Arousal and Associative Processes in Reinstatement of Fear
- Author(s): Glenn, Daniel Erik
- Advisor(s): Craske, Michelle G
- et al.
This dissertation is a two-paper investigation of the basic associative and arousal-based processes involved in reinstatement of conditional fear. Clarifying the factors involved in reinstatement of fear--a behavioral phenomenon in which the experience of an aversive event following fear extinction produces a return of fear--provides a better understanding of the factors that contribute to the waxing and waning of untreated fear and the return of fear following exposure treatment. Shedding light on the processes involved in reinstatement of fear will contribute to the development of science-based interventions that offset return of fear following fear extinction and improve long term outcomes from exposure therapies for phobias and anxiety disorders.
Study 1 compared the effects of physical pain versus social pain as a reinstating US on reinstatement of conditioned fear, and compared standard reinstatement (same acquisition and reinstatement US) with cross-US reinstatement (different acquisition and reinstatement US). Results indicated that in standard reinstatement procedures social pain produced differential reinstatement of conditional responding, while physical pain produced non-differential reinstatement (i.e., sensitization) in standard and cross-US reinstatement procedures.
Study 2 aimed to replicate the findings from Study 1, and investigated the role of CS+ belongingness on reinstating of fear. Combining data from both studies, the hypothesis was tested that greater physiological arousal experienced during the reinstatement would predict greater post-reinstatement return of conditional responding. Results replicated Study 1 findings, and found that CS+ belongingness may promote differential return of conditional responding in both standard and cross-US reinstatement. Additionally, findings indicated that higher arousal experienced during reinstatement predicts greater non-differential reinstatement, while concordance between arousal experienced during acquisition and reinstatement does not.
In sum, these studies indicate that both social pain and physical pain can reinstate extinguished fear. Social pain promoted differential return of conditional responding (in standard reinstatement) while physical pain elicited a non-differential increase in responding in both standard and cross-US reinstatement. Unforeseen methodological issues may have muddled the findings regarding cross-US reinstatement with qualitatively distinct USs, while providing tentative evidence that individuals under chronic stress might be at elevated risk of an acute stressor triggering a return of fear generalized beyond the original feared stimulus.