What are Sensory Hallucinations?

Tricia Christensen
Tricia Christensen

Sensory hallucinations are visions or sounds that a person experiences that are not really there or that are distorted. In a way, they are the brain’s credible lies to the eyes or the ears. Hallucinations can also affect a person's sense of touch and may include things like feeling bugs crawling all over the body. These experiences are completely believable, and they can be very frightening for those undergoing them.

Intoxicated individuals may experience sensory hallucinations.
Intoxicated individuals may experience sensory hallucinations.

Common causes of sensory hallucinations are schizophrenia, post-traumatic stress disorder, the manic stage of bipolar disorder, and taking drugs with hallucinogenic properties, like LSD. Other prescribed medications like morphine can cause temporary hallucinations. They may also occur when a person is intoxicated or during withdrawal from alcohol. High fevers, dementia, severe head injury, or serious illnesses like end stage kidney failure may cause a person to see or hear things as well. In addition, they can be associated with the long term use of some stimulants, like cocaine.

Sensory hallucinations may be experienced during periods of high fever.
Sensory hallucinations may be experienced during periods of high fever.

Most often, these perceptions are transitory. Those experiencing them know afterward that what they saw or heard was not real. In some cases, as with dementia or schizophrenia, people have difficulty distinguishing between what is real and what is not, since the hallucinations are frequent.

Individuals suffering from PTSD may experience sensory hallucinations.
Individuals suffering from PTSD may experience sensory hallucinations.

Some hallucinations involve seeing or hearing people or voices. This is most common with schizophrenia and dementia. Most others involve seeing or hearing distortions of what is actually there. In this case, a person might look at a light bulb and see butterflies coming out of it or hear a song and be convinced it was much slower or faster than actually was the case.

Long-term use of cocaine has been linked to sensory hallucinations.
Long-term use of cocaine has been linked to sensory hallucinations.

Often, sensory hallucinations can completely reduce a person’s ability to function, when fictional perceptions are indistinguishable from what is real. Those who experience them as a result of mental illnesses have a good chance of recovery through drug treatment and therapy. Unfortunately, those with dementia may not have as good a chance. When drug users are able to stop taking drugs or end addictions, hallucinations nearly always stop, though they may get worse at first as the person goes through withdrawal.

Schizophrenia is a common cause of sensory hallucinations.
Schizophrenia is a common cause of sensory hallucinations.

Medical professionals diagnose sensory hallucinations by asking patients specific questions. Not all people will truthfully answer, however, since some think that these visions give them insight into the world. This is frequently true when the hallucinations are relatively friendly and the person experiencing them feels that he or she has a sacred duty in the world. This is also the case when the patient suffers from paranoid schizophrenia and believes that the healthcare professional is somehow going to hurt him or her.

Elderly people sometimes experience hallucinations that are caused by systemic changes in the brain.
Elderly people sometimes experience hallucinations that are caused by systemic changes in the brain.

Questions asked usually involve such things as whether a patient hears a voice, feels himself or herself being touched, or sees a person. When the patient answers honestly, the medical professional may ask him or her whether he or she has suffered a recent traumatic event or a head injury has occurred, and what prescribed or recreational drugs he or she has taken.

Medical causes other than psychiatric illness will probably be investigated to rule out severe health problems. The medical professional may perform blood tests and a physical examination. How hallucinations are treated varies significantly depending on the cause.

Some hallucinations involve hearing voices.
Some hallucinations involve hearing voices.
Tricia Christensen
Tricia Christensen

Tricia has a Literature degree from Sonoma State University and has been a frequent wiseGEEK contributor for many years. She is especially passionate about reading and writing, although her other interests include medicine, art, film, history, politics, ethics, and religion. Tricia lives in Northern California and is currently working on her first novel.

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Discussion Comments


I have hfASD (The dysfunction formerly known as Asperger's) with severe Sensory Processing Disorder (Over pressing) in all my senses including the vestibular system which is responsible for spatial orientation (Knowing where you are in physical space) that has been compounded by "Chemo Brain" and I have visual hallucinations. However I know mine are not real. They are even worse in colder weather as the denser air causes stronger Atmospheric Perspective (How the appearance of objects are altered over distance by the effects of the air between the viewer and the object) and I can actually see the air moving around objects. Easiest way for me to explain it is it is like having superman's sensory powers without having his brain which causes overloads.


I was in a head on car accident two days ago in the passenger seat of a truck. I took off my seat belt so I could grab my lighter out of my pocket when someone went to turn on the road we were driving straight on and we hit them head on but at a T-bone angle.

Anyway, my head shattered the front windshield. At the exact moment, I hit the windshield, I strongly remember seeing a blue fox. I was wondering if anyone has any insight into what this could mean.


My situation is a little different. I had a traumatic experience at a church and experienced something dropping onto the top of my head. I remember trying to wipe it off my face but couldn't. As this sensation went on, I felt the crawling sensation all over the upper portions of my body. I have had this irritating crawling sensation all over my body for 25 years.

I have made every effort to live a normal life as God would have me live. I pray that everyone going through these terrible sensations will find peace and the ability to live a normal life. Be blessed.


I just did a university pub crawl, fell over and knocked the back of my head. It's not painful and I didn't notice anything until several hours later.

