Preschool- and School-Age Irritability Predict Reward-Related Brain Function

Area of Science:

• Neuroscience
• Developmental Psychology
• Child Psychiatry

Background:

• Chronic irritability in childhood is common, impactful, and predicts future maladjustment.
• The underlying brain mechanisms (pathophysiology) of childhood irritability are not well understood.
• Altered reward processing is a potential contributing factor to irritability.

Purpose of the Study:

• To investigate the relationship between the developmental timing of irritability (preschool vs. school-age) and reward-related brain function.
• To identify specific neural connectivity patterns associated with irritability at different developmental stages.

Main Methods:

• Longitudinal assessment of children's irritability at preschool and school-age using clinical interviews.
• Functional magnetic resonance imaging (fMRI) during a monetary incentive delay task in school-aged children (N=46).
• Analysis of reward-related brain connectivity, comparing children with higher vs. lower irritability.

Main Results:

• Preschool irritability (controlled for concurrent irritability) was linked to altered connectivity between the right amygdala and insula/inferior parietal lobe, and the left ventral striatum and several parietal/occipital regions.
• Concurrent irritability (controlled for preschool irritability) showed altered connectivity between amygdalae and the superior frontal gyrus, and the left ventral striatum and precuneus/culmen.
• Neural differences were most pronounced when comparing reward vs. no-reward conditions during missed targets.

Conclusions:

• Both preschool-age and concurrent irritability are uniquely associated with aberrant reward-related neural connectivity.
• The developmental timing of irritability is crucial for understanding its impact on brain function.
• These findings highlight specific neural pathways involved in the pathophysiology of childhood irritability.