REM sleep paralyzes the body to stop movement during dreams. Sometimes, that paralysis lasts a little longer after waking up. In this state, people are aware of their surroundings but can’t move or speak.

Hallucinations, chest pressure, and fear often accompany these episodes, making them feel more terrifying than they really should be, given that they are not harmful. While sleep paralysis isn’t dangerous, it can be distressing, especially for those who experience it frequently. Learning what triggers it—and how to prevent it—can make all the difference.

What Is Sleep Paralysis?

Sleep paralysis is a condition where an individual is awake but temporarily unable to move or speak. It occurs during the transition between sleep and wakefulness, either as you’re falling asleep (hypnagogic sleep paralysis) or waking up (hypnopompic sleep paralysis).

  • A common phenomenon: Studies estimate that more than 7% of the general population experiences sleep paralysis at some point in their lives.
  • Short but intense: Episodes can last from a few seconds to a couple of minutes. The intense fear or discomfort makes them feel much longer.
  • Accompanied by vivid hallucinations: Many sense a presence, chest pressure, or footsteps. Hallucinations often link to fears. Culture shapes their form. Personal experiences influence them too.

Sleep paralysis is not a sign of a medical emergency, but it can be distressing. For those who experience it frequently, it may indicate an underlying issue, such as a sleep disorder.

What Happens in the Brain During Sleep Paralysis?

Sleep paralysis happens during specific sleep stages. Sleep alternates between non-rapid eye movement (NREM) and rapid eye movement (REM). Each stage has a unique purpose.

  1. During REM sleep:
    • This is when dreams occur.
    • Your brain is highly active, but your body is paralyzed (a state called atonia) to prevent you from acting out your dreams.
  2. In sleep paralysis:
    • Atonia persists while your brain regains consciousness.
    • You’re mentally awake but physically unable to move or speak.

Brain scans show that sleep paralysis triggers excessive activity in the amygdala, the brain’s fear center. That may be why people feel overwhelming dread during an episode. Hallucinations also happen because the brain misinterprets sensory signals. The combination creates a terrifying but temporary experience.

 Additionally:

  • The reticular activating system (RAS), which controls wakefulness, may wake up prematurely, disrupting the balance between REM and waking states.
  • Sleep deprivation can heighten these effects, as it disrupts the normal sleep cycle and increases the likelihood of REM intrusion during wakefulness.

While these mechanisms are well-documented, the exact neural pathways involved are still a subject of ongoing research.

What Causes Sleep Paralysis?

Experts have linked sleep paralysis to several factors, including sleep disorders, disrupted sleep cycles, and neurological conditions. Here’s what you need to know.

1. Disrupted Sleep Cycles

One of the biggest triggers of sleep paralysis is a messed-up sleep cycle. As mentioned, during REM, your brain prevents your muscles from moving to keep you from acting out dreams. REM atonia is temporary paralysis that is normal. But with sleep paralysis, your brain wakes up before your body does, leaving you conscious but unable to move.

  • Why it happens: Irregular sleep patterns throw off the body’s ability to transition smoothly between sleep stages. This can be caused by shift work, jet lag, or chronic sleep deprivation.

2. Sleep Disorders like Narcolepsy

Narcolepsy disrupts REM sleep and raises the risk of sleep paralysis. Excessive daytime sleepiness is common. Sudden sleep episodes often lead straight into REM. Quick REM entry makes paralysis more likely. Narcoleptics face this risk more than others.

  • Why it happens: The brain struggles to regulate sleep-wake cycles, making it easier for paralysis to occur at the wrong time.
  • Who’s at risk? Studies show that up to 50% of people with narcolepsy have sleep paralysis episodes.

3. Mental Health Conditions (Anxiety, PTSD, and Depression)

Anxiety, PTSD, and depression often go hand in hand with sleep paralysis. Stress throws off sleep patterns, making it difficult for the brain to transition between stages. Sudden awakenings during REM sleep can leave a person temporarily paralyzed. PTSD increases the risk, especially when nightmares trigger abrupt wake-ups. The brain struggles to shake off REM paralysis, creating a frightening experience.

  • Why it happens: Chronic stress and trauma affect the brain’s ability to regulate REM sleep.
  • Research-backed connection: A study found that 31.9% of psychiatric patients reported experiencing sleep paralysis compared to only 7.6% of the general population.

4. Sleeping Position (Especially Sleeping on Your Back)

Believe it or not, the way you sleep can trigger sleep paralysis. Studies have found that sleeping on your back increases the likelihood of an episode. This position can lead to airway obstruction, shallow breathing, and reduced blood circulation, all of which contribute to disrupted REM sleep.

  • Why it happens: Lying on your back can cause breathing difficulties, triggering micro-awakenings during REM sleep. These awakenings may bring consciousness before muscle control is restored.

5. Neurological Conditions and Genetics

Certain neurological conditions, such as migraines and epilepsy, have been linked to sleep paralysis. Some research also suggests a genetic component—if someone in your family experiences sleep paralysis, you might be more likely to have it too.

