Positive sounds during REM with imagery rehearsal therapy helpful against nightmares: Study

"Addition of a well-timed sound during REM sleep augments the effect of image rehearsal therapy (IRT)," the researchers wrote in their study. The study showed that replaying an IRT-associated sound during sleeping with targeted memory reactivation (TMR) boosts the effects of IRT. The study findings, published in the journal Current Biology, could be a promising development for treating people with clinically diagnosed "nightmare disorder."

Nightmare disorder (ND), a sleep condition affecting about 4% of adults, is characterized by dreams with strong negative emotions during REM sleep. Treatments can include counseling, stress reduction, medications, and gradual desensitization. Still, it is mainly treated by imagery rehearsal therapy, where the patients are asked to reimagine the negative storyline of their nightmare into a more positive one. Still, according to the experts, not everyone with nightmare disordered responds to the treatment.

Against the above background, Sophie Schwartz, Swiss Center for Affective Sciences, University of Geneva, Geneva, Switzerland, and colleagues used targeted memory reactivation during REM sleep to strengthen IRT-related memories and speed up ND remission.

For the study, 36 ND patients were asked to conduct an initial session of IRT, and while they created a positive outcome of their nightmare, half of the patients were exposed to a sound (TMR group), while the other group was not exposed to a sound (control group). During the next two weeks, all patients conducted IRT every evening at home and, during REM sleep, were exposed to the sound through a wireless headband, which led to the automatic detection of sleep stages. The primary outcome measure was the frequency of nightmares per week at two weeks.

Following are the study's key points:

• More positive dream emotions and less frequent nightmares were seen in the TMR group compared to the control group after two weeks of IRT and a sustained reduction of nightmares after three months.
• By showing TMR effectiveness during sleep to potentiate therapy, these findings have clinical implications for ND management with relevance to other psychiatric disorders too.

"We here showed a clinical reduction of nightmare frequency in people affected by nightmare disorder under combined IRT and TMR versus patients under IRT alone," the researchers concluded. The study reported an increase in dreams comprising positive emotions in the TMR group only.

"These results suggest that TMR during REM sleep improve IRT outcome by remarkably decreasing nightmares while favoring activation of emotionally positive dreams," they wrote.

Reference:

The study, "Enhancing imagery rehearsal therapy for nightmares with targeted memory reactivation," was published in the journal Current Biology.

DOI: https://doi.org/10.1016/j.cub.2022.09.032