Since I got home I've been unable to sleep (despite being exhausted!), I'm shaking and tachycardic as well as having hallucinations. It may be my drink was spiked by something dodgy but I can't be sure. Any suggestions about what to do?


Do people have fantasy episodes when they're high, then believe them when they're not using cocaine?


I am just starting to see/hear things that are not real/there. I have a one year old and I'm worried about child services taking him away from me. What should I do? It does not affect my ability to parent or anything.


In reference to post 12, I did various drugs for almost 10 years. I also tried to cope up with them by applying logic. But it seems the brain gets more and more confused because things get so real sometimes that they might actually be real and your brain would think of them as hallucination.

Also, if I am thinking right, then your brain might be popping out questions and evaluating everything that is right, or is it possible? Dude, this can get worse, I am telling you. My brain was first thinking about questions, then my brain was popping, and soon became real voices (perhaps schizophrenia) and then I started to obey those voices and at last my body was acting on these voices as if they were commands from my brain to my nervous system. It was very dangerous being this way. But it takes time for your brain to realize this and this would fade off in the reverse order. Believe me, it takes a lot of time and effort. God bless all.


I hear music and have done for many years. Sometimes it is orchestral and some times a chorus. I never hear actual words nor people speaking to me. It's going pretty well 24 hours a day for quite a number of years. I did get my brain scanned at one point, but nothing showed that would cause this. It's something I live with now.


I have full sensory hallucinations (episodes). Sometimes they only affect one sense, sometimes all, and sometimes just a couple of them. I was diagnosed schizophrenic, then told that was wrong.

I have been told that it is depression based, and have been told it could be bi-polar disorder. I am a 27 year old male who is a father and a husband. I have had these hallucinations for as long as I can remember. (The farthest back I can remember having an episode is second grade.) I did do drugs for a time between the ages of 11 and 17 but have been completely clean for 10 years. I take aspirin on occasion.

I work for a living and have a relatively decent IQ (157). I am a very logical person. I have trained myself to find minor details that are off or wrong, within my hallucinations so I can differentiate between them and reality. I suffer from major depression. I just want a straight answer to what is wrong with me. Anti-psychotic medication doesn't seem to work, like Abilify or seroquil. If anyone can relate or can tell me what this is, please reply.


I have sensory hallucinations when I am stressed, usually skin crawling, like ants crawling on my skin. I'm a third year occupational therapy student and Ive had these symptoms before.

Not sure if the adrenaline/stress is making my skin hypersensitive and I'm just feeling the hairs on my body more or I'm actually having a hallucination? Either way it will be gone after the exams. I have a history of OCD and anxiety, so I'm pretty prepared and know my triggers.

Hope this helps.


i think i had hallucinations because i overdosed on vyvanse. It scared me so, so, so much. everything was clay and everything was moving an changing shape and it felt like bugs were crawling all over my body. it scared me.


I'm not on drugs, but every time I go to sleep I often end up waking up and feeling as if I were touch and grabbed by demons and I'd even seen a few and heard them.

I woke up one day, face flat on my pillow and I couldn't breathe and I swear I heard satan's voice on some real paranormal stuff. I still to this day feel ashamed to say that I am afraid to go to sleep and probably haven't slept for six hours in a day in a while. I know I this may seem crazy but I think I might be losing my mind.


i had auditory hallucinations when i was an alcoholic. it would be during my sleep and then my body would get paralyzed, but my mind conscious or sub-conscious resulting in sleep paralysis.

Then i have heard varying sounds and voices like a baby crying, songs, gun shot, my mother's voice. For ex. I could swear I heard a song, but then when I wake up there is no song. Was really scary but since I stopped drinking 1.5 years ago, I stopped having sleep paralysis and hallucinations.


My friend just started to have hallucinations and has not slept in a week. He chases people in the attic and sees people that are not there. It was all of a sudden too. He is being evaluated and has to be strapped down for four hours at a time and he has not ate anything in a week. what caused this and what will make it better.


I have been on Nortriptyline for Migraines as well. I have post-injury head trauma. From the start of taking it I have seen a spider looking thing every morning when I wake up. It freeks me out. I am on 50mg as of now and my doctor wants me to work up to 100mg. Anon8697 how many mg are you on? And in the five years has it helped you? now that you're off of it how do you feel?


My three year old son recently started to feel bugs in his ear and often feels ants on his face. He constantly will wipe his ear, nose or mouth and extend his arm out as if he is brushing them off. I'm not sure what this can be and I am taking him to his pediatrician on Monday. Does anyone have any information that can help?


My mother went on Nortriptyline and began having extremely vivid hallucinations.


i read that nortriptyline can cause hallucinations, especially when you've overdosed on the medication. be sure to tell your doctor about the side effect, i think it's a pretty rare one.


Has anyone ever had hallucinations (seeing and feeling things) while on the drug Nortriptyline? It's an antidepressant but is also used to treat migraines. I've been on this drug for 5 years for migraines and suddenly started having hallucinations. Seeing things when I woke up and feeling things crawling around in my bed when I was trying to sleep. I stopped the drug about 3 weeks ago. Things have gotten better but are still not completely gone. Does it take a long time? Does anyone have any information that can help me?

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