What You Should Know About Microsleep

Ever realize you don’t quite remember the last few seconds of a drive? Or been rocking your baby to sleep and felt like you jumped forward in time by just a few ticks of the clock?

Those moments could be more than just a simple distraction. They may be episodes of microsleep — and when they happen at the wrong time, things can get bad, quick.

We talked with sleep medicine specialist Samuel Gurevich, MD, about what microsleep is and how it can affect you.

What is microsleep?

Microsleep is a very brief episode of involuntary sleep that happens when you’re extremely tired. It typically lasts 30 seconds or fewer, and you may not even realize you’ve nodded off.

During those few seconds, your eyes may stay open, but your brain essentially checks out.

“The longer you’ve been awake, the stronger your brain’s drive to sleep becomes,” Dr. Gurevich explains. “Eventually, it may try to make you sleep, even if you’re working hard to stay awake.”

Causes

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Microsleep is usually your brain’s way of telling you it desperately needs rest. Common causes of microsleep include:

• Sleep deprivation: This is the most common cause. The longer you’re awake, the more likely your brain is to attempt to force sleep. If you’re consistently not getting enough quality sleep, you can become vulnerable to microsleep and other effects.
• Working overnight or rotating shifts: Shift work can disrupt your body’s natural sleep-wake cycle, making microsleep more likely.
• Sleep disorders: Conditions like sleep apnea and insomnia can leave you chronically sleep-deprived. A fitful night doesn’t give you the quality rest your brain and body need.
• Alcohol: Drinking alcohol can make you drowsy and increase your risk of falling asleep unexpectedly.
• Certain medications: Antihistamines, sleeping pills and other medications with sedative effects can trigger microsleep episodes.

Is microsleep dangerous?

Microsleep itself isn’t necessarily harmful, but what happens during those few seconds can be.

“When your brain is trying to proactively put you to sleep, it can happen in dangerous situations,” Dr. Gurevich says. “Sleepiness causes a significant number of car and industrial accidents.”

Think about it: At highway speeds, your car can travel the length of a football field in just a few seconds. If you experience microsleep behind the wheel, you could drift into another lane, miss traffic signals or fail to react to changing road conditions during those few seconds.

“If you’re tired while driving, find a safe place to pull over to take a short nap to refresh yourself,” he advises. “Even better, don’t drive if you’re sleep-deprived. Catch up on your sleep first.”

Microsleep can also be dangerous if you:

• Operate heavy machinery
• Work at heights
• Use power tools
• Perform jobs that require constant vigilance

And beyond the immediate danger, sleep deprivation over time can have severe effects on your well-being.

“In the long-term, insufficient rest can increase your risk for cardiovascular disease, stroke and mood disorders, like depression and anxiety,” Dr. Gurevich says.

Microsleep symptoms

Because microsleep comes and goes so quickly, you may not realize it happens. But your body often gives you warning signs that you’re becoming dangerously sleepy.

Symptoms of an oncoming microsleep episode may include:

• Frequent or slow blinking
• Excessive yawning
• Difficulty concentrating or understanding information

Treatment

Treating microsleep starts with identifying why it’s happening. A healthcare provider can help to get to the root of the problem by:

• Reviewing your medications to see if one is causing drowsiness
• Evaluating you for an underlying sleep disorder, like sleep apnea
• Checking for medical conditions that can contribute to excessive sleepiness, including anemia, thyroid disease and heart failure.

Once the underlying cause is addressed, microsleep episodes often improve.

How to prevent microsleep

The best way to prevent microsleep is to get enough high-quality sleep regularly. Dr. Gurevich offers these tips to keep your body and mind rested and ready for whatever the day brings:

• Aim for seven to nine hours of quality sleep each night.
• Don’t try to “push through” overwhelming sleepiness.
• Take a short nap if you feel excessively tired.
• Avoid alcohol before activities that require you to stay alert.
• Use caution with medications that can cause drowsiness.
• Don’t rely on caffeine to overcome severe sleep deprivation.

“Getting enough good-quality sleep is really important for your total health,” Dr. Gurevich emphasizes. “If you feel more tired and less energetic than you used to, check in with your healthcare provider.”

Final thoughts

Microsleep may only last a few seconds, but it can be enough to change your life if it happens at the wrong time.

Don’t ignore the warning signs. They may be your body’s way of telling you it’s time to prioritize sleep — or to talk with a healthcare provider about an underlying problem.