Cortisol suppression impairs retrieval of emotional memory and changes its neural correlates immediately and four days post-treatment.

Emotional memories are hard to forget. Yet, past research showed that very high and very low levels of the stress hormone cortisol crucially affect the retrieval of emotional memories both immediately and in a long-lasting manner. With a double-blind, placebo-controlled, within-subject fMRI design involving humans, the present study investigated the acute and lasting effects of cortisol suppression on the neural memory representations for emotional events. The pharmacological suppression of the physiological morning cortisol rise impaired immediate memory retrieval and disrupted the involvement of key brain regions, but also persistently altered the neural memory representations for these emotional memories, tested four days later. These results indicate that cortisol suppression distorts the engagement of the emotional memory neural network and is linked to lasting changes in emotional memory representations, suggesting potential for future research on clinical strategies for attenuating distressing emotional memories.