The Science of Sleep - FRENZ™ by Earable® Neuroscience

The Science of Sleep

January 16, 2023 | Tags: science

The FRENZ Brainband is the world's first hospital-grade brain-tracking wearable that precisely measures and stimulates brain activity via bone-conduction speakers with clinical precision. FRENZ doesn't just track; it lets you fall asleep faster and deeper, finds your sharper focus, improves your overall mental health, and unlocks your brain's true potential. 

But why is it so important? Everyone understands that most people require 7-9 hours of sleep daily. But why do we need to sleep, and what happens if we don't get enough?

During sleep, our bodies are mended and rebuilt. Furthermore, sleep aids in the removal of debris from the lymphatic system, which strengthens the immune system. Many critical processes occur during our sleep:

  • Muscle healing

  • Protein synthesis

  • Tissue growth

  • Hormone release

Other advantages of sleep include stress reduction, cognitive enhancement, healthy body weight maintenance, illness prevention, and much more.

As a result, getting enough sleep is essential for our health. Most individuals need at least 7 hours of sleep every day, and sleep loss is associated with a number of risks and severe conditions. Sleep deprivation, for example, has been demonstrated in research to leave people subject to attention lapses, impaired cognition, delayed reactions, and mood swings.

Sleep has many critical components, and the FRENZ Brainband can help.

Sleep Stages

Sleep, according to neuroscience, can be classified into four stages of sleep cycles. The first three stages are referred to as non-rapid eye movement (NREM), whereas the final step is referred to as rapid eye movement (RREM or REM). Using heart rate and SpO2 sensors, most sleep trackers can only estimate sleep stages. Despite recent advances, sensors are unable to track stages precisely. The sleep stage determined by these gadgets is purely speculative. There is no place for assumptions in science. Brainwave measurements are the sole permitted tracking approach in the sleep lab.

Light sleep is defined as stages 1 and 2, whereas deep sleep is defined as stage 3. When your muscles begin to relax, and your breathing rate, heart rate, and body temperature begin to decrease, you are in the light sleep stage. After a long day, your body heals and recovers during the deep sleep stage. Deep sleep is necessary for both mental and physical recovery. Finally, REM is typically when you dream. Your pulse, breathing rate, and blood pressure all rise when your brain activity rises:

This first stage of NREM sleep is characterized by light sleep and reflects the transition from wakefulness to sleep. Muscles relax, and your heart rate, respiration, eye movements, and brain waves, which are more active when you awake, start to slow down. Stage 1 often lasts several minutes.

Stage 2 NREM (Light Sleep): During this second NREM slumber stage, the heart and breathing rates continue to slow, and the muscles relax. Your body temperature will drop, and your eye motions will halt. In addition to transient bursts of higher-frequency electrical activity, brain waves remain slow. Stage 2 is usually the longest of the four sleep stages. 

This non-REM (deep sleep) stage leaves you feeling refreshed and alert the next day. Heart rate, breathing, and brain wave activity are at their lowest, yet muscle tension is at its highest.

NREM (Deep Sleep) Stage 3: This stage is critical for waking up refreshed and attentive. Heart rate, breathing, and brain wave activity all fall to their lowest levels, while muscle tension peaks. This phase will last longer at first and then progressively fade away throughout the night.

The first REM stage begins about 90 minutes after falling asleep. As the name implies, your eyes will move quickly back and forth beneath your eyelids. Respiration, heart rate, and blood pressure will all increase. REM sleep causes paralysis of your arms and legs, which is thought to prevent you from physically acting out your dreams. Each REM sleep cycle increases longer as the night continues. Numerous studies have also linked REM sleep to memory consolidation, or the conversion of novel experiences into long-term memories. The duration of REM sleep decreases with age, causing you to spend more time in NREM sleep.

How the FRENZ Brainband tracks the four sleep stages

You might wonder why, if scientists already know about brainwaves and if they have several clinical devices that help them track our brain stage, track our emotions, and our status, why neurosciences are way below other sciences in understanding human capabilities.

There are several reasons for that; one of the most important ones is the lack of affordable devices that can track our brainwaves comfortably & precisely. Most devices that are used to track our status are professional PSG devices, which might cost about $100k, are as big as an old fashion desktop computer, require several strings attached to our skin, and require professional technicians to operate manually. And you know what? Each extremely uncomfortable night in those sleep labs costs about $1500-2000. In Vietnam, there are only 50 facilities that have PSG machines for sleep treatment, and they are always in full. 

