In the last article, we looked at what kind of brainwave entrainment principle monaural beats have. In this article, we will explain in detail how brainwave entrainment makes 'deep sleep', 'way longer'.
One sleep cycle (approximately 90 minutes) consists of the following five phases :1)
This is the stage of < light sleep >. In this stage, your eyes are closed but your eyeballs are still moving slowly. And here, our brain emits theta waves (4-7Hz). This stage accounts for 2 to 5% of total duration of sleep.
Still in the < light sleep >. However, the pattern of brain waves emitted is very different from that of stage 1, which is very important in neuroscience perspective. Along with theta waves explained above, various wavelengths such as fast-wavelength spindles (12-14Hz) and large amplitude k-complexes are observed here. In addition, way less eye movements are observed compared to stage 1. This stage accounts for 45 to 50% of total sleep duration.
This is where < deep sleep > stage begins. The deep sleep stage is also called SWS (Slow-Wave Sleep) because the frequency of the delta (0.5-2 Hz) waves emitted here is relatively lower than other brainwaves. From this stage, no eye movements are observed, and the muscles begin to rest in a relaxed state. This stage accounts for 3 to 8% of total sleep duration.
Another < deep sleep > it is. However, at this stage, more than 50% of all emitted brainwaves are observed as delta waves. During this stage, your body rejuvenates, lowers blood pressure and pulse, boosts metabolism and organizes memories.
This is the < REM sleep>. Here, brainwaves emit beta waves (13-35 Hz) and theta waves (4-67 Hz). As the final stage of sleep cycle, your eyes begin to move rapidly, breathing pattern and pulse become irregular, and autonomic nervous system activity increases.
We sleep as we repeat one sleep cycle several times. Each sleep stage is important, but this article explains the relationship between 'deep sleep' and 'brainwave entrainment', which are closely related to recovery of physical/mental fatigue.
The following study2) claims that binaural beat-induced 'brainwave entrainment' increased the level of 'deep sleep' within a single sleep cycle.
This following experiment succeeded in reducing the ratio of 'sleep stage 2' and significantly increasing the ratio of 'sleep stage 3' through brainwave entrainment using 3Hz binaural beats. 3) The increase in the proportion of the third stage of sleep, that is, deep sleep, also means that the amount of delta waves emitted has increased. The principle is simpler than you think. The frequency of delta waves includes 3Hz. And by providing these binaural beats of 3Hz, we induced delta waves of the same frequency as brainwave entrainment.
As we introduced in the beginning, our body recovers physically and mentally in deep sleep stage. In particular, this stage plays an important role in memory formation and memory strengthening. Thus, you can improve sleep quality and memory at the same time by enhancing deep sleep. The following study proves this. It was reported that cognitive memory ability increased as the proportion of deep sleep in stages 3 and 4 increased. It’s like when taking a nap, you get to experience the feeling of having a clearer mind if you experience deeper sleep.
We understand that there may be people questioning that binaural beat-induced sleep is quite strange. However, according to an integrated analysis of emotions after listening to binaural beats, people who received this stimulation said they did not feel tired at all after waking up. Rather, they stated that they feel energized and clearer after waking up.
Overall, 3Hz binaural beats effectively reduce deep sleep latency, increase deep sleep duration, and reduce light sleep duration. When deep sleep increases, memory improves and the amount of delta waves increases, which also helps the body recover. It is true that continuous research is still needed on how binaural beats will affect our bodies, but what is certain is that they can have a positive effect on sleep by stimulating our brains via brainwave entrainment.