RESULTS: While it didn’t cause them to experience more deep sleep cycles, the pink noise appeared to prolong deep sleep and to increase the size of the subject’s brain waves during that period, as evinced by their EEGs.

The slow brain waves that characterize deep sleep are implicated in information processing and memory formation, and sure enough, on the mornings after those brain waves appeared to have been enhanced […]

IMPLICATIONS: Sound stimulation has been tried before, unsuccessfully. The key here, write the researchers, is that the frequency of the sounds was in sync with the subjects’ brain waves. Were this technique to be further developed, it could potentially be used to improve sleep in general, and possibly even to enhance brain activity when we’re awake. Although it’s even less viable, for now, than electric brain stimulation, the latter has been proposed as a way of treating Alzheimer’s, fighting depression, easing pain, and the ever-popular “boosting creativity.”