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Published on: 2/18/2026

The "Old Hag" and Shadow Figures: Why Paralysis Feels So Scary

The Old Hag and shadow figures are classic signs of sleep paralysis, a brief mismatch where your brain wakes while your body remains in REM paralysis, letting dream imagery spill into your real room and triggering a fear response that can feel like an intruder or chest pressure, which is terrifying but usually not dangerous. There are several factors to consider. See below to understand more, including red flags like frequent episodes, daytime sleepiness, dream enactment or injuries that warrant medical care, and practical steps to reduce episodes such as consistent sleep, side sleeping, and calm breathing until it passes.

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Explanation

The "Old Hag" and Shadow Figures: Why Paralysis Feels So Scary

Sleep paralysis — why do I feel a presence during sleep paralysis?

If you've ever woken up and felt unable to move, speak, or cry out — while sensing that someone (or something) is in the room — you are not alone. Across cultures and centuries, people have described the same chilling experience. Some call it the "Old Hag." Others describe shadow figures, dark silhouettes, or an intruder sitting on their chest.

It can feel intensely real. Terrifyingly real.

But here's the important truth: in most cases, this experience is a well-studied neurological event called sleep paralysis. Understanding why it happens can take away much of its power.


What Is Sleep Paralysis?

Sleep paralysis occurs when your brain wakes up, but your body is still temporarily paralyzed from sleep.

During REM (Rapid Eye Movement) sleep, your brain is very active — this is when most vivid dreaming occurs. To protect you from physically acting out your dreams, your brain temporarily turns off your voluntary muscles. This is called REM atonia.

Normally:

  • Your brain and body "wake up" at the same time.

During sleep paralysis:

  • Your brain wakes up first.
  • Your body remains in REM paralysis for seconds to a few minutes.

You are conscious. You can see your room. But you cannot move.

And that's when the fear often starts.


Why Do I Feel a Presence During Sleep Paralysis?

The feeling of a presence is one of the most common and distressing parts of sleep paralysis. Research shows this sensation happens because dream imagery and fear circuits remain active while you are partially awake.

In simple terms:
Your brain is blending dreaming with waking reality.

Here's what is happening neurologically:

1. Your Brain Is Still Dreaming

During REM sleep:

  • The visual and emotional centers of the brain are highly active.
  • The rational, logical parts of the brain are less active.

When you wake up into paralysis:

  • The dream world hasn't fully shut off.
  • Dream imagery can spill into your real bedroom.

This can appear as:

  • Shadow figures
  • A dark presence
  • A person standing in the corner
  • A figure sitting on your chest

These are called hypnopompic hallucinations (if they happen when waking) or hypnagogic hallucinations (if they happen when falling asleep).

They feel real because your visual cortex is firing as if you're still dreaming.


2. Your Threat Detection System Is On High Alert

Another key factor: your brain's fear center, the amygdala, is very active during REM sleep.

When you wake up unable to move:

  • Your brain interprets immobility as danger.
  • Evolutionarily, being unable to move = vulnerability.
  • Your threat system activates instantly.

Your brain asks:
"If I can't move, what is threatening me?"

It may then create a threat to explain the paralysis.

This is why many people report:

  • A sensed intruder
  • A malevolent presence
  • Someone watching them
  • Pressure on the chest

Your brain is trying to make sense of paralysis — and it does so in the most dramatic way possible.


3. Chest Pressure Feels Like an "Old Hag"

Many people report feeling:

  • Something sitting on their chest
  • Difficulty breathing
  • A heavy weight pressing down

Here's why:

During REM sleep:

  • Breathing becomes shallow and automatic.
  • Chest wall muscles are partially relaxed.

When you wake up paralyzed:

  • You may notice shallow breathing.
  • You may feel unable to take a deep breath.
  • Your brain interprets this as "something is sitting on me."

Across cultures, this became folklore:

  • The "Old Hag"
  • Night demons
  • Shadow men
  • Spirit visitations

But medically, it's a combination of:

  • REM muscle paralysis
  • Dream imagery
  • Heightened fear response

Why Does It Feel So Real?

Sleep paralysis hallucinations are often described as more vivid than dreams.

That's because:

  • Your eyes are open.
  • You see your real bedroom.
  • The hallucination is layered on top of reality.
  • You are fully conscious of your fear.

Brain imaging studies show:

  • Emotional centers are highly active.
  • Rational frontal areas are less engaged.
  • Fear responses are amplified.

