Your Brain Has a Night Shift

In the last post, we left you unconscious. This seemed a little rude, but it was necessary. You had spent the day learning things, making decisions, dealing with people, solving problems and giving your developing brain a large pile of experiences.

Then you went to sleep. Your brain did not.

Sleep can look like eight hours of absolutely nothing happening. You are lying there. Your eyes are closed. You are contributing very little to the conversation. Inside your brain, however, critically important work continues. Sleep is necessary for learning, memory, attention and the systems that help regulate emotions the next day.

Sleep is necessary for learning, memory, attention and the systems that help regulate emotions the next day.

What Happened to Today?

You learned something new in class today, and then maybe something new about interacting with friends. While you are experiencing or learning it, a brain structure called the hippocampus is involved in capturing the new memory. But the hippocampus only captures that new learning experience. To not lose the new learning, your brian has to get to work to make the new information permanent and this is primarily the work of the brain during sleep. During sleep the brain continues processing, sorting and strengthening pieces of what you learned and experienced today, even what you are learning right now will be stored until tonight and then more deeply processed.

During sleep the brain continues processing, sorting and strengthening pieces of what you learned and experienced today.

This is the reason sleep matters when you are learning a new skill too. You practise a guitar chord, basketball move, dance sequence or something else that initially feels awkward or impossible. Your fingers or feet appear to have resigned from the project. You practise again. Here sleep becomes part of what happens between today's practice and tomorrow's attempt. Your developing brain also relies heavily on networks involving the prefrontal cortex. Remember that area from the last post? The prefrontal cortex helps with planning, attention, decision-making and controlling behaviour. Sleep supports how effectively these systems, especially well-being function the next day.

And this is where sleep starts becoming very interesting for mental well-being.

Tomorrow Arrives

Suppose two versions of you arrive at school: One slept well. The other was awake much too late and has been separated from their bed against their wishes. Both encounter the same annoying situation. The well-rested brain still might become irritated. Sleep does not transform anyone into a permanently peaceful mountain monk. But after too little sleep, attention, decision-making and emotional regulation will become more difficult. Frustration may arrive faster. Concentrating takes more effort. An ordinary problem will feel considerably larger.

Notice what happened there.

The situation did not necessarily change. The conditions inside the brain trying to handle it did.

That is, your mental-well-being. How you show up for today is directly related to how you took care of your sleep. In summary, how you feel on a particular day is affected by what is happening around you, but more importantly, by the condition of the brain and body you brought into today that has to face it and respond to it. Sleep, it is a critical role in what that will be.

Thought exercise:

How do you want to feel or experience your day tomorrow?

How do you feel the next day after a poorly managed night's sleep?

There Is One Slight Problem

During adolescence, the body's internal timing naturally begins shifting. Many teenagers start feeling sleepy later at night than they did when they were younger. That is partly real biology, not simply teenagers collectively deciding that bedtime is unreasonable. Unfortunately, morning did not receive the memo, “brain needs more sleep”.

School, activities and other responsibilities will still begin earlier than your brain and you are ready for. Then to the night before, add homework, friends, entertainment and a device capable of producing something new every three seconds, and sleep can get tightly squeezed from both ends. The result is not just “being tired.” Repeatedly getting too little sleep immediately affects learning, attention, mood and emotional regulation. But over time, it hits how you feel, more and more. This does not mean one late night has ruined your brain. Bodies are much more adaptable than that. What matters more for health is the repeated pattern over time. You really need to be the protector of your sleep. No one else can be.

You really need to be the protector of your sleep. No one else can be.

The Night Shift Matters

Think back to the brain from our first post. It is developing while handling new experiences, greater independence, changing relationships, social comparison and increasingly complicated decisions. All day long, that brain is being asked to learn.

Sleep is the critical part of the things you have control over to support new learning.

So sleep is not simply the empty space between today and tomorrow. Your sleeping brain is processing, sorting and organizing today’s information, supporting memory while other systems recover and ready themselves for another day tomorrow. The quality of tomorrow's attention, learning and emotional regulation depend on what happened overnight. And tomorrow will almost certainly need your attention, readiness to learn, and emotional best . Especially if somebody replies: “K.”

Vocabulary

• Prefrontal cortex: The front part of your brain that helps you plan, control impulses and make decisions.
• Hippocampus: The part of your brain that immediately stores today and is critical to building and organizing new memories. It is very sensitive to sleep in order to do its job.

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