Effects of cortisol on retrieval of extinction memory in individuals with social anxiety

While exposure-based treatment for social anxiety disorder (SAD) has been shown to be effective, the high relapse rate remains a problem. Although relapse has been understood as the inability to retrieve extinction memory, the factors that influence the extent of retrieval of extinction memory have not been determined. This study aimed to examine whether the cortisol response to acute stressors in socially anxious individuals inhibits the retrieval of extinction memory, focusing on the cortisol response to acute stressors as a factor. Thirty-nine participants who scored 42 or more on the Liebowitz Social Anxiety Scale participated in the experiment for two consecutive days. On the first day, a fear conditioning task aimed at learning fear and extinction memory was administered, and on the second day, a psychosocial stress task (Trier Social Stress Test; TSST) was conducted, followed by an extinction retrieval test. The results indicated that cortisol responsiveness (Responder/Non-responder) was not associated with the retrieval of extinction memory indexed by subjective and physiological measures. However, a supplementary analysis revealed that the total amount of cortisol secretion was associated with attenuated retrieval of extinction memory. These findings suggest that the total cortisol secretions, rather than cortisol responsiveness to the acute stressor, may play a role in relapse.