Trait anxiety and fear generalization: Overgeneralization of fear or undergeneralization of safety learning?

The tendency to overgeneralize fear learning has been identified as a potential risk factor for anxiety disorders. In this study, we examined whether highly anxious individuals differed from low anxious individuals in how they generalized fear (learning when an aversive stimulus is present) and safety (learning when an aversive stimulus is absent) following differential conditioning with an aversive scream outcome. We achieved this by using a morphed shape dimension to separately measure generalization from the fear cue (predicting the scream) and generalization from the safety cue (predicting the absence of the scream). In two experiments, we found that relative to low trait anxious participants, high trait anxious participants showed higher outcome predictions to stimuli resembling the safety cue (i.e., they undergeneralized safety learning), but not for stimuli resembling the fear cue (i.e., they did not overgeneralize fear learning). Undergeneralization was not found when a neutral outcome was used, suggesting that this effect is dependent on the use of an aversive outcome and specific to safety learning. Our findings suggest that safety generalization may vary more as a function of trait anxiety than fear generalization, and therefore future research should separately measure these processes to uncover the mechanisms driving excessive spread of fear.