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Sleep quality does not depend entirely on total sleep time. Sleep disturbances, for instance, can create an overall condition known as sleep fragmentation, which leads to poor sleep. You can learn to overcome sleep fragmentation by developing good sleep habits.



Matthew Walker Teaches the Science of Better SleepMatthew Walker Teaches the Science of Better Sleep

Neuroscience professor Matthew Walker teaches you the science of sleep and how to optimize it to better your overall health.

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What Is Sleep Fragmentation?

Sleep fragmentation is the interruption of nocturnal sleep. Arousals during your sleep cycle throw off your natural circadian rhythms, leading to sleep disruption and overall poor sleep. Sleep fragmentation and the resultant sleep loss can lead to significant differences in your waking functions.

Why Is Understanding Sleep Fragmentation Important?

Sleep fragmentation can cause cognitive impairment, excessive daytime sleepiness, and even diminished life expectancy—so it’s important to your health that you learn to overcome it. Overly tired people with sleep dysfunction can harm other people when performing their jobs, while driving, or while supervising vulnerable people.

How Do Scientists Track Sleep Fragmentation?

In studies of sleep disorders, neuroscience researchers subject their patients to overnight polysomnographic evaluation to gauge the effect of fragmented sleep. Through the use of electromyographic (EMG) electrodes, polysomnography records sleep latency (how long it takes to fall asleep), cardiovascular activity, blood oxygen metrics, periodic limb movements, and cortical brain activity. This helps neuroscientists track the stages in the sleep-wake cycle, including light sleep, rapid eye movement (REM sleep), and deep sleep. When sleep fragmentation interrupts any of these sleep stages—particularly REM sleep and deep sleep—it can lead to adverse mental and physical effects.

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7 Causes of Interrupted Sleep

Neuroscientists believe that sleep fragmentation, along with insufficient sleep duration, can be traced to a number of causes:

  1. Obstructive sleep apnea syndrome or other sleep-disordered breathing issues that affect airflow
  2. Excessive snoring that rouses one into wakefulness
  3. Periodic leg movements
  4. Alcohol and drugs, including some sleep medicine
  5. Itching and scratching
  6. Anxiety and stress
  7. Inconsistent sleep patterns brought on by daytime sleep

4 Potential Effects of Interrupted Sleep

Sleep fragmentation and general sleep deprivation can affect your mental and physical health, both in the short-term and over long periods of time. Problems related to poor sleep efficiency include:

  1. Daytime drowsiness: A poorly rested person can go through the day feeling groggy. This can lead to drowsy driving, car accidents, mental slip-ups, and poor cognition.
  2. Microsleep: In addition to general drowsiness, a person running on very little sleep can experience microsleep—very short bursts of unconsciousness that feel like blacking out.
  3. Mood swings: A person overcome by sleepiness may be cranky and irritable, and they may also experience headaches that further sour their mood.
  4. Memory issues: Poor sleep patterns that cause a person to get less sleep have the potential to affect memory recall.


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4 Tips for Avoiding Interrupted Sleep

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Neuroscience professor Matthew Walker teaches you the science of sleep and how to optimize it to better your overall health.

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To avoid sleep fragmentation in your own life, consider the following steps:

  1. Stick to a routine. You can avoid sleep fragmentation by keeping a strict schedule for falling asleep and waking up. Allow yourself a full eight hours to sleep (or more if your schedule allows it). Do not alter your routine on weekends; your body responds best to consistency.
  2. Avoid drinking and using drugs before bed. Many drugs impair sleep cycles thanks to their activation of wakeful chemicals in the body. Alcohol can make you sleepy, but it often leads to restless sleep.
  3. Use sleep medications sparing. Many sleep medications can make you fall asleep, but they produce low-quality sleep. A fully restorative night includes both REM sleep and deep sleep, and some over-the-counter drugs impair these stages of the sleep-wake cycle. Melatonin, which is naturally produced by the body, can be conducive to deep sleep when taken as a supplement.
  4. Keep digital devices away from your bed. The glow of blue light and the stimulation of computer and smartphone use can keep your brain from winding down into a sleep cycle. To improve sleep quality, consider moving electronic screens out of your bedroom entirely.

Want to Learn More About Catching Those Elusive Zs?

Saw some of the best darn logs of your life with a MasterClass Annual Membership and exclusive instructional videos from Dr. Matthew Walker, the author of Why We Sleep and the founder-director of the Center for Human Sleep Science at the University of California, Berkeley. Between Matthew’s tips for optimal snoozing and info on discovering your body’s ideal rhythms, you’ll be sleeping more deeply in no time.