Hypnagogic Hallucinations: Things That Go Bump In The Night

geometric shapes image demonstrating hypnagogic hallucinations

Have you ever seen something like this in the dark at night?

Have you ever switched off the bedside light, only to suddenly see strange shapes, animals or figures in the darkness? Perhaps you’ve heard voices or sounds which can’t possibly be real?

If so, it could be that you’ve experienced what’s known as a sleep hallucination, also sometimes referred to as hypnagogic hallucinations.

Many people experience hypnagogic hallucinations at some point in their lives, sometimes on a regular basis. And I’m no exception.

As a child I’d often see strange, multicolored geometric shapes in the darkness when trying to sleep. I used to lie there alternating between marveling at them and wishing them away so I could sleep in peace.

It doesn’t happen so often nowadays, but once in a while I’m still prone to these mathematical manifestations. Perhaps I should be grateful for my geeky hypnagogic hallucinations. Especially compared to the disturbing experiences that some people have.

So what exactly is this strange phenomenon and why does it happen? In this article I’ll be taking a closer look to help you understand what you’ve experienced yourself.


hypnagogic hallucinations occur when falling asleep, hypnopompic when waking upHypnagogic hallucinations are usually short-lasting experiences in which you might see, hear or feel something which isn’t real whilst transitioning from being awake to asleep.

It can be an auditory, sensory, tactile or any other sensory experience. Whatever form it takes though, it’s not real and is caused by your amazingly creative brain.

Hypnopompic hallucinations are exactly the same thing, except that they occur while you’re waking from sleep. For the sake of simplicity I’ll refer to the phenomenon as hypagogic hallucination throughout this article.

Both hypnagogic and hypnopompic hallucinations can be very vivid, so can be disturbing in some cases. Especially if you see creatures appearing in your room, voices saying unpleasant things or feeling something touch you.

The history

Hypnagogic hallucinations were first described in 1664 by the Dutch Physician Isbrand Van Diemerbroeck. He might not have called it by the name we know it as today, but he did describe a woman who appears to have experienced hypnagogic hallucinations.

How many people experience it?

up to one third of people experience hypnagogic hallucinations in their lifetimeThere hasn’t been much research done to find out how many people experience this. But the following surveys and research show how common it might be:

1. A telephone survey in the United Kingdom in 1996 of 4972 people found that 37% experienced hypnagogic hallucinations twice a week or more.

Furthermore, 12.5% experienced hypnopompic hallucinations. It was more common among people with insomnia, excessive daytime sleepiness and mental illness.

2. A review of 35 different studies in 2011 found that 7.6% of people experience sleep paralysis in their lifetime. We’ll see later how sleep paralysis often occurs alongside hypnagogic hallucinations.

3. In 2000 a survey of 13,000 people found that 38.7% experienced hallucinations, though 27% were in the daytime. 2.7% of people had them once a week, with 2.4% more than once a week.

So you can see that if you do experience hypnagogic hallucinations, you’re definitely not alone!

Symptoms of hypnagogic hallucinations

It’s possible to experience hallucinations that correspond to any of your senses, though visual hallucinations are the most common. They can be experienced from between just a few seconds to a few minutes:

  • Visual – for example the geometric shapes in the picture above. But possibly also images of people, animals or other complex shapes.
  • Auditory – this can be simple sounds like hissing, humming or whistling. But it can also be more complex sounds like human voices. It may also be extremely loud, similar to the sleep disorder known as exploding head syndrome.
  • Olfactory – perceiving smells which aren’t actually there, either pleasant or unpleasant.
  • Tactile – this can be very disturbing, such as feeling insects or spiders crawling on the skin. It can also be a strange rubbing, stroking, tapping or tickling sensation.

Furthermore, there can be more complex hallucinations as part of sleep disorders such as sleep paralysis. You may feel unable to move your body, and perhaps see or sense a person or presence in the room.


The latest international classification of sleep disorders manual in 2014 presents the following 2 main causes, though does state more research is needed to confirm them:

  • An intrusion of dream imagery onto wakefulness.
  • A lack of stimulus leading to the visual cortex in the brain creating images.

