Hallucinations are sensory experiences that appear real but are created by your mind. They can affect all five of your senses. For example, you might hear a voice that no one else in the room can hear or see an image that isn’t real.
These symptoms may be caused by mental illnesses, the side effects of medications, or physical illnesses like epilepsy or alcohol use disorder.
You may need to visit a psychiatrist, a neurologist, or a general practitioner depending on the cause of your hallucinations.
Treatment may include taking medication to treat a health condition. Your doctor may also recommend adopting different behaviors like drinking less alcohol and getting more sleep to improve your hallucinations.
Types of hallucinations
Hallucinations may affect your vision, sense of smell, taste, hearing, or bodily sensations.
1. Visual hallucinations
Visual hallucinations involve seeing things that aren’t there. The hallucinations may be of objects, visual patterns, people, or lights.
For example, you might see a person who’s not in the room or flashing lights that no one else can see.
2. Olfactory hallucinations
Olfactory hallucinations involve your sense of smell. You might smell an unpleasant odor when waking up in the middle of the night or feel that your body smells bad when it doesn’t.
This type of hallucination can also include scents you find enjoyable, like the smell of flowers.
3. Gustatory hallucinations
Gustatory hallucinations are similar to olfactory hallucinations, but they involve your sense of taste instead of smell.
These tastes are often strange or unpleasant. Gustatory hallucinations (often with a metallic taste) are a relatively common symptom for people with epilepsy.
4. Auditory hallucinations
Auditory hallucinations are among the most common type of hallucination. You might hear someone speaking to you or telling you to do certain things. The voice may be angry, neutral, or warm.
Other examples of this type of hallucination include hearing sounds, like someone walking in the attic or repeated clicking or tapping noises.
5. Tactile hallucinations
Tactile hallucinations involve the feeling of touch or movement in your body. For example, you might feel that bugs are crawling on your skin or that your internal organs are moving around. You might also feel the imagined touch of someone’s hands on your body.
What causes hallucinations?
• Mental health conditions
Mental illnesses are among the most common causes of hallucinations. Schizophrenia, dementia, and delirium are a few examples.
• Substance use
Substance use is another fairly common cause of hallucinations. Some people see or hear things that aren’t there after drinking too much alcohol or taking drugs like cocaine.
Hallucinogenic drugs like LSD and PCP can also cause you to hallucinate.
• Lack of sleep
Not getting enough sleep can also lead to hallucinations. You may be more prone to hallucinations if you haven’t slept in multiple days or don’t get enough sleep over long periods of time.
It’s also possible to experience hallucinations right before falling asleep, known as hypnagogic hallucinations, or right before waking up from sleep, known as hypnopompic hallucinations.
Certain medications taken for mental and physical health conditions can also cause hallucinations. Parkinson’s disease, depression, psychosis, and epilepsy medications may sometimes trigger hallucination symptoms.
Other conditions can also cause hallucinations. These can include:
• high fevers, especially in children and the elderly
• social isolation, particularly in older adults
• deafness, blindness, or vision problems
• epilepsy (in some cases, epileptic seizures can cause you to see flashing shapes or bright spots)
• terminal illnesses, such as stage 3 HIV (AIDS), brain cancer, or kidney and liver failure
Common Causes of Hallucinations
Hallucinations most often result from:
• Schizophrenia. More than 70% of people with this illness get visual hallucinations, and 60%-90% hear voices. But some may also smell and taste things that aren’t there.
• Parkinson’s disease. Up to half of people who have this condition sometimes see things that aren’t there.
• Alzheimer’s disease. and other forms of dementia, especially Lewy body dementia. They cause changes in the brain that can bring on hallucinations. It may be more likely to happen when your disease is advanced.
• Migraines. About a third of people with this kind of headache also have an “aura,” a type of visual hallucination. It can look like a multicolored crescent of light.
• Brain tumor. Depending on where it is, it can cause different types of hallucinations. If it’s in an area that has to do with vision, you may see things that aren’t real. You might also see spots or shapes of light. Tumors in some parts of the brain can cause hallucinations of smell and taste.
• Charles Bonnet syndrome. This condition causes people with vision problems like macular degeneration, glaucoma, or cataracts to see things. At first, you may not realize it’s a hallucination, but eventually, you figure out that what you’re seeing isn’t real.
• Epilepsy. The seizures that go along with this disorder can make you more likely to have hallucinations. The type you get depends on which part of your brain the seizure affects.
www.healthline.com ( Everything You Need to Know About Hallucinations). Written by Chitra Badii — Updated on July 10, 2019
www.webmd.com ( Hallucinations)