Playing a piano chord while sleeping reduced the nightmares.

Using non-invasive methods of manipulating emotions, scientists have been able to reduce the number of nightmares. The study involved 36 volunteers diagnosed with a sleep disorder in the form of nightmares. The researchers asked volunteers to rewrite their most frequent nightmares in a positive light, as well as talk about the sounds they associate with positive emotions. After "rewriting nightmares," the volunteers were put to sleep and played the C6/9 piano chord associated with positive experiences every 10 seconds during REM sleep, when nightmares are most likely. At the beginning of the study, the control group had an average of 2.58 nightmares per week, by the end of the study, the number of nightmares in the control group had decreased to 1.02.