This is why FRENZ was created to solve the barriers that block consumers from getting a better sleep-supporting device:

  • Precision

  • Comfort

  • Effectiveness

  • Accessibility

Invented by scientists and engineers from the University of Oxford University, the University of Colorado, and Earable®Neuroscience, after hundreds of iterations spanning eight years, FRENZ was engineered to solve three major challenges to bringing clinical neuroscience into practical daily usage:

  1. Precision: The mechanical engineering team and electrical-circuit experts engineered a proprietary low-noise electrical integrated system that captures signals precisely, eliminating noise caused by the wearer's movements. FRENZ applies patented ML algorithms to filter, split, and process multiple signal channels to activate appropriate acoustic stimulation at precise moments. Frenz’s tracking result is comparable to professional PSG devices, which can cost $100k and require a special technician to operate, which also raise operation cost to $1500-2000 per night. Besides, requiring technicians to operate stimulation is mostly impossible. 

  1. Comfort: If you ever join a sleep lab session using PSG devices to track sleep, you will know that these machines contact us using several wires, which is extremely uncomfortable. There is no way a normal person can use those devices daily. Using advanced nanomaterial science, FRENZ is designed for comfortable daily and nightly wear. In addition, FRENZ integrates behind-the-ear bone-conduction speakers inside innovative sound chambers to withstand head pressure and avoid sound distortion. The device's over-ear dry-sensing electrodes (FrenzTouch™) are strategically placed at optimal locations to track and reference strong signal sources amidst noises. FrenzTouch™, made of a proprietary perfect-ratio mixture of nanomaterials, including carbon nanotubes, silver nanowires, and conductive silicon, under a special curing process, has flawless conduction while maintaining comfort in any sleeping position.

  1. Effectiveness: Besides monitoring, FRENZ administers ongoing personalized clinically-proven cognitive behavioral therapies. After rigorous clinical trials involving 1,250 subjects, FRENZ has proven effective in reducing average sleep onset by 19 minutes.

  1. Accessibility: In addition to rampant sleep deprivation and conditions, many people cannot access in-lab polysomnography, leaving potentially serious conditions undiagnosed. FRENZ is the only product to deliver clinical-grade sleep support straight to the user, making mental health accessible to everyone at a reasonable price. With FRENZ, customers can self-administer clinical-grade polysomnography tests and personalized cognitive behavioral therapy in the comfort of their own homes, often for less than the cost of one sleep clinic treatment. FRENZ makes the sleep clinic accessible to everyone.

How FRENZ helps you fall asleep faster

Many people experience Signiant trouble falling asleep quickly. FRENZ provides clinically proven therapies such as cognitive behavioral therapy (CBT), breathing coaching, white noise, and pink noise to help users fall asleep faster.

Cognitive Behavioral Therapy: CBT has evolved as a major clinical psychological treatment that is helpful for various mental health difficulties, including insomnia and other sleep disorders. It is a widely accepted and successful methodology for improving sleep quality and overcoming sleep circumstances. When used to treat sleep disorders, CBT employs various techniques, including breathing exercises, autogenic training, and hypnotic cues, to assist patients in recognizing and substituting thoughts and behaviors that trigger or worsen sleep disorders with habits that promote better sleep. Furthermore, unlike prescription drugs, CBT helps people address the underlying causes of their sleep disorders, resulting in long-term results.

Breathing Coach: The military recognizes the effectiveness of slow breathing techniques and uses them during combat scenarios to regain composure and reduce tension. Slow breathing techniques practiced regularly may give long-term repair of sympathetic over-arousal. Furthermore, slow, deep breathing has been proven to produce melatonin, which improves relaxation and is an important sleep-inducing hormone.

Pink and white noise

Adults fell asleep 38% faster while listening to white noise, according to a recent study. Other recent research has found that white noise has a good effect on sleep. According to another study, listening to white noise using headphones improved sleep quality for critically ill patients in a noisy hospital ward in India.

Pink and White Noise: Pink noise has been shown in studies to promote cognitive performance and deep sleep in older persons. It has been established that continuous pink noise substantially reduces brain wave complexity and produces a more stable sleep duration to improve individuals' sleep quality. Meanwhile, some recent studies have revealed relevant evidence. For example, in 2010, light music, an example of pink noise, was found to be good for older persons in terms of improving their sleep quality over time. 

Why do we need deep sleep, and how does FRENZ promote it?

Sleep is essential for survival, and sleep quality is closely tied to overall health. Deep sleep, also known as slow-wave sleep (SWS), is needed for cognitive activities, memory consolidation, immune system growth and repair, and energy replenishment.

Consistent lack of deep sleep has been related to a variety of potentially fatal illnesses, including progressive neurological disorders such as Alzheimer's and Parkinson's. Inadequate SWS intake contributes to insulin resistance, type 2 diabetes, and heart disease. Another key function of SWS is the generation and regulation of hormones, with growth hormone being a prime example. SWS has recently been demonstrated to aid in removing poisons from the brain, specifically amyloid.

As we age, our sleep patterns shift, and our deep sleep episodes get shorter and shallower. Adults over 60, for example, can lose 70% of their deep sleep compared to adults 25 and younger. If older persons' deep sleep declines, they have fewer slow waves at that period, which may lead to cognitive loss. 

