Everyone would like to get a full night’s sleep, but the fact is that many of us do not have the seven to nine hours necessary to feel fully rested. For some the problem is the pressure of extra work, while others have trouble falling asleep. And certain jobs make rest difficult to find, as with firefighters, emergency doctors and members of the military. For these persons, recent study on the power of slow waves in the brain, and how to induce these waves in sleeping individuals, may prove very helpful.
What are Slow Waves?
The brain relies heavily on the natural electrical impulses that govern nerve activity. These impulses create wave-like patterns that can be measured with sensitive instruments. Of special importance to getting a “good night’s sleep” are slow waves, generated during phases each night when we are not dreaming (called NREM). At the beginning of a sleep period, the slow waves are frequent and large. As a sleep period extends, our brain creates fewer slow waves and they start to get smaller. If our sleep is interrupted, and the slow waves never get the opportunity to diminish or shrink in amplitude, we do not get the benefits that come from “getting enough sleep.”
Improving Slow Waves
Although pharmaceuticals can increase the number of slow waves and thus shorten the necessary time to feel satisfied after sleep, drugs are generally difficult to flush from our body. If you need to unexpectedly wake and be alert immediately, the presence of sleep chemicals in your system could be a huge disadvantage. Therefore, researchers examined other methods for improving slow wave production, including the use of sound.
Sleep experiments with auditory stimuli have been conducted since the 1940’s. As a result, we know that sound can affect certain events during the sleep cycle. (And not just by waking you up!) Therefore, the study scientists selected sound frequencies known to affect brain waves. Then they monitored their subject’s sleep patterns, looking for slow waves during NREM sleep. When slow waves were absent, they attempted to induce them by playing short tones (only 50 milliseconds in length) that were previously calibrated for each subject to be loud enough to hear when awake, but soft enough to let them sleep. To the benefit of the patients, the auditory tones did create additional slow waves during NREM periods, especially as the night continued. Inducing these additional slow waves improved both the subject’s perception of their sleep quality and their performance on various tasks.
The suggested benefit behind this finding is that people who know their rest period will be shorter than desired, or who expect to be awakened at inopportune times, can improve the quality of their sleep with brain wave monitoring and appropriate auditory stimuli. If you would like to explore these findings with the help of the Sacramento Brain Health Clinic, contact us online or at the number given above.