This combination makes the experience feel intensely authentic.

But it does not mean it is supernatural. And it does not mean you are losing your mind.


How Common Is Sleep Paralysis?

Sleep paralysis is surprisingly common.

Research suggests:

  • Up to 40% of people experience it at least once.
  • It is more common in teens and young adults.
  • It can occur during stress or sleep disruption.

It is more likely if you:

  • Sleep on your back
  • Are sleep deprived
  • Have irregular sleep schedules
  • Experience high stress or anxiety
  • Have narcolepsy

When Should You Be Concerned?

Occasional sleep paralysis is usually harmless.

However, speak to a doctor if:

  • Episodes happen frequently
  • You experience excessive daytime sleepiness
  • You fall asleep suddenly during the day
  • You act out dreams physically
  • You injure yourself or a bed partner during sleep

In some cases, sleep paralysis can overlap with other sleep disorders, including narcolepsy or REM-related conditions.

If you physically act out your dreams, thrash during sleep, or have violent nighttime movements that could injure you or others, this may point to a different condition altogether — and you can quickly assess your symptoms using Ubie's free AI-powered Rapid Eye Movement (REM) Sleep Behavior Disorder symptom checker to help determine whether you should seek medical evaluation.

Always speak to a doctor about symptoms that are severe, worsening, or potentially serious.


Why Sleep Paralysis Feels So Scary — The Honest Truth

It feels scary because:

  • You cannot move.
  • You cannot call for help.
  • Your threat system is activated.
  • Your brain may generate a perceived intruder.
  • Your breathing feels restricted.
  • It happens in the dark, when you are vulnerable.

Your brain is wired to treat immobility as danger.

The fear response is not weakness.
It is biology.

But here's the important perspective:

Sleep paralysis is a temporary state mismatch between brain and body.

It is not:

  • A sign of psychosis
  • A supernatural attack
  • A sign of brain damage
  • A loss of sanity

It is a glitch in the sleep-wake transition.


What Can Reduce Episodes?

Evidence-based strategies include:

Improve Sleep Consistency

  • Go to bed and wake up at the same time daily.
  • Aim for 7–9 hours of sleep.

Reduce Sleep Deprivation

  • Avoid chronic late nights.
  • Prioritize rest during stressful periods.

Manage Stress

  • Relaxation breathing before bed
  • Meditation
  • Gentle stretching
  • Journaling

Adjust Sleep Position

  • Some research suggests sleeping on your side may reduce episodes.

During an Episode

If it happens again:

  • Remind yourself: "This is sleep paralysis. It will pass."
  • Focus on slow breathing.
  • Try moving small muscles (toes or fingers).
  • Avoid fighting it aggressively — that can increase panic.

Most episodes last seconds to two minutes, even if they feel longer.


The Takeaway

If you've asked yourself, "Sleep paralysis — why do I feel a presence during sleep paralysis?", the answer lies in brain science, not superstition.

You are experiencing:

  • REM muscle paralysis
  • Dream imagery blending with reality
  • A temporarily amplified fear response

The shadow figure, the Old Hag, the intruder — these are patterns your brain creates when it wakes up in the wrong phase of sleep.

It feels terrifying because your survival system is activated.

But in most cases, it is not dangerous.

Still, if your symptoms are frequent, worsening, involve violent dream enactment, or significantly disrupt your life, speak to a doctor. Any symptom that could be serious or life threatening deserves medical evaluation.

Sleep paralysis is powerful.
But understanding it gives you power back.

(References)

  • * Denis, D., French, C. C., & Gregory, A. M. (2018). A systematic review of variables associated with sleep paralysis. *Sleep Medicine Reviews*, *38*, 141–157.

  • * Sharpless, B. A. (2016). A comprehensive review of isolated sleep paralysis. *Clinical Psychology Review*, *43*, 126–137.

  • * Jalal, B., & Ramachandran, V. S. (2017). Sleep Paralysis, "The Old Hag" and Out-of-Body Experiences: A Tryptaminergic Hypothesis. *Frontiers in Human Neuroscience*, *11*, 269.

  • * Denis, D., & Gregory, A. M. (2019). The link between stress and sleep paralysis: a systematic review. *Sleep Medicine Reviews*, *43*, 101344.

  • * Solomonova, E. (2020). Sleep Paralysis. *Sleep Medicine Clinics*, *15*(3), 391–402.

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