We all know the difference between how we feel after a quality night's rest, and how we feel after a poor night's sleep or a short night's sleep. The latter is a struggle. The feeling of barely being able to keep your eyes open, or actually daydreaming about getting to go to sleep again. In some instances, the sleep disturbance is clearly known- you may have stayed up late working and cut into your sleeping hours. Or you may have partied and danced the night away. Those decisions are ones that often are carefully weighed out and decided with the known factor that sleep will be put on the back burner. These types of sleep choices are fine once in a while. However, there are many instances where you may be lying in bed at night, closing your eyes and wanting to sleep, but struggling to fall asleep. Or you may be a new parent and sleep feels almost non-existent. Whatever the sleep issue, it's important to know why sleep is so important and so much more than just feeling "sleepy" the next day.
According to a 2020 study from the Cleveland Clinic, "about 70 million people in the United States suffer from sleep disorders." This does not account for the individuals who suffer from poor sleep or sleep issues (ones that do not meet the diagnostic criteria for a sleep disorder) (4). Please refer to the end of the blog for a brief summary of each sleep disorder noted in the Diagnostic Statistical Manual of Mental Disorders, 5th Edition (DSM-5).
Your Brain During Sleep
If sleep wasn't so important, it wouldn't be something that we are wired to do daily. It's required just as food and water are required for survival. Sleep is an integral part of the bodily process because of the restorative work the brain is doing during the night. There are several brain areas at work when the body sleeps, not to mention the thousands of neurons that are only activated during sleep.
When we sleep, the brain regenerates damaged brain cells and regulates neurotransmitters The neurotransmitters or chemical messengers that send signals throughout our body are working 24/7. These neurotransmitters operate everything within our brain and body and are subject to many dangers. The "threats" to the central nervous system can include lifestyle choices, genetic predispositions, injuries, aging, normal wear and tear, nutrition deficits, etc. At a molecular level, neurological damage can include things like:
the cells that receive information too quickly so they cannot absorb the information properly which causes damage to the cell (think of shoving too many clothes into a drawer and trying to shut it- it won't work and damages the tracks on the drawer).
certain enzymes, such as "free radicals" which are stored up in the cells and cause damage to other cell molecules. Free radicals are a common byproduct of cell metabolization but when they are built up in the cell they cause damage to that cell (whether it be a muscle cell, DNA cell, protein cell, etc).
The damage to the nervous system results in many brain and body issues such as brain fog, memory loss, disease, digestive issues, unstable moods, etc.
The natural repairing of these cells happens when we sleep. The repair process includes the release of certain enzymes. Every enzyme that is released serves a different restorative purpose. Here are a few examples of what happens in the brain during sleep:
Melatonin regulates sleep patterns
Metabolic hormones regulate glucose homeostasis
Sex hormones regulate estrogen, progesterone, and testosterone levels
Cortisol (aka the stress hormone) decreases
The neurotransmitters GABA and glycine reduce motor movements and allow for REM sleep to occur
Acetylcholine is released to enhance memory functions
Glial cells eliminate toxic proteins and waste
Sleep Stages: When we sleep, we cycle through 4 different stages. During each cycle, the first three stages of sleep shorten in duration, allowing the REM sleep stage to get progressively longer.
Stage 1: is the lightest stage of sleep, lasting only several minutes. This is when the body regulates autonomic functions so deep sleep can occur.
Stage 2: is a slightly deeper sleep state when the muscles relax even further, body temperature drops, brain wave activity decreases, and eye movements top. This is the most repeated sleep stage during a normal sleep cycle.
Stage 3: is the period of deep sleep that occurs during the first half of a normal sleep cycle. Heart rate and breathing are at their lowest rates during this stage. Muscles are the most relaxed and brain waves reduce even further. This is the stage of sleep that is most needed to obtain quality sleep.
REM sleep: involves the process of your eyes moving rapidly from side to side while your eyes are closed. The first occurrence of REM sleep is about 90 minutes after falling asleep. Brain activity increases and is more similar to a wakeful state along with breathing and heart rate. Dreaming is most likely to take place during REM sleep and motor movements are deeply impaired as a result of ensuring that the body doesn't react to dreams. During this stage, memories are sorted and consolidated.
Sleep Hygiene Tips
Eliminate as much artificial light as possible at least 30 minutes before sleep.
Engage in moderate movement for at least 30 minutes a day.
Research what to eat and what not to eat before bed.
Aim to sleep when the sun goes down and wake when the sun comes up (as close to this cycle as possible).
Natural light exposure first thing in the morning can help regulate cortisol levels and circadian rhythm.
Eliminate the use of substances or excessive caffeine.
Speak to a medical professional if there is any concern for a possible sleep disorder.
Work on anxiety-reducing techniques such as diaphragmatic breathing thought stopping, spiritual practice (i.e. prayer), etc.
Sleep Disorders
Hypersomnolence Disorder: excessive sleepiness despite the sufficient quality of sleep.
Insomnia: difficulty falling or staying asleep or difficulty obtaining quality sleep.
Circadian Rhythm Sleep-Wake Disorders: sleep disruption caused by an alteration in the physical environment that leads to a misalignment in sleep-wake patterns with natural circadian rhythm.
Narcolepsy: the sudden need to sleep, lapsing into sleep, or napping recurrently in the same day. The disorder can also include the presence of cataplexy which includes the shutting down of muscle control with maintained consciousness.
Nightmare Disorder: well-remembered dreams that impose threats to survival, security, and physical integrity and result in disrupted sleep.
Non-Rapid Eye Movement Sleep Arousal Disorders: include the disruption of sleep characterized by the first third of the sleep cycle that is usually accompanied by sleep behaviors such as sleepwalking.
Rapid Eye Movement Sleep Behavior Disorder: repeated episodes of arousal during sleep that are paired with vocal or motor behaviors (typically a response to a dream). The behaviors are present during REM sleep.
Restless legs syndrome: a disorder characterized by the strong urge or impulse to move. It can include moving any part of the body as a response to a sensation described as tugging, itching, throbbing, burning, etc.
Sleep apnea (obstructive, central: a condition that results in restricting the airways when you sleep, causing failure to breathe. When this happens, the brain forces awakening which impairs one's ability to sleep or obtain quality sleep
Sleep-Related Hypoventilation: decreased respiration associated with elevated C02 levels.
Substance/Medication-Induced Sleep Disorder: Severe disturbance in sleep while under the influence of a substance or medication.
Sources
1. Boto T, Tomchik SM. The excitatory, the inhibitory, and the modulatory: mapping chemical neurotransmission in the brain. Neuron. 2019;101(5):763-765. doi:10.1016/j.neuron.2019.02.021
2. Brain Basics: Understanding Sleep | National Institute of Neurological Disorders and Stroke. (n.d.). https://www.ninds.nih.gov/health-information/public-education/brain-basics/brain-basics-understanding-sleep
3. DSM-5: Diagnostic and Statistical Manual of Mental Disorders, 5th Edition. (2023). Generic Tyzek.
4. Neurotransmitters: What They Are, Functions & Types. (n.d.). Cleveland Clinic. https://my.clevelandclinic.org/health/articles/22513-neurotransmitters
Additional Sleep Support Resources:
Comments