The FRENZ™ Deep Sleep Boosting Stimulation function is an audio-based stimulation that increases the prominence and presence of slow oscillations (SOs) in the Deep Sleep Stage. If FRENZ identifies a user in the deep sleep stage, it will attempt to generate small bursts of pink noise at precisely calculated moments to let SOs endure longer. This feature extends deep sleep and promotes memory consolidation in users. 

The effectiveness of stimulation is only possible with the automatic and accurate recognition of deep sleep in near real-time. When the user enters a stable state of deep sleep, the deep sleep-boosting stimulation feature is engaged. When users switch from deep sleep to another stage of sleep or wake, stimulation is paused until they return to a stable deep sleep state. This approach lowers users' mid-sleep awakenings.

The Deep Sleep Boosting Stimulation uses short bursts of pink noise to stimulate the "up-stages" of SOs observed during deep sleep in order to boost memory consolidation and information processing during sleep. FRENZ does not interfere while SOs is in a down-stage since it could interfere with the behavior of slow oscillations.

How much REM is required, and what if I fall short of that?

Infants and children require the most REM sleep since their brains are still developing. Newborns spend eight hours every day in REM slumber. Adults require only two hours of REM sleep every night on average. 

Different animals require different levels of REM sleep. Some mammals, such as horses and elephants, can function with little or no REM sleep, but cats, platypus, and ferrets can sleep for up to eight hours each day. Most mammals, like humans, spend more of their newborn sleep period in REM sleep than they do as adults.

Your body adapts your sleep length based on your physical and energetic demands, both over time and on a daily basis. Similarly, depending on your body's needs, the amount of time you spend in each sleep stage, including REM, may vary from night to night.

Following learning, studies on both animals and people have demonstrated an increase in REM sleep. In one study, rats who mastered a new labyrinth spent nearly a week-long time in REM sleep. Another study looked at the impact of sleep on the working memory of healthy college students. Each day, the students took two exams, with one group napping in between and the other remaining awake. The napping group's accuracy increased in direct proportion to the amount of time they spent in REM sleep during their nap.

REM sleep deprivation appears to impair memory development in people and animals, according to research. On the other hand, memory deficits associated with a lack of REM sleep may result from total sleep disruption, as both are frequently co-occurring. Furthermore, studies of very uncommon individuals who do not experience REM sleep show that they do not suffer from memory or learning problems. A lack of REM sleep, on the other hand, hinders the brain's ability to generate new cells. More research is needed to understand the effects of REM sleep loss better.

Why do I wake up unrefreshed, and how can FRENZ help?

Have you ever wondered why some days we wake up refreshed and others we feel anxious and tired? This fatigue is a physiological state of our bodies known as sleep inertia.

After waking up, people may experience grogginess, diminished alertness, cognitively impaired functioning, and a loss of orientation. Those stages often last 15-60 minutes, but they can persist much longer. Furthermore, when we are in the sleep inertia stage, we may wish to fall back asleep, which results in reduced cognitive capacity, visual attention, and spatial memory.

Rapid awakening from a deep sleep, according to studies, creates much more sleep inertia than other awakenings.  Adenosine levels in the brain steadily rise during sleep deprivation and return to normal during sleep. However, when you wake up after sleep deprivation, high levels of adenosine bind to brain receptors, causing neuronal activity to stop and you to feel tired.

According to research, drinking alcohol in the evening causes body uneasiness when you wake up. This condition is also known as a hangover 

According to a study, a person who wakes up quickly after resting or sleeping is more likely to have issues functioning. Performance decreases upon abrupt awakening from sleep on a wide range of tasks, including simple reaction time (RT), complex RT, grip strength, steadiness, and coordination, visual-perceptual tasks, memory tasks, time estimates, complex-behavior simulation tasks, and many cognitive tasks, including mental arithmetic, cancellation, and clock reversal.

The smart wakeup algorithm of FRENZ™ is made up of two main parts:

Users who wake up in Deep or even REM sleep are likely to feel fatigued, sluggish, and perhaps temporarily bewildered. Meanwhile, upon waking up from a light sleep, users are less likely to feel increased grogginess, lethargy, and/or sleep inertia. As a result, FRENZ created logic to determine when to sound the alarm to wake the user up 

We develop a content recommendation algorithm that selects calming noises to wake up the user slowly. This method also includes automatic volume adaptation.

About Earable® Neuroscience

Earable® Neuroscience U.S. is a deep tech company delivering scalable, human-centric solutions that improve the everyday experience — from deep sleep to all-day focus. 

Tam Vu is the Founder and CEO of Earable® Neuroscience, the company behind the FRENZ™ Brainband — the world's first consumer brainband that can measure and stimulate brain activity with clinical precision, so you can sleep more deeply, find sharper focus, and unlock your brain's true potential. It is the recipient of multiple scientific awards and holds 15 patents globally.

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