Last night I went out with my friends to our local tavern for some beers. Before that, I was reading a book by the Nobel Laureate Gerald M. Edelman. I was trying to figure out his theory on “Neural Darwinism,” but, after some pages, I thought it was appropriate to go out for some good old beers. I drank a wide variety, from IPAs to even some European darks. Needless to say, I got drunk and walked back home early in the night so I couldn’t extend such a dangerous and humiliating state.

When I arrived at my apartment, everything was spinning; the only satisfactory thing that I had was a hot bath and the comfort of my bed. I went to bed early, at 9:00 p.m., and thought that a good night’s sleep was coming. Boy, was I wrong!

Alcohol Is Killing Your REM Sleep

Losing Sleep after a Night of Beers

For the next few hours, I slept like a baby, such was my sedation. That’s why they call alcohol a “sedative”: it sedates structures of the brain when consuming it. But then, at 3:00 a.m., I woke up from my slumber, with my heart racing fast and my breathing rate through the roof (probably because I was on one of my REM sleep periods). I went to the bathroom and went back to sleep. At 5:00 a.m. the same thing happened, with the same physiological effects. Later, at 6:30, it happened again.

The good night’s sleep I was looking wasn’t that good at all. My periods of dreaming were constantly interrupted, and the quality of my sleep after 3:00 a.m. plummeted – probably because my liver had effectively removed only part of the alcohol in my system.

You’re probably thinking, “What’s the big deal? Don’t drink today and get to bed early so you can recuperate the loss of sleep.” That’s true in some sense, but if we do research on what I lost thanks to alcohol, you’ll think otherwise.

Why We Sleep

In fact, after getting back to my normal state, something shocking happened. I re-read the pages of Edelman’s book and I couldn’t remember the main facts on Neural Darwinism. This made me re-read another book, but about sleep. I checked Matthew Walker’s Why We Sleep book and discovered the consequences of my alcohol consumption last night.

As Walker explains, “alcohol fragments sleep, littering the night with brief awakenings. Alcohol infused sleep is therefore not continuous and, as a result, not restorative.”

Further, Walker explains the poor quality of my dream state (Rapid Eye Movement Sleep or REM sleep):

“[A]lcohol is one of the most powerful suppressors of REM sleep that we know of. When the body metabolizes alcohol it produces by-product chemicals called aldehydes and ketones. The aldehydes in particular will block the brain’s ability to generate REM sleep. It’s rather like the cerebral version of cardiac arrest, preventing the pulsation beat of brain waves that otherwise power dream sleep. People consuming even moderate amounts of alcohol in the afternoon and/or evening are thus depriving themselves of dream sleep.”

When I re-read those facts my brain almost exploded, it was so obvious and at the same time, so damaging what I have done. I deprived my body of one of the most important states of the brain that has been shown to shed light on memory storage, emotional perception and even creativity.

The Importance of REM Sleep

Rapid eye movement or REM sleep was discovered in the 1950s at the University of Chicago. Researchers observed the eye movement of infants in sleep states. After replicating the experiments, the group of researchers, which included the legendary sleep scientist William Dement, discovered two distinct patterns of sleep: Non-Rapid Eye Movement sleep (NREM) and the one I suppressed with alcohol last night, REM sleep.

Dream Weaver

As Walker explained in his book, the brainwaves of REM sleep are almost identical to brainwaves when someone is awakened, such a connection made scientists conclude that dreams happen in REM sleep.

But, why is so important to dream? We forget most of our dreams, and they rarely tell us something about the future. In the last 20 years of research, scientists have expanded on the state and have discovered unique effects of REM sleep in our body.

First, dreams alleviate the pain of a bad emotion or emotional episode that happened before sleep. The brain during REM sleep takes over the noradrenaline, a neurotransmitter related to stress and the regulation of the amygdala (a very important structure in your brain related to emotional reactions). As Walker explains, your brain completely shuts off the stress hormone during the dreaming sleep state.

Read You Like a Book

REM sleep also helps us decode or read emotional expressions. As humans, we are highly social animals, and recognizing patterns of emotions in people’s faces is important. Scientists have found that the better the quality of sleep, the more easily a person can recognize another one’s emotion. If the opposite happens (poor sleep), then people could have a hard time recognizing emotional states. Moreover, some people reach the wrong conclusion when interpreting someone’s emotional patterns.

Memorization and Creativity

The last two big effects of REM sleep are probably the most important ones.

First, scientists have shown that during NREM sleep, recent memories or short-term memories are relocated into more long-term memory. But during REM sleep, the brain moves those newly acquired memories and applies them to other memories in the brain.

Second, creativity has been shown to be a key part of dreaming, which happens during REM sleep. You can go to sleep with a problem that you are unable to solve, and voila! In the morning, you have the answer to the problem. This, of course, is thanks to the memory movement during REM sleep and how such a state is free from the mental constraints that come with being awake. One legendary example is the tale of Dmitri Mendeleev resolving the organization of the periodic table after falling asleep from exhaustion.

Last Word on REM Sleep and Alcohol

With all the factors in mind, it’s no wonder why I was alarmed after my night out of beers. My brain was incapacitated and was deprived of a vital state. REM sleep can basically decide if you’re the next big discoverer or the one unable to finish the metaphorical race. I will now sit down and read Edelman’s book and bear in mind how a non-alcoholic sleep can help me understand Neural Darwinism and the mystery of consciousness.

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