Scientists may have found a way to cause lucid dreams—those experiences in which we know we're dreaming and can, in some cases, control the dream. The key, explains an expert, is electric scalp stimulation. "I never thought this would work," Harvard researcher Dr. John Allan Hobson tells LiveScience. "But it looks like it does." Researchers already knew that lucid dreamers exhibit a boost in brain activity in the frontal and temporal lobes comparable to being awake.
In a study, they applied a variety of currents to the scalps of volunteers in REM sleep. Stimulation at certain frequencies—specifically, 40 Hz and 25 Hz—prompted increased activity in the frontal and temporal lobes, the Guardian reports. Some 77% of participants stimulated with 40-Hz currents reported lucid dreams. The study offers "a step in the direction of understanding how the brain manages to hallucinate and be deluded," says a researcher. It could also be beneficial in treating nightmares, the team says.