15.2 Identifying the Mechanisms of Interpretation Bias in Irritability

Objectives

Pathologic irritability, as in disruptive mood dysregulation disorder (DMDD), is associated with a hostile interpretation bias, a tendency to interpret ambiguous social information as threatening. Reductions in irritability and aggression have been associated with training toward more positive interpretations of ambiguous facial expressions (interpretation bias training, IBT). One potential mechanism of IBT is the ability to learn new, positive associations to ambiguous face emotions. An

Methods

IBT is a cognitive retraining that requires trainees to make forced, two-choice (happy/angry) judgments of 15 facial expressions on a linear morph continuum from happy to angry. Trainees receive feedback encouraging them to switch their prior judgments of angry to happy for two ambiguous morphs. We used a computational model based on the Rescorla–Wagner equation to measure learning. Separate learning rates were calculated for predominantly happy and predominantly angry faces in each of

Results

Relative to HV youths, those with DMDD learn more slowly [F(1,21) = 7.1, P = 0.015] and require more sessions to learn new, positive associations to ambiguously angry faces [F(1,58) = 4.61, P = 0.036]. Learning rates did not differ for predominantly happy faces.

Conclusions

Social impairments are known to be present in irritable youths. Thus, these differences may reflect a general impairment in social learning in DMDD. Future studies may establish whether irritability is linked to impairments in learning benign interpretations of ambiguous social information and whether this impairment maintains a hostile interpretation bias.

COG, DMDD, IMD