  • Why it happens: Brain structures that control sleep and wakefulness may be slightly different in people with neurological conditions. Genetics may also play a role in how the brain transitions in and out of REM sleep.

What Are the Symptoms of Sleep Paralysis?

Sleep paralysis can be unsettling, but understanding its symptoms can help demystify the experience. It typically occurs during the transition between sleep and wakefulness and is often accompanied by distinct signs:

1. Inability to Move or Speak

  • The most defining symptom.
  • Individuals remain fully aware but cannot move their body or vocalize.
  • This temporary paralysis usually lasts a few seconds to a couple of minutes.

2. Hallucinations

  • Visual: Shadows, figures, or even detailed entities that may feel threatening.
  • Auditory: Sounds such as footsteps, whispers, or even loud bangs.
  • Tactile: Sensations like being touched, pressed down upon, or even floating.

3. Feeling of Pressure

  • A common sensation is heaviness on the chest, sometimes described as a crushing weight.

4. Fear or Panic

  • The inability to move, paired with vivid hallucinations, often triggers intense fear.
  • Many report feeling as though they are in imminent danger.

5. Recurring Episodes

  • Some individuals experience sleep paralysis sporadically, while others have frequent episodes, especially during periods of stress or sleep disruption.

While these symptoms are distressing, they are not harmful on their own and usually resolve without intervention.

Is Sleep Paralysis Dangerous?

Sleep paralysis is not physically harmful. However, the psychological impact can be significant.

Why It’s Not Physically Dangerous

  • It’s a natural phenomenon related to the REM stage of sleep.
  • No long-term physical damage results from episodes.

Why It Feels Threatening

  • The hallucinations, paired with immobility, can mimic life-threatening situations.
  • Some individuals with sleep paralysis report a sense of an “evil presence” during episodes.

Psychological Impacts

  • Chronic episodes can lead to anxiety about sleeping.
  • Some individuals develop insomnia or other sleep-related issues due to fear of recurrence.
  • Those with a history of trauma or PTSD may experience heightened distress during episodes.

While sleep paralysis itself isn’t dangerous, its emotional toll can disrupt overall sleep quality and well-being.

How Can You Prevent Sleep Paralysis?

Although you can’t entirely eliminate sleep paralysis, there are practical strategies to reduce its frequency and severity.

1. Improve Sleep Hygiene

  • Aim for 7–9 hours of quality sleep per night.
  • Go to bed and wake up at the same time daily to regulate your internal clock.
  • Avoid screens at least an hour before bed, as blue light disrupts melatonin production.

2. Reduce Stress

  • Stress is a major trigger for sleep disturbances, including sleep paralysis.
  • Practice relaxation techniques such as meditation, deep breathing, or progressive muscle relaxation before bedtime.

3. Limit Stimulants

  • Avoid caffeine, nicotine, and alcohol in the hours leading up to bedtime.
  • These substances disrupt the natural sleep cycle, increasing the likelihood of fragmented sleep.

4. Adjust Sleeping Position

  • Sleeping on your back is associated with a higher risk of sleep paralysis.
  • Try sleeping on your side to reduce susceptibility.

5. Treat Underlying Sleep Disorders

  • Conditions like obstructive sleep apnea (OSA) or narcolepsy can exacerbate sleep paralysis.
  • Seek professional diagnosis and treatment for persistent sleep disturbances.

6. Adopt a Pre-Bedtime Routine

  • Incorporate calming activities such as reading or taking a warm bath before bed.
  • Avoid high-intensity workouts or emotionally charged activities right before sleep.

These preventive measures not only reduce the risk of sleep paralysis but also improve overall sleep quality.

When Should You Seek Professional Help?

Occasional sleep paralysis is common and harmless. But, frequent or distressing episodes may need attention. A sleep specialist can help.

1. Frequent Episodes

  • If episodes occur more than a few times per month, they may indicate an underlying issue such as narcolepsy.

2. Severe Emotional Distress

  • Persistent fear, anxiety, or sleep avoidance due to sleep paralysis impacts mental health and daily functioning.

3. Signs of a Sleep Disorder

  • Symptoms like loud snoring, choking or gasping during sleep, or excessive daytime sleepiness may point to obstructive sleep apnea or another sleep disorder.

4. Impact on Daily Life

  • Difficulty concentrating, irritability, or reduced productivity due to poor sleep quality should not be ignored.

What a Sleep Specialist Can Do:

  • Run a detailed sleep test to figure out what’s causing your sleep issues.
  • Recommend proven treatments, like therapy for insomnia (CBT-I), CPAP machines for sleep apnea, or medication if needed.

Getting expert help can improve sleep paralysis and make sure you’re getting the best rest possible.

References

Sharpless, B. A., & Barber, J. P. (2011). Lifetime prevalence rates of sleep paralysis: A systematic review. Sleep Medicine Reviews, 15(5), 311–315. https://doi.org/10.1016/j.smrv.2011.01.007

‌Disclaimer: This information is for general knowledge only. Please consult a doctor for medical advice.