Lost sleep results in a less effective brain and less healthy body.
When we’re trying to get more out of life, sleep is usually the first thing that gets cut out to make room in our schedules. Ironically, it can be hard to realize that by cutting back on sleep, we are decreasing productivity, creativity, patience, communication skills, and a lot of what makes a good human. Lost sleep results in a less effective brain and less healthy body. Pretty much whatever you are doing, you end up doing it worse.
Why Sleep is Critical for the Body & Brain | Science of Sleep Part I
|What I’ve Learned|
Key Takeaways
Studies showed that without sleep, the brain loses its ability to consider alternative solutions to problems. Brain scans have shown that when you’re lacking sleep, the neurons firing in the prefrontal cortex begin to slow down. The prefrontal cortex is particularly responsible for the behaviors that make us human. This region is associated with planning, decision making, attention control, reasoning, and problem-solving.
When you lack sleep, it’s harder for us to complete a thought or see a problem in a new way. You can gain insights when you didn’t even know there was an insight to find, just by sleeping on it. Two big things that allow for such insights are memory consolidation and information processing. While asleep, your brain looks at the information you picked up throughout the day, prunes out the useless junk and keeps the things worth remembering.
Of the four stages of sleep, slow wave sleep and rapid eye movement have been shown to move electrical impulses between the brain stem, hippocampus, thalamus, and cortex. These four areas serve as relay stations for memory formation. During this process, your brain takes the information in the short-term memory and moves the important bits to long-term memory. During the non-REM deep sleep phase, your brain is quickly reviewing the information you’ve gained throughout the day and taking notes.
Insufficient sleep also interferes with your personality and competence in general. The Prefrontal Cortex shows less activity when you’re sleep deprived. The Amygdala shows more activity, which is associated with processing emotional information and a study shows the lack of sleep inappropriately modulates the human emotional brain response to negative aversive stimuli. The less sleep you get the more likely to interpret situations negatively, overreact to things and be more moody in general.
Only 5% of the population has the genetic mutation that lets you get by on only 6 hours of sleep. Activity in the Prefrontal Cortex lessens when you lack sleep and the Prefrontal Cortex is the only part of the brain that has the power of self-assessment to think about how it is thinking. So if you’re not getting enough sleep, would your Prefrontal Cortex properly recognize that it’s working at sub-optimal capacity?
The military has spent millions of dollars testing all kinds of methods to keep soldiers awake longer but in 2007 they concluded that the only way to recover from lost sleep was to sleep.
It’s not only your brain that needs sleep, also on the sleep to do list is tissue repair, maintenance of metabolic pathways and balancing of hormones. Sleep is also very important for your body. Studies show that sleep deprivation increases levels of Ghrelin. Ghrelin is a hormone that causes you to retain fat and feel more hungry. It has been shown that just one night of poor sleep leads to a 15% increase in this “hunger hormone.”
Lack of sleep also means lower levels of the satiety hormone, leptin, and less melatonin. Melatonin has some powerful anti-aging and anti-cancer properties and the Journal of Pineal Research found, melatonin increases weight loss by increasing brown adipose tissue. Brown adipose tissue or BAT fat act a lot like muscle meaning that it increases your metabolic rate and burns white adipose tissue.
Inadequate sleep also increases cortisol which has been shown to increase the worst type of fat, visceral fat, the stuff that surrounds your organs. Cortisol also encourages your body to break down muscle for fuel through a process called gluconeogenesis.
One more key hormone secreted during sleep is Human Growth Factor or HGH, the youth hormone. It stimulates growth, cell reproduction, and cell regeneration which means increased muscle, more fat loss, and other things like improved skin elasticity. Human Growth Hormone even plays a role in improving cognitive function and a deficiency in it has been linked with depression.
It’s important to get enough sleep, but it’s also important to get it at the right time. While it depends on each individual’s Circadian Rhythm, in general 10PM-2AM is when your body secretes the most Growth Hormone.
The other important thing on the Sleep To Do List is waste clean up. Throughout the course of the day, the brain produces a decent amount of waste. The brain handles this waste cleanup task during sleep via something called the “Glymphatic System” in which brain cells shrink to allow for cerebrospinal fluid to flood into the brain and flush out the waste. One thing that needs to be flushed out is the compound adenosine.
Adenosine is a byproduct of your neurons and other cells when they burn up adenosine triphosphate, the main molecule our bodies use to store energy. As adenosine builds up, you start to slow down and accumulate “a Sleep Pressure” When your adenosine levels reach a certain point, your body sends you signals to go to sleep. Caffeine works by bonding to the same receptors as adenosine, tricking the body into thinking it’s not tired.
While caffeine will wake you up, it will interfere with your sleep cycle if taken too late in the day. A study shows that taken caffeine even 6 hours before bed can lead to a measurable objective loss of 1 hour of sleep. This means you’re not properly dipping into the sleep cycles of REM and deep sleep, leading to an actual sleep total of 6 hours. For this reason, it’s recommended to finish your caffeine intake at least 8 or more hours before bedtime.
Like adenosine, Amyloid Beta is another waste product that is created in the brain. Excess Amyloid Beta is toxic to the brain and Amyloid plaques have been thoroughly linked to Alzheimer’s disease. While diet could also play a role, sleep could be critical for avoiding neurodegenerative disease.
Without enough sleep, our bodies, as well as these creative, insightful and emotionally adept faculties of our human brain suffer.