The causes of sleep hallucinations may also be related to another illness or sleep disorder. For example, they’re often associated with these sleep disorders:

  • Narcolepsy.
  • Sleep paralysis.
  • Exploding head syndrome.
  • Excessive daytime sleepiness.
  • Sleep terrors.

They can also be associated with a mental illness such as Schizophrenia. Each of the above will have a particular way of explaining the causes that’s relevant to them.

In addition there are some things which might lead to an increase in frequency or intensity of hallucinations, including:

  • Stress.
  • Sleep deprivation or exhaustion.
  • Electrical activity in the brain.
  • Drugs – particularly illegal drugs such as hallucinogenics, ecstasy and marijuana. But also some medical drugs, including sleeping pills.
  • Brain damage or lesions.


relaxing can help reduce stress and prevent hallcuinationsA doctor would want to rule out any of the other illnesses or sleep disorders first, particularly narcolepsy and schizophrenia.

If you do have one of those, then your treatment would be tailored accordingly.

For example, Schizophrenia is usually treated with anti-psychotic medication. Narcolepsy will be treated with advice about lifestyle changes and possibly medication.

For most people, however, there’s no specific treatment for hypnagogic hallucinations and reassurance is the main need. It’s something which you just need to accept as a normal part of life.

Despite that, there are lifestyle choices you can make which may help. And the same applies to those who experience them as part of another sleep disorder. Here are some ideas which may help keep the hallucinations at bay:

  • Get an adequate amount of sleep every night, follow a stable sleep schedule and don’t allow yourself to become sleep deprived.
  • Avoid illegal drugs and check with a doctor if any medication you’re taking may be causing it.
  • Eat a healthy diet and drink plenty of water.
  • Try to reduce your stress levels.
  • Try using a soft night light in the bedroom. This might help fill the space that your brain uses as a blank canvas.
  • If you tend to hear things, perhaps listening to music or the radio at night will help.
  • If you find yourself focusing on visual hallucinations, try to re-focus your mind on something else. So for example, breathing exercises or muscle relaxation can keep your brain occupied.
  • If it’s overwhelming, turn on a light and get up for a while, do something relaxing and then try to sleep again after 10-15 minutes.
  • Several readers have said in the comments below that wearing a sleep mask helps them.

Generally though, you can see that hypnagogic and hypnopompic hallucinations are a normal part of life for many people. Once you’ve ruled out any serious illness or disorder, then you’re left to deal with the experience in two ways.

First, try to adapt your lifestyle to make sure you do everything possible to sleep well. Second, relax and try not to worry about things that go bump in the night.

If you do find yourself becoming overwhelmed by your experiences, it might help to talk to your doctor for some reassurance. You may also find it helpful to try some relaxation techniques which can help take your mind off any hallucinations.

Your thoughts

Do you ever experience hallucinations when falling asleep or waking up? What form do they take?

Do you find they get worse at certain points in your life, or if you do certain things? Have you found anything which helps prevent them?

Feel free to describe your experience in the comments below and share any ideas you have about dealing with them.

Please note that after years of responding to comments personally, I’ve now decided to leave this discussion entirely to readers.

I will still read your comment before publishing it, but would like to leave the fantastic discussion that has grown here over the years in your hands now.

844 CommentsLeave a comment

  • I’m a 20 year old man who has been having this problem my whole life. At first every night, then spaced, and then they went away. However tonight it happened again…never do you ever get to see the things and feel the emotions you feel when these hallucinations happen. Its both a blessing and a curse, but i think mostly a blessing

  • I have experienced this many times in the past. Not very frequently anymore. The most resent one I experience was when i was sleeping at my boyfriends appartment but I was alone he was at work. I woke up and it was very bright outside. I couldnt move but I could open my eyes. I felt the bed moving as if someone was crawling onto the bed. I then felt like someone grabbed my hand and was just gently holding it. very shortly after I was able to move, looked around and there was no one there. Have also had very intense auditory hallusinations where I am not asleep at all but trying to fall asleep. one time I could hear a jumble of voices all talking at once. it would go away if I opened my eyes but everytime I closed my eyes to try to sleep it would instantly start again.

