Neural substrates of child irritability in typically developing and psychiatric populations

Abstract

Irritability is an aspect of the negative affectivity domain of temperament, but in severe and dysregulated forms is a symptom of a range of psychopathologies. Better understanding of the neural underpinnings of irritability, outside the context of specific disorders, can help to understand normative variation but also characterize its clinical salience in psychopathology diagnosis. This study assessed brain activation during reward and frustration, domains of behavioral deficits in childhood irritability. Children (age 6-9) presenting in mental health clinics for extreme and impairing irritability (n = 26) were compared to healthy children (n = 28). Using developmentally sensitive methods, neural activation was measured via a negative mood induction paradigm during fMRI scanning. The clinical group displayed more activation of the anterior cingulate and middle frontal gyrus during reward, but less activation during frustration, than healthy comparison children. The opposite pattern was found in the posterior cingulate. Further, in clinical subjects, parent report of irritability was dimensionally related to decreased activation of the anterior cingulate and striatum during frustration. The results of this study indicate neural dysfunction within brain regions related to reward processing, error monitoring, and emotion regulation underlying clinically impairing irritability. Results are discussed in the context of a growing field of neuroimaging research investigating irritable children.

Keywords: Anterior cingulate; Developmental psychopathology; Emotion; Frustration; Irritability; fMRI.

Fig. 1

Left: visual representation of a single losing trial of the FETCH task. Right: visual representation of the end of block online emotion rating. Children were asked to rate their own level of positive/negative feelings after blocks in which they earned nearly enough bones to win their prize or blocks in which they lost all previously earned bones.

Fig. 2

Whole-brain ANOVA revealed a group × condition interaction in the anterior cingulate (ACC)/medial prefrontal cortex and posterior cingulate (ACC).

Fig. 3

Region of interest correlations revealed negative correlations with irritability and activation in the anterior cingulate (ACC) and striatum in the clinical group.