Plugging in to The Power of Sleep: When to Snooze and When You Lose
May 15, 2019
Every time I see that my cell phone is low on battery power, I panic. Immediately, I start searching for a power source. I worry about my phone’s ability to function.
So why do I disregard my own ability to function? Why do I often ignore my need for sleep and fail to recharge my own battery? Groggy, I often ponder these priorities every morning when I hit the snooze button. Yes, I know I should go to bed earlier. I am heading off to college soon, so I have started to consider how to manage my sleep needs better and assess why I rely on an alarm clock.
The arrival of Spring makes waking easier, because early morning light wakes us not just because it is bright, but because it activates our circadian clock. This innate clock is our biological alarm which is engaged by triggering light sensitive proteins in the back of our eyeball, in our retina. These proteins send signals to the brain’s suprachiasmatic nucleus (SCN). The SCN is a pair of tiny, symmetrical wing-shaped clusters of cells in the brain’s hypothalamus. The SCN works to help the pineal gland to manage and release melatonin. Melatonin is our body’s natural sleep-inducing hormone. It helps muscles relax, promotes feelings of drowsiness, and aids sleep by dropping body temperature. Melatonin levels rise during the early evening as darkness falls and continue to rise throughout the night, before reversing production around 3 a.m. Approximately at that hour, levels of melatonin then start to decrease and stay low during much of the day. The SCN is integral in sending a signal to regulate the body in this way and to stay on an approximately 24-hour schedule.
Our ancestors were easily in sync with the regularity of their 24-hour clock, relying only on sunlight to dictate the arrival and conclusion of each day. Today, electricity, artificial light and technology screens interrupt the efficiency of our internal 24-hour clocks. Environmental cues disrupt the clock. Discipline is required to begin bedtime and to induce melatonin, crucial for a good night’s rest.
Sleep is biologically intrinsic to our protection and ensures our survival. Distant ancestors retreated to caves to sleep when the sun went down. This provided automatic protection, because it mitigated risk and prevented navigation in dark nights with poor visibility. Protection encourages survival, because it increases continuation and offspring.
Today, we still need sleep to survive and to cope. Sleep helps to regulate stressors and to manage our primal fight-or-flight response in our daily lives. Rest protects resilience and mental health. There are regions in the brain that aid this effort specifically. The amygdala, the hippocampus and the prefrontal cortex work in conjunction with the hypothalamus to regulate stress hormones or related responses, such as an increased heart rate. Research proves that stressors can physically alter our brains. Stressors affect how we learn, form memories and even make decisions. This explains why it is particularly difficult to cope when fatigued.
Each night, about every 90 minutes, the mind and body cycle through four different stages of sleep. Each stage lasts from five to fifteen minutes. The first stage is NREM-1 sleep. This stage offers fleeting images, is the lightest, most easily disturbed sleep and exhibits very slow eye movement. Muscles relax and breathing slows down. Next, the NREM-2 stage prepares the body to reduce activity, to decrease awareness and to begin a deep sleep. Most of the sleep enjoyed at night is spent in this longer stage. The heart rate slows down and the body temperature decreases. The brain is working minimally during this stage too. NREM-3 is the deeper sleep stage that is initially disorienting if woken during this period. These non-REM stages of sleep help the brain learn better the next day. The REM stage is the coveted dream-like sleep when the brain is highly active and there is rapid eye movement. This stage encodes new memories, links related memories and processes the more emotional ones. This stage also nourishes creative thinking and problem solving—which is perhaps why some dreams are so vivid. Throughout the night, the time spent in these stages also begins to shift. Regardless of when sleep begins, NREM sleep is experienced with more frequency in the earlier hours of the night. REM sleep will experience longer cycles throughout the evening and be heavily enjoyed in the later hours of the night.
When we fail to be faithful to our sleep needs, our circadian rhythm is interrupted and our physiological processes are compromised. While sleeping, brain tissues are repaired and the immune system replenishes itself with the release of compounds called cytokines. A reduction in sleep jeopardizes the ability of cytokines to fight inflammation and infection. Proper rest also aids growth by releasing growth hormones from our pituitary gland, which are needed for muscle development. Better sleep promotes a good diet and helps the body suppress ghrelin, a hunger hormone, and stimulate leptin, which controls appetite and keeps will power strong. Good sleep also controls the hormonal levels of insulin and cortisol, increasing hunger to encourage breakfast consumption so that daytime stress is less taxing. Conversely, reduced sleep leads to sustained stress and imbalances proper levels of cortisol, which negatively expresses itself physiologically. Reduced sleep also causes imbalances in levels of prolactin, which can also weaken the immune system, increase difficulties with concentration and incur erratic carbohydrate cravings.
Although I have been hitting the snooze button trying to get more sleep, I may not be doing myself a favor. When trying to catch just a few more precious minutes, I risk entering a new sleep cycle which makes me prone to deeper sleep. Most snooze buttons offer a reprieve of nine minutes before the alarm rings again. When I enter another sleep cycle, I tend to feel even more tired than if I had risen with the alarm. This common occurrence, what scientists refer to as fragmented sleep, is preventable. Yet, many do not even recognize that this happens. That groggy feeling, after waking from the snooze button, leaves morning risers struggling with sleep inertia. This is basically the body attempting to continue the sleep cycle even though it is awake. Accrued sleep deprivation or abrupt disturbances during NREM-3 deep sleep often precipitates this. Normal lower levels of blood flow to the brain upon awakening also contribute to the sleep inertia period.
Ideally, it is best to sleep for as long as I need to and to wake naturally without a snooze button. Alas, this is not always an option, but I can start making changes to ensure better sleep. I can try to begin my bedtime routine sooner, shut down light sources and aim for a consistent bed time. Watching what and when I eat, coupled with maintaining an exercise routine, will certainly aid my cause too. I will probably still need an alarm clock, but I may aim to beat the clock on weekdays, welcome natural light with open shades on weekends and certainly try to avoid the snooze button.
Well trained sleep habits offer exponential benefits. There is a correlation to being more at risk for chronic disease, anxiety, depression heart disease, obesity, diabetes, dementia and increased mortality. Poor sleep habits impair the ability to drive safely as well. Dedication to proper sleep habits can avoid these associated risks and foster a more enjoyable, productive, creative and healthy life.
So, the next time you plug in your phone, be sure to plug yourself in early too!