  • I’m experiencing hypnagogic hallucinations more and more regularly. I used to have them every couple of weeks but now I have them almost every night. I see people mainly, who are always dressed in old fashioned clothes but also creatures swarming through holes in the ceiling and lots of other really stupid things (like chickens under the bed!). I’ve possibly linked this problem to the contraceptive pill, but I’m still researching this. I’d like to know if there’s any more I can do to get rid of these for good, I feel like a zombie most of the time!

  • This helps me, I thought I was crazy because for all my life I’ve seen my dead cat whenever I turn lights off or close my eyes.

  • I have this issue. If I have hypnagogic hallucinations it’s almost always seeing a spider (which means jumping up in fear, freaking my bed partner out), though sometimes it involves a sound or a physical feeling.

    I have no idea if it’s related, but sometimes I wake up only slightly (not enough to move, but aware) and have all these thoughts that don’t make sense. Like I’ll be thinking “It’s okay if the elephant wears pink, because the pinecones are shaking.” What does that even mean? I’m awake but it’s as though my brain is messed up. Sometimes I’m even aware while thinking it that it makes no sense, but it’s like my brain believes it to be true. Does that even make sense? Does anyone know what I’m talking about?

  • I’m a 63 year old female and feel relieved with this explanation. I will follow up with my Dr. Last night was the worst and the best. Beautiful images of fluttering birds and butterflies but this lasted for several hours the room also seemed to have been painted with glitter. When I touched my comforter it would light up under my fingers. Towards morning people were appearing. The most disturbing was the damn music! I have checked out some medical conditions this seems to be the best option possible. Thank you

  • I remember as I was younger I had something very similar to sleep pyralysis, but sometimes when I experienced it I could still move my arms and eyes. I would put my arms over my face so I couldn’t see because it was very scary. I would see a black figure that floated above my bed on the wall for a few seconds then i would close my eyes real fast and when i opened them the black figure would be in my face as it was screaming but i heard a loud pitch almost buzzing sound and it was extremely scary and I did feel like I had pressure on my body but could still move and made me feel terrified. Another thing that also happened is I was in the middle of having a dream and my friend woke me up and I immetialy had that scared terrified feeling and saw a black figure behind her just covered my eyes real fast because i was scared to see it and it felt real I had said there is something behind you, which scared her but im wondering what that could have been if you can’t move in sleep pyralysis

  • I sleep in a very dark room and also wear eye blinders. Total darkness. I was near morning and I could see a TV screen with people on it. An old TV. black and white. I could have watched the whole thing but I woke myself up. Very strange.

  • I am 44 year old male. Who just recently have been experiencing visions, when I wake up. It only happens when the room is dark. If there is a light on, they either vanish before my eyes or don’t show up.
    Its been insects, like Beatles or some type of bug with about 8 legs, crawling on the ceiling or wall. If I see them manifest themselves, I will turn the light on my phone and it goes away. Most of the time, I just get mad and go to sleep. I just think to myself, they are not real and cannot hurt you. I started taking Clonidine before I go to bed and it only seemed to happen when I started this medication. But, I do take meds in morning and before I go to sleep. This just freaks me out, never had anything like this happen to me before and it seems so real. Any advice would be welcomed.

  • This started to happen to me when I moved into my college dorm. At first, I would see a young girl at the edge of my bed looking at a tapestry I had on the wall. I would see her every few weeks or so while living in the dorm. My roommates also claimed to have seen her but I always suspected they just wanted to participate in something exciting. The last time I saw the girl she was next to my bed and transformed into what looked like a large orb of wire with soft lights coursing through it. It’s been several years since then and I still see strange geometric or cellular beings like the one the girl transformed into every few weeks. I guess I always assumed they were ghosts or some kind of otherworldly beings. I used to keep a log of when I would see them and what they looked like. I had even tried to talk to them or jump out of bed to grab them. This article does a good job of explaining it. Nice to know I’m not just crazy (unless I fall under the Schizophrenia category).

