Updated: Dec 6, 2020
If you know me well, you know I love to sleep. I've sacrificed sleep for studying (what student hasn't?) and competitively trained as an athlete after being chronically sleep deprived.
Last year, I stumbled upon Matthew Walker's book Why We Sleep and my poor classmates (who probably own earplugs now) have heard me rant on and on about how amazing this book is. So I decided it was time to put together a list of the the juiciest parts.
The Sleep Debt
If you haven't heard of Adenosine here is the down low. It's a neurotransmitter found normally in our brain. Adenosine rises as we wake up in the morning & causes us to be sleepy by bedtime. In contrast, levels of adenosine fall as we sleep. However, If (when?) you constantly are lacking sleep, adenosine is carried over to the next day, and the next, and the next. Creating something comparable to a debt. The idea is that sleep deprivation is additive, it collects interest. You can't pull on all nighter as a student and think you can "catch it up" with a sleep filled weekend.
What's MORE interesting is that the research on sleep deprived individuals shows that we don't even realize how fatigued we are. We think we are fine. The low level of fatigue, reduced altertness, and poor performance becomes our new normal. Sound familiar?
Why Do We Sleep?
Earlier in the night, we get more NREM sleep which consolidates information into our long term memory and finesses motor skills (athletes & gym rats take note). It also filters out the unimportant connections, and strengthens memory of important information.
REM sleep i.e. dream sleep which occurs early in the morning hours has two functions.
One it allows us to recognize and understand emotional intelligence and social factors such as facial expressions, gestures and behaviours. It gives us the ability to control our own emotions and realize how others are feeling.
Secondly, REM sleep allows us to integrate experiences and knowledge throughout our lives to gain greater insight & associate seemingly unlike events.
Research supports learning first, then sleep to press save.
In fact, new information is vulnerable for even up to 3 nights after learning something new. A study found that students who learnt something new, had two nights of sleep, and then drank before bed on the third night had a 40% decrease in memory. Alcohol disrupts sleep by decreasing time spent in REM sleep & increasing the amount of times you wake up throughout the night.
So you stayed up all night studying, watching Netflix, or just procrastinating because you don't want it to be Monday. The solution? Coffee. It keeps you awake & functioning at your job, the seasonal cups are adorable, and the caramel sprinkles on whip is delicious. I get it, lots of pros.
However, coffee acts by blocking adenosine receptors. It stops the body from seeing the sleepiness signal. Which sounds great, but adenosine is still building and once coffee is removed, adenosine floods the body causing a "crash" of extreme sleepiness.
Why you feel terrible when sleep deprived
Nerd moment: one of my favourite medical words is amygdala (Ah-mig-dala). It's the emotional centre of our brain that deals with anger, rage, and fear. Turns out sleep deprivation intensifies this area of the brain by 60%. Every new parent is cringing right about now.
However, it's not just anger and rage. Any brain lacking sleep fluctuates between elated and pessimistic. Studies have associated sleep deprivation with depression, suicidal thoughts, aggression, bullying, behavioural issues, violence, increased risk taking, and addiction. Note that many psychiatric disorders such as depression, anxiety, bi-polar, PTSD all have sleep related symptoms. Matthew Walker recommends seeking out a sleep therapist and/or cognitive behavioural therapy for insomnia.
Dreams (I.e. overnight therapy)
Dreaming was found to reduce emotional pain attached with memories. Research shows that dreaming of the emotional trauma helps resolve how we encounter these emotions whilst awake. Dr. Cartwright found that when patients with depression or anxiety caused by emotional distress dreamt of their sufferings it offered closure and remission of symptoms.
In hopes that you fell asleep reading this,
Lemoine, P., Nir, T., Laudon, M., & Zisapel, N. (2007). Prolonged‐release melatonin improves sleep quality and morning alertness in insomnia patients aged 55 years and older and has no withdrawal effects. Journal of sleep research, 16(4), 372-380.
Milewski, M. D., Skaggs, D. L., Bishop, G. A., Pace, J. L., Ibrahim, D. A., Wren, T. A., & Barzdukas, A. (2014). Chronic lack of sleep is associated with increased sports injuries in adolescent athletes. Journal of Pediatric Orthopaedics, 34(2), 129-133.
Walker, M. (2017). Summary of Why we sleep: Unlocking the power of sleep and dreams by: Matthew Walker. New York, NY: Scribner.
Note: This blog post is for educational purposes. this is not medical advice. If you wish to seek out medical advice for insomnia or other health concerns please consult a qualified healthcare provider or ND.