Microsleep refers to periods of sleep that last from a few to several seconds. People who experience these episodes may doze off without realizing it. Some may have an episode in the middle of performing an important task.

It can occur anywhere, such as at work, at school, or while watching TV. Episodes of microsleep can also happen while driving or operating machinery, which makes this a dangerous condition.

Microsleep can be difficult to identify because you may nod off while your eyes are starting to close. Symptoms associated with this condition include:

  • not responding to information
  • a blank stare
  • dropping your head
  • experiencing sudden body jerks
  • unable to remember the last one or two minutes
  • slow blinking

Warning signs of an episode of microsleep include:

  • an inability to keep eyes open
  • excessive yawning
  • body jerks
  • constantly blinking to stay awake

Episodes can occur at times of the day when you normally sleep. This can include early morning hours and late at night. However, microsleep episodes aren’t limited to these times of the day. They can happen anytime you’re sleep-deprived.

Sleep deprivation can be a chronic or acute condition in which you don’t get enough sleep. About 1 in 5 adults are sleep-deprived, which often results in:

Lack of sleep has also been linked to:

A lack of sleep is a risk factor for microsleep. This can happen if you have insomnia, work a night shift, or don’t get enough quality sleep for other reasons. You may also experience microsleep if you have a sleep disorder:

  • With obstructive sleep apnea, a blockage in your upper airway interrupts breathing while sleeping. As a result, your brain doesn’t receive enough oxygen during sleep, which can trigger daytime sleepiness.
  • Narcolepsy causes extreme daytime drowsiness and intermittent uncontrollable episodes of falling asleep.

The exact cause of microsleep isn’t fully understood, but it’s believed to happen when parts of the brain fall asleep while other parts of the brain remain awake.

In a 2011 study, researchers kept lab rats awake for an extended period of time. They inserted probes into neurons affecting their motor cortex while using an electroencephalogram (EEG) to record their brain’s electrical activity.

Even though EEG results indicated that the sleep-deprived rats were fully awake, the probes revealed areas of local sleep. These findings have led researchers to believe that it’s possible for humans to experience brief episodes of local sleep in the brain while appearing awake.

To treat and prevent episodes of microsleep, it’s important that you get enough sleep at night. A healthy amount of sleep for adults can range from seven to nine hours.

Making a few lifestyle adjustments and developing a sleep routine may improve the quality of your sleep. These may include:

  • avoiding caffeine and liquids before bed, especially alcohol if you’re already tired
  • turning off any surrounding lights or sounds
  • avoiding stimulating activities before bed
  • keeping your bedroom at a comfortable temperature

While driving

To keep yourself safe while driving, only operate a vehicle when you’re feeling alert. It also helps to drive with a companion who can take over driving if you become drowsy.

Signs that you need to pull over include:

  • drifting out of your lane
  • repeated yawning
  • missing exits
  • heavy eyelids

In addition, keep your mind engaged while driving to stay alert. Listen to music with a fast tempo or play an audiobook or a podcast.

At work

While you’re at work, don’t operate any equipment or machinery when you’re feeling drowsy or sleepy. This can lead to an accident or injury. Participate in conversations and discussions to remain alert and attentive.

If possible, periodically get up from your chair or desk and stretch your legs. Being physically active can wake up your body and fight sleepiness.

If you make lifestyle adjustments but still experience episodes of microsleep or feel sleep-deprived, see a doctor. You may need a sleep study to confirm or rule out a sleep disorder. Understanding the underlying cause of sleep deprivation may prevent future episodes of microsleep.

According to the AAA Foundation for Traffic Safety, it’s estimated that 16.5 percent of fatal crashes on the nation’s roadways involve a drowsy driver.

Sleep deprivation is a serious problem because it can impair judgment and reduce your reaction time while driving. Increasing the quality or quantity of your sleep may provide long-term relief. But if you’re caught in a situation where you’re tired and don’t have a driving companion, pull over to a safe location and take a 30-minute power nap.

Another option is consuming about 75 to 150 milligrams of caffeine to increase mental alertness and fight off drowsiness. Keep in mind, however, that caffeine is a stimulant, and having too much over a prolonged timeframe can lead to tolerance.

After a long period of too much caffeine use, if you suddenly reduce or stop taking caffeine, you can have unpleasant withdrawal symptoms. You shouldn’t rely on caffeine on a regular basis to try to overcome fatigue.

Microsleep can be a dangerous condition, so learn how to identify signs and symptoms of this condition in yourself and others.

Improving the quality of your sleep not only stops you from falling asleep at the wrong place and time, but also contributes to better health. An adequate amount of sleep can improve your energy level, mood, and concentration, while reducing your risk for health problems.