  • I’m a 49 year old female and mine have come on fairly recent. I’m on a lot of different medications so I wondered if one or more of these is causing it……..any way, First off I typically wake up every hour on the hour. And it’s always, always the same thing that i see which looks like a very large spider, looks like a tarantula but larger like the size of a grapefruit, maybe a bit bigger. And it’s crawling up the wall and within about 10 seconds it’s gone. It’s kinda freaky but reading through just a few of these comments it seems like quite a few people see spiders. Is there any significance to seeing spiders? Well, in my case it’s only 1 spider but it’s huge.

    • I am also a 49 year old woman who has just started having these visions within the last year. And a lot of the time mine are of a giant tarantula type spider! It’s nice to hear someone else has had the same experience. On at least two occasions I have found myself jumping out of bed to get away from these spiders. I used to have wall paper on the wall behind my headboard that had black silhouettes of daisy like flowers mixed in with other geometric shapes. That wallpaper came to life nightly so I took it down and painted large stripes. Now the spiders crawl across my pillows!

  • I wake up about half the morning with geometric shapes usually going from large to small. I only get this on waking. I have it for years and never saw an explanation

  • Well my son 21 started seeing snakes in his bed room as soon as he is on the bed n trun off the light to get some sleep. It makes him paralyse by fear . As soon as he turn on the light that feeling of snakes just vanish away and he sleeps comfortably . Even if he sleeps in company in darkness he feels the same and in light he sleeps well. Few days ago he has total different feeling that as the is out some one is standing and bending on his bed ….again light is on he is comfortable ….can any body explain…..i am worried

  • I see these types of manifestations, but it can happen when I’m wide awake and not sleeping as well. It usually happens at night when I’m lying in bed. But I have not been to sleep, nor drowsy. I will see writing appearing on walls.. some times insects such as spiders will only appear if I have been sleeping and awake suddenly. The “writing” will flash before me some times it will be there as long as 60 seconds and I can make out what it says. Other times it is too distant for me to observe clearly (I am near sighted and wear glasses). I believe that some of this may actually be demonic. No one wishes to discuss that. But I believe it can be influenced by things that wish to invoke fear in people. I am still uncertain , though, if it is demonic, or its its purely physiological.

  • I usually dream of spiders.. But usually I dream that I am asleep and I wake up and there’s a spider either above me or right next to me.. I dream that I jump to get away from the spider.. the thing is when I I wake up I’m in the position I was on when I was dreaming.Whatever action I did on my dream I do while asleep… This doesn’t occur as often as it did a year ago. I used to get them at least twice a week, and now they’re rare occurrences.

  • I am 18, female. I just started having these extremely unsettling nightmares. I wake up quickly and dart my eyes around the room and usually see weird figures but if I look harder it’s not there. I just thought I’d look it up, seemed really weird to me. I’ve never had this problem before, I sleep with a small light on every night but still manage to wake up in a cold sweat terrified

  • Great article. This was the first logical explanation that I could find online. I am 46-year-old female and my began just about a year and a half ago. It was very simple I could see a black outline of a woman when I woke up. Honestly I thought it was a ghost. Nothing for about a year and then couple times a month I will wake up and be in a room that I have never seen before. The first time was quite scary as it was a dungeon. But after that if it happened again I would know that it wasn’t real and I would just look around but I was able to close my eyes and it would go away after a minute or so. I’m definitely going to try some of the ideas in the article but due to stressful conditions I may be stuck having them every once in a while. I have noticed that if I don’t sleep for 36 hours the hallucinations will happen the period of time I’m waking up.

  • I have recently had one of these hallucinations. I recently got a new table put in my bedroom that day and after falling asleep, i woke up to see a figure floating on the right side of the table. The figure looked like a young, very pale, skinny tween with straight black hair falling in her face and wearing what looked like a tattered, white night dress. After switching on the light next to my bed, she dissapeared. I then figured that i would hide myself so she couldnt find me so i pulled the duvet over my head, switched off the light and went back to sleep.

