Have you ever had a dream where you very suddenly realized that you are dreaming and used this information to manipulate your fantasy? This phenomenon is known as lucid dreaming. While reports of lucid dreaming are a fairly common occurrence, there is no real way to determine whether or not when you go to bed at night you will be having a lucid dream. However, a team of German researchers has reportedly found a way to induce lucid dreams in sleeping subjects with the use of transcranial alternating current stimulation (tACS).
27 volunteer subjects were included in the trials to determine whether or not tACS worked to induce lucid dreaming. tACS does not cause any noise or sensation, so the stimulation was applied after the subjects were already sleeping and entering REM sleep, sending electrical currents to the frontal and temporal lobes– the portions of the cerebral cortex associated with self-awareness and meta-cognition. The subjects were then awoken and asked to rate their dreams based on awareness that they were dreaming, vividness, and awareness of the dream plot. Though the subjects chosen for the experiment had never before experienced lucid dreams, many reported having them after tACS. In addition, researchers found that it was only certain frequencies which were able to trigger the lucid dreams– in particular 40 Hz (77 percent of participants reported lucid dreams at this frequency), and 25 Hz (58 percent reported lucid dreams at this frequency).