The brain cycles through four distinct phases: phase 1, 2, 3, 4, which is rapid eye movement (REM) sleep. REM sleep accounts for 25% of the sleep cycle and first occurs 70-90 minutes after falling asleep. Since sleep cycles repeat, REM sleep is entered several times during the night.
When you sleep well, you wake up feeling rested and refreshed. But to achieve this, you must experience each of the stages of sleep. Sleep stages can be divided into two categories: rapid eye movement (REM) and non-rapid eye movement (NREM).
The NREM stage accounts for about 75% of total sleep time and consists of phases of progressively deeper sleep.
· N1 (Stage 1) – The lightest stage of sleep, when you are between asleep and awake.
· N2 (Stage 2) : When you fall into a deep sleep and lose awareness of your surroundings.
· N3 (stages 3 and 4) – The stages of deep, restorative sleep that are considered the most important for your health. During this stage, brain activity experiences slow waves, and you hardly wake up.
Which stage makes you feel rested and energized?
Phase IV (The stage of deep sleep or delta sleep)
The deep sleep stage usually encompasses approximately 20% of the total sleep cycle. It is the most important stage of all, because this is where the quality of rest is determined. During this phase of sleep, waking up is also difficult. Respiratory rate is very low, as well as blood pressure, which usually drops between 10 and 30%.
This stage of sleep is characterized by high brain activity, and this is when dreams appear. It lasts about 10 minutes and usually occurs 90 minutes after falling asleep and every 90 minutes thereafter. The eyes move, but the body is still relaxed.
A night's sleep typically begins with long periods of deep sleep with shorter REM periods. As morning approaches, the REM stage advances as the deep sleep stages subside. This cycle of NREM to REM sleep continues throughout the night, and they work together to relax and recompose the body while you rest. A good night's sleep revitalizes and restores the body. It improves your mood, boosts creativity, regulates hormones and protects against disease. For optimal health, most adults should aim to get 7-9 hours of sleep a night.
During REM sleep, the brain and body are energized and this is when you dream (1). REM sleep is thought to be involved in memory storage and learning and also helps balance mood, although the exact mechanisms are not well understood.
REM sleep is initiated in response to signals sent to and from different regions of the brain. The signals are sent to the cerebral cortex, which is responsible for learning, thinking, and organizing information. Signals are also sent to the spinal cord to stop movement, creating a temporary inability to move the muscles ("paralysis") of the arms and legs (2). An abnormal alteration of this temporary paralysis can cause people to move while dreaming. This type of movement during sleep can cause injuries, for example when a person bumps into a piece of furniture while dreaming of catching a ball (3).
REM sleep stimulates the regions of the brain that are used for learning. Studies have shown that when people are deprived of REM sleep, they fail to remember what they were taught before going to sleep (3). Lack of REM sleep has also been linked to conditions such as migraines (2).
The reason for dreaming during REM sleep is not known. While some of the signals sent to the cerebral cortex during sleep are important for learning and memory, other signals seem to be sent randomly. The cerebral cortex may try to interpret or make sense of these randomly sent signals and create a "story," resulting in dreams.
How Pendulum Helps you Achieve that?
Pendulum is plug and play, based on science, and makes improving sleep engaging by augmenting data insights into pragmatic actions. The science behind it is inspired by a heritage of research, called operant conditioning, and further developed in-house, based on real user data and analytics.
Drowzee has optimized its algorithm for providing NFT and by improving the NFT protocol by refining the duration and frequency of the NFT sessions. The algorithm is the core of the Drowzee SW and its functioning is key to deliver effective NFT. Drowzee has developed this algorithm using a system known as Live Z-score training, which is applied by clinicians in NFT clinics.
Users, can train their brain through the guided sessions using Pendulum to spend less time in phase I and II of their sleep and more in phase III and IV to attain optimal level of rest.
Thus, Drowzee works on the idea that sleeping 8 hours might not always be the answer. Achieving phase III and IV of your sleep cycle and ensuring that a higher percentage of your sleeping time is spent in these two phases is the key to getting a good night sleep.
If you wish to use Pendulum or know someone who is suffering from difficulty falling or staying asleep, you can buy our product here.
1. National Heart, Lung, and Blood Institute (NHLBI) (2009). At-a-glance: Healthy sleep. Retrieved May 30, 2012, from http://www.nhlbi.nih.gov/health/public/sleep/healthy_sleep_atglance.pdf (PDF - 1.81 MB)
2. National Sleep Foundation (NSF) (2010). REM sleep deprivation and migraines. Retrieved June 4, 2012, from http://www.sleepfoundation.org/alert/rem-sleep-deprivation-and-migraine
3. National Institute of Neurological Diseases and Stroke (NINDS) (2007). Dreaming and REM sleep In Brain basics: Understanding sleep. Retrieved May 29, 2012, from https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Understanding-Sleep