  • As I was a child often ended up sleeping next to my sister, cause I was really scared of darkness. Now (being 36) I am not afraid of that but see visions almost every night if my hubby is not there (he is pilot). It rarely happens if he is at home.
    Lately it has become only worse and makes me worried. I wake up not rested at all. I have visions from flying objects, downfalling cieling until the worst – faces and people coming closer to me. There was a period of time I saw constantly same old woman with curly gray hair sitting on my bed and looking at me..just next to me. She seemed to be nice though :D I related her to my recenlty died beloved grandmom…but that was so scary though. Now I havent seen her couple years. But other persons like a darkskined man with a huge white smile starring at me which was one of the worst experiences. This is night I saw a face of a boy ,beside all the other objects..so my night is usally- switch on the light, switch off the light…and so on. Sometimes a image can be so scary that I push with my legs or I scream..and my heartbeat is raised so much that it takes me very long to fall a sleep. As I was young I had complicated brain surgery and after that suffered on epilepsy few years, maybe it has to do smth with that. But otherwise I am fine :) I was very good in school, I am a profesional musician and speak many languages. Just to say that I dont belive my brain is damaged and earlier I was controled every year. Dont suffer on headaches or anything..I think my next step is to buy a nightlamp..I have tried to cover my eyes but I dont like it either…

  • I just posted a comment here but forgot to tell about another gruesome vision I had once. I was sleeping at a friends house, we were sleeping in the same bed. I wake up, turn around and see her body being impaled by 40-50 perfectly lined up iron rods, going vertically from down to up through her whole body. I thought she was dying and I screamed like hell of course. Today, a couple of years after it happened and a lot of analysing later, I guess what I saw must have been a bunch of geometrical lines and my brain interpreted them as being iron rods.

    I want to thank you for this article, it’s a great source of information and seems to have become a meeting place for us that experience these things. It’s a big relief to hear others talk about similar experiences and to know I’m not alone. and ps. I only now I saw that you wrote about waking up from sleep and seeing stuff, opposite of what I wrote in my comment earlier. Sorry. Thanks again.

  • I’ve had visions since I was 18. I’m always in the middle of sleep when I see things (the opposite of what the article says but in a lot of the comments i see people describing how they are like me, asleep when it happens).
    I see people, insects, sometimes a thin line sweeping through the room towards me, I’ve seen a hand come through the window curtain, a child sitting on the table in my room and in the corner of my bed next to my face. But 90 % of the time it’s insects I see, spiders and ants.
    I wake up, see these things, sometimes I scream. It lasts for 5-20 seconds and when my brain realises it can’t be real, I calm down. Sometimes I’m so scared I crawl over my partner to get away from “it” and accidentally hurt her.
    But by far the scariest thing I ever saw, or rather HEARD – was a mans voice talking to me. I was sleeping, my partner was watching TV in the other room. The hallway light outside of the bedroom was lit. I woke up and literally stood on all four in the bed, staring towards the door. I was wide awake. Something had alerted me that I was in danger I heard a mans voice talking to me as if he was right in front of me but there was no one there. The deep and dark voice said “I know where you live, you’re on the third floor. Don’t even try to imagine that you are safe there.. I’m coming up to you now.” As these words were being said, sweat started pouring down my face. I didn’t scream because I was in shock. I was waiting for the man to show up in the door opening. Nothing happended. I withdrew and started crying. It felt like my heart had imploded from fear

    I wish there was more info available but I’m happy to hear all of your stories. If someone is taking notes, here is some basic info:

Since my first vision I see things every third month to once a month, sometimes several times a week. I usually remember the experience with great detail the next day but sometimes I don’t remember at all and my partner has to tell me that I woke up screaming the other night, asking her if she can see “it”.
    I’ve started noticing a pattern, it usually happens when I’m stressed or worried in life (like if worried about work, economy or not having a stable apartment). It helps if a nearby lamp is on so that the room is not pitch black, that way I can get out of the hallucination faster.

  • This happened last month when I fell asleep sitting on the sofa. My husband had gone out. i woke and opened my eyes and saw my husband walking past the window in the front garden. AS he did not come in I thought he must be talking to the neighbour but after A few minutes I started wondering where he was. i realized to my surprise that he had not come home yet. There was nothing strange about what I had seen and did not doubt it was him. He was also surprised to hear this when he arrived half an hour later. It was not frightening but I hope it is a one off thing

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