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Lack of Sleep: The 10 Most Profound Psychological Effects

lack of sleep

Lack of sleep may feel horrible, but what is it really doing to the mind and brain?

American Randy Gardner holds the record for the longest ever scientifically documented intentional period without sleep.

Without the aid of stimulants, he managed to stay awake for 264.4 hours, or 11 days and 24 minutes.

Part of his motivation was to show that lack of sleep isn’t that bad for you.

He was wrong: it is bad for you.

In fact he suffered paranoia, hallucinations, moodiness and a whole host of psychological problems, many described below.

It’s just he did not notice many of the problems: that’s how lack of sleep gets you.

Here are 10 of the most profound psychological effects of lack of sleep, on top of the fact that it feels horrible.

1. Sleepy brains work harder

Since brains that are sleep deprived aren’t as efficient, they have to work harder.

This has been demonstrated in brain imaging studies which show the brains of the sleep deprived desperately pumping energy into the prefrontal cortex, trying to overcome the effects of sleep deprivation.

2. Short-term memory is shot

Lack of sleep causes sharp decrements in working memory.

Without short-term memory a person can’t even hold a few digits of a telephone number in their mind, let alone perform any complex tasks.

That’s why, when you’re sleep deprived, you keep going around in circles.

On day 11 of his sleep record, Randy Gardner was asked to repeatedly subtract 7 from 100. He stopped at 65 saying he had no idea what he was doing.

3. Long-term memory is shot

Sleep plays an important role in consolidating memories.

While we sleep, our brain orders, integrates and makes sense of things that have happened to us.

Not only that, but we seem to consolidate our learning while we sleep.

Lack of sleep badly disrupts this process, meaning it’s difficult to lay down long-term memories and it’s harder to learn new skills.

4. Attention is shot

At our best, humans have incredible powers of attention: we can distinguish one voice from many, track small, moving objects in a sea of visually distracting information and more.

Lack of sleep, though, causes many of these precise powers to go downhill. Without enough sleep, we can’t pay attention to our senses as well as we would like.

This partly results in that weird distracted feeling you get when tired.

5. Planning is shot

After 36 hours without sleep, your ability to plan and coordinate your actions starts to go wrong.

Tests show that this vital ability to decide when and how to start or stop tasks quickly goes awry with lack of sleep.

Sleep deprived people easily get stuck in loops of activity or fogs of indecision.

Either way it’s bad news.

6. Habits take over

Since the sleep deprived find it difficult to make plans or control how they start or stop actions, they have to fall back on the brain’s automated systems.

By which I mean: habits.

Lack of sleep means we rely more on repeating the same actions in the same situations.

Good news when it comes to our good habits, but bad news when it comes to the bad habits.

Hence, the sleep deprived eat more junk food.

7. Risky business

Anyone who has every played a late-night poker session will know the weird effects on your sense of risk.

Studies using card games have found that with lack of sleep, players get stuck in a strategic rut.

They seem incapable of changing their game plan on the basis of experience.

Sleepy people keep taking risks, even though it’s obviously not working for them.

8. Dying brain cells

All sorts of different studies are pointing to how lack of sleep damages brain cells.

One recent study found that in mice 25% of certain brain cells died as a result of a prolonged lack of sleep.

Other studies have found lower integrity white matter in the brain, possibly as a result of lack of sleep.

Just as lack of sleep is no good psychologically, it’s also no good physiologically.

9. Mania

If a person suffers from lack of sleep on a regular basis, they may start to experience mania.

Symptoms include psychosis, paranoia, extremely high energy levels, hallucinations, aggression and more.

Links have been found between insomnia and mental illness. Unfortunately mental illness can also cause poor sleep.

If a person continues to find it difficult to sleep, it can become a vicious circle.

10. Car crash

One of the scary things about lack of sleep is that it can build up over time and then creep up on you.

You miss an hour or two’s sleep each night, but don’t notice that it’s having a detrimental effect.

Studies find that people who are driving with a lack of sleep don’t realise how acute the problem is.

Driving while sleep deprived can actually be worse than driving drunk — it has many of the same effects, but is way less obvious to the driver.

Lack of sleep

The good news is that the cure for most of these deficits is simple: just one good night’s sleep will often do the trick.

After staying awake for 11 days, Randy Gardner reportedly slept for over 14 hours the first night, then 10 hours the next night, thereafter he was fully recovered.

Those must have been some sweet dreams!

Image credit: EdMilson de Lima



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