Hypnagogic Hallucinations

What are hypnagogic hallucinations?

Hypnagogic hallucinations are hallucinations that happen as you’re falling asleep. They’re common and usually not a cause for concern. Up to 70% of people experience them at least once.

A hallucination is a false perception of objects or events involving your senses: sight, sound, smell, touch and taste. Hallucinations seem real but they’re not.

Hypnagogic hallucinations are usually brief and fleeting, but are occasionally prolonged. They can take different forms, including:

• Visual (seeing something that’s not there): About 86% of hypnagogic hallucinations are visual and usually consist of changing geometric patterns, shapes and light flashes. It may seem like you’re looking into a kaleidoscope. They may also involve images of animals, people or faces.
• Somatic (feeling or sensing something that’s not real): About 25% to 44% of hypnagogic hallucinations are somatic experiences. They may involve feeling bodily distortions; feelings of weightlessness, flying or falling; and sensing the presence of another person in the room.
• Auditory (hearing something that’s not there): About 8% to 34% of hypnagogic hallucinations are auditory — either hearing sounds or voices. They may involve words or names, people talking, and environmental or animal sounds.

While hypnagogic hallucinations are a common symptom of narcolepsy, they also occur in people who don’t have narcolepsy.

If you experience hallucinations during the day or night when you’re wide awake in addition to hypnagogic hallucinations, it may be a sign of a mental health disorder or neurological condition.

What’s the difference between hypnagogic and hypnopompic hallucinations?

Hypnagogic and hypnopompic hallucinations are both sleep-related hallucinations. Hypnagogic hallucinations happen as you’re falling asleep and hypnopompic hallucinations happen as you’re waking up. Both types aren’t usually a cause for concern.

What’s the difference between a hypnagogic hallucination and a dream?

It can be easy to confuse a hypnagogic hallucination with a dream, but they’re different.

You can tell the difference because dreams typically have a storyline, whereas hypnagogic hallucinations are typically brief images or sounds.

In addition, you’ll likely know instantly when you wake up from a dream or nightmare that you were just dreaming but aren’t anymore. Hypnagogic hallucinations happen while you’re still awake — albeit almost asleep — and it may take some time to figure out what’s real and what isn’t.

What causes hypnagogic hallucinations?

Researchers aren’t sure what exactly causes hypnagogic hallucinations. But they seem neurologically similar to both daytime hallucinations and dreams.

For most people, hypnagogic hallucinations aren’t associated with a health condition and are considered harmless. However, hypnagogic hallucinations are more common in people with certain sleep disorders and health conditions, including:

• Narcolepsy.
• Insomnia.
• Excessive daytime sleepiness.
• Mental health disorders.

People who take tricyclic antidepressants are also more likely to experience hypnagogic hallucinations.

Can anxiety cause hypnagogic hallucinations?

Anxiety typically doesn’t cause hypnagogic hallucinations, but experiencing hypnagogic hallucinations frequently, especially if you find them disturbing, can cause anxiety or sleep anxiety.

If hypnagogic hallucinations are causing you distress, you should talk to a healthcare provider.

Should I be concerned if I have hypnagogic hallucinations?

Although having a hallucination as you fall asleep might make you feel confused or scared, hypnagogic hallucinations are relatively common and likely not something to worry about.

It’s important to know that hypnagogic hallucinations are different from hallucinations associated with mental health conditions, like schizophrenia, and neurological conditions, such as Alzheimer’s disease and Parkinson’s disease.

People with these conditions experience hallucinations during the day when they’re wide awake and have other significant signs and symptoms of the condition.

Can I do anything to make hypnagogic hallucinations go away?

Hypnagogic hallucinations may or may not need treatment. They may decrease in frequency if you do the following:

• Get enough quality sleep.
• Follow a regular sleep schedule.
• Avoid alcohol and certain drugs and medications.

If the hallucinations are causing you distress or anxiety, it’s important to talk to a healthcare provider. They may prescribe medications to help you or change any current medications you may be taking that could be causing the hallucinations.

A healthcare provider can also determine if the hypnagogic hallucinations are a sign of a health condition, such as narcolepsy. If so, the underlying condition will need treatment.