A recent study published in Current Biology01477-4) provides evidence that people suffering from nightmare disorder can experience an acceleration in the remission of their symptoms when treated with behavioral therapy and Targeted Memory Reactivation.
Nightmare disorder (ND) is a condition characterized by recurrent nightmares that significantly affect daytime functioning. Imagery Rehearsal Therapy (IRT) is the most recommended treatment for ND, whereby patients imagine a more positive outcome for their nightmare, and then recall the new dream. However, “approximately 30% of patients are unresponsive to this treatment,” the authors of the new study explained.
A growing body of evidence indicates that Rapid Eye Movement (REM) sleep can aid in decreasing negative emotions and consolidating the recall of positive emotional memories. With this in mind, the authors sought to investigate whether manipulating memory processing during REM could accelerate the remission of ND when combined with Imagery Rehearsal Therapy.
To this end, they employed Targeted Memory Reactivation (TMR), a widely used procedure for studying memory reactivation mechanisms. In a typical TMR experiment, a tone or an odor previously associated with a chosen task during awake learning is represented during sleep. Reactivated memories are typically better remembered than those not reactivated, suggesting that memory reactivation during sleep can enhance memory consolidation.
“There is a relationship between the types of emotions experienced in dreams and our emotional well-being,” explained senior author Lampros Perogamvros, a psychiatrist at the Sleep Laboratory of the Geneva University Hospitals and the University of Geneva.
“Based on this observation, we had the idea that we could help people by manipulating emotions in their dreams. In this study, we show that we can reduce the number of emotionally very strong and very negative dreams in patients suffering from nightmares.”
Thirty-six patients with ND received an initial session of IRT in which while imagining a positive ending to their nightmare, half of the patients received a sound (TMR group), while the other half did not (control group). During the following two weeks, all patients rehearsed the positive dream scenario before sleep. Additionally, they wore a sleep headband device at home that delivered the sound during REM sleep and filled in a dream diary every morning. At the end of the two weeks and after three months, nightmare intensity and frequency were evaluated.
By combining IRT with TMR, the study showed a clinical reduction in nightmare frequency compared to using IRT alone. The TMR group also exhibited a significant increase in positive emotional dreams compared to the control group. These findings can potentially lead to innovative approaches for promoting emotional well-being.
“We were positively surprised by how well the participants respected and tolerated the study procedures, for example performing imagery rehearsal therapy every day and wearing the sleep headband during the night,” Perogamvros said in a news release. “We observed a fast decrease of nightmares, together with dreams becoming emotionally more positive. For us, researchers and clinicians, these findings are very promising both for the study of emotional processing during sleep and for the development of new therapies.”
Despite this, there are limitations to note. For example, the study did not include a group of patients without stimulation, and it did not assess other possible effects of the sound stimulation since polysomnography was not recorded. Future research could take these limitations into account.
The study, “Enhancing imagery rehearsal therapy for nightmares with targeted memory reactivation“, was authored by Sophie Schwartz, Alice Clerget, and Lampros Perogamvros.
