This Is How Lack of Rest Affects the Brain

There's no questioning the fact that a lack of rest affects the brain. When we sleep poorly, we're irritable and less connected the next day. Learn the science behind why a lack of rest affects our brains in this article!
This Is How Lack of Rest Affects the Brain

Last update: 03 September, 2021

When there’s a lack of rest, functions in our brain begin to lose effectiveness. We feel slower to respond, have less memory, and experience significant muscle fatigue.

All these effects have a scientific explanation, and it points to the importance of brain tissue for daily life. However, optimal maintenance of this tissue requires sufficient sleep.

Various factors play a role in the lack of rest. Some people sleep poorly due to psychological disorders, such as anxiety insomnia, and others sleep poorly due to bad bedtime habits.

The situation is quite serious in the long term. Let’s think that a student who sleeps poorly and, as a result, won’t be able to advance adequately in their career. Or think about a worker who won’t perform as well in their job, and will even run vital risks if they operate machinery, for example.

What happens to the brain due to lack of rest? What are the processes that lack of rest affects?

Below, we’ll review the effects of lack of rest on three main areas associated with brain health: Mood, memory, and circadian rhythm.

Lack of rest alters your mood

Parents who’ve pulled all-nighters for their children know this. The next day is full of irritability, and everything seems to make us too angry, even the smallest things.

This mood disturbance stems from the disconnect that lack of rest causes between the brain amygdala and the rest of the nervous system tissue. A disconnected amygdala acts by impulses, without mediating actions in the cortex of the brain.

The negative becomes more negative and even worse in the amygdala’s interpretation of things. Under normal conditions, with enough sleep, that way of interpreting passes through other brain barriers, which elaborate a more appropriate response. After a sleepless night, there are no limits to our anger.

It’s not a permanent effect, as, after sleeping the necessary hours, the system reconnects again. However, in people with poor sleep, irritability can often significantly alter their social relationships.

A doctor pointing to a plastic model of the brain.
Scientific research on sleep confirms that poor rest alters brain tissue.

Continue reading: Going to Sleep Late May Increase Risk of Obesity, Studies Show

A lack of good sleep causes poor exam results

Sleep research points to the hippocampus as another region hit hard by lack of rest. This area is key for students, as it’s where memory is made.

A poor night’s rest reduces the chances of retaining new information the next day. It even ruins the retention of images, beyond data, which can affect the elaboration of memories of the previous day and the day in progress.

This reinforces the objective of achieving adequate sleep hygiene in students, especially university students. Professional careers demand a degree of attention and retention that can be stimulated by nighttime sleep.

When sleeping, the hippocampus transfers memories from its neurons to other brain lobes. This process is essential for the recording of thoughts and their future settlement.

Lack of rest and melatonin

Humans move in a daily circadian rhythm that lasts about 24 hours. This wake-sleep cycle has been stipulated, externally, by the hours of sunlight. Inside the body, this regulation responds to the hormone melatonin.

Melatonin stops its production when it receives light, and conversely, it’s produced in greater quantities in the dark. This way, the hormone increases its concentration to encourage us to sleep and rest.

Not resting during the right hours pushes back our biological clock and throws us out of the regular wake-sleep cycle. This wrongly exposes us to light, both solar and artificial, which alters melatonin production.

In the medium term, if the wake-sleep cycle is constantly shifting schedules, we can enter phase shifts. This means that we find it increasingly difficult to sleep at the time we want to sleep, and we find it increasingly difficult to wake up to be active in the morning.

A woman who can't fall asleep at night.
A consequence of lack of rest is a decrease in melatonin production.

Sleep hygiene for lack of rest

We’ve seen how lack of rest affects the brain, but there’s something we can do. There are sleep hygiene measures we can take to help our brain tissue function properly.

Let’s remember that through the nervous system, we communicate with the outside world and with our loved ones. So, taking care of it is a priority. A good rest will ensure a better mood and more attention the next day.

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