Sleep Paralysis: What It Is, Why It Happens and What Helps

Short answer

Sleep paralysis happens when you partly wake up during REM sleep, the stage of most vivid dreaming, while that stage’s natural muscle relaxation is still switched on. Your mind is aware of the room, but for a few seconds or minutes your body will not move.

It can be frightening, especially the first time, but for most people it is harmless and passes on its own. Dream imagery can spill into that half-awake moment, which is why it sometimes comes with strange sounds, shapes or the feeling that someone is there.

Why it happens and what helps

During REM sleep the brain keeps most of your muscles relaxed, a state called atonia, so you don’t act out your dreams. Sleep paralysis is a brief mismatch in that timing: awareness returns before the body is released. It tends to show up more often after sleep deprivation, with an irregular schedule, jet lag or shift work, in stressful periods, and for many people when sleeping on their back.

If it happens, reminding yourself “this is sleep paralysis and it will pass” takes away much of the fear. Breathe slowly and try moving something small, like a finger or a toe, instead of fighting your whole body. Over time, regular sleep hours and enough rest tend to make episodes less common. If it happens often, disturbs your sleep or comes with heavy daytime sleepiness, it is worth talking to a doctor or sleep specialist.

Common scenarios

• Sensing a presence in the room: one of the most common features, often felt as someone standing nearby or watching. It is usually understood as the brain’s alarm system misfiring in a half-dreaming state.
• Pressure on the chest: a heavy, pressed-down feeling. Your breathing keeps working on its own during REM, even if fear makes it feel restricted.
• Seeing a dark figure or shadow: dream images laid over your real bedroom, known as hypnopompic hallucinations when they happen on waking.
• Hearing buzzing, footsteps or voices: sound hallucinations are also common and fade as you fully wake.
• Happening as you fall asleep: episodes can come at sleep onset too, especially when you are very overtired.
• Floating or out-of-body feelings: reported by some people, and a starting point some use for lucid dreaming.
• Several episodes in a hard month: usually a sign that sleep has become short or irregular, not that something is wrong with you.

Questions to ask yourself

• Was I sleeping less, or at odd hours, in the days before it happened?
• What has been weighing on me lately that could be making my sleep lighter?
• What did the presence feel like, and does that feeling show up anywhere in my waking life?
• Would a short note after each episode help me spot a pattern?

Frequently asked questions