previously shown to influence neural responding. The current functional magnetic resonance imaging (fMRI) study examines brain function in 8-18 year-olds with varying levels of social anxiety. Interactions are examined among age, social anxiety, and two key task factors: valence and predictability of social interactions. Results demonstrate age, social anxiety severity, and each of the two key task-based factors interact to predict neural response in the caudate, middle and superior temporal gyri. In particular, among adolescents less-than 13 years of age, higher social anxiety predicted greater responding to unpredictable negative evaluations. However, in this same age group, the opposite pattern emerged during receipt of unpredictable positive evaluations, with less neural response in more anxious youth. Adolescents aged 13 and older overall showed less robust effects. We discuss these findings in terms of age- and anxiety-related differences in socio-emotional processing.