What are Hallucinations?

Hallucinations are false perceptions that occur without an external stimulus, unlike illusions which are a mistaken perception of real things that are caused by an external stimulus. Hallucinations may be caused by a wide variety of things and occur within all senses of the body. However, a person must be awake to experience them, unlike dreams which occur while someone is sleeping.

People who suffer from mood disorders such as schizophrenia and depression frequently hallucinate. Schizophrenics commonly hear voices and sounds which are auditory hallucinations that are believed to be caused by high levels of dopamine in a person’s brain. Although schizophrenics also experience visual hallucinations, seeing things which aren’t really there, they are most common in manic depressives, especially elderly people.

Another common cause is drug use. Regardless of the legality of the drug in question, hallucinogens cause false perceptions because they disrupt the normal balance of neurotransmitters in a person’s brain. People who use cocaine, crystal meth or other amphetamines may hallucinate because of an overproduction of dopamine in the brain. Lysergic acid diethylamide, or LSD, is responsible for blocking the functions of the neurotransmitters serotonin and norepinephrine. Phencyclidine (PCP) causes people to hallucinate by blocking glutamate. Haptic hallucinations, which occur when a person feels something which is not there, are rare in general, but are seen mostly in drug users.

Medications prescribed for depression, sleep aids and certain anesthetics may cause someone to hallucinate. Medications including ketamine, paroxetine, mirtazapine and zolpidem have hallucinogenic side effects. Antiretroviral medications used to treat HIV and antipsychotics used for Alzheimer’s patients are also believed to cause hallucinations in some people.

In addition to drug use, alcohol use may also cause people to hallucinate. More specifically, the abrupt cessation of alcohol use may cause auditory hallucinations in people. After a few days of withdrawal, when the delirium tremens (DTs) begin, it is common for people to visually hallucinate.

Disorders caused by the imbalance of neurotransmitters in the brain commonly cause people to hallucinate. One example is narcolepsy, where people uncontrollably sleep for brief periods. In addition to auditory and visual hallucinating, it is common for narcoleptics to experience gustatory and olfactory hallucinations. A gustatory hallucination occurs when a person tastes something that is not present, while an olfactory hallucination occurs when a person smells something that is not there.

You might also Like


Discuss this Article

Post 4


There is a genuine vision which people may have for the future, and there is such thing as genuine motivation and ambition based on a sense of destiny. Not all senses of purpose are delusional. The main difference between a false hallucination and a real desire or purpose is the fact that the latter case has a solid foundation in reality and wants to help others, rather than merely exalt the self.

Post 3

Psychotic hallucinations may include delusions of grandeur and a sense of manifest destiny. Many people believe that they have been chosen by God for a special mission when they have these kinds of hallucinations. The resulting actions and conviction of profound purpose may be disturbing, and they may lead others to do ridiculous things along with them.

Post 2

Gustatory and olfactory hallucinations are not pleasant, but are possibly the safest form of hallucinations. When someone tastes and smells things that are not there, it is important for them to seek help. Seeing and hearing things can be much worse, however.

Post 1

Dementia can cause a number of hallucinations to occur, especially in elderly people who have had brain problems or deterioration. Many of these hallucinations may relate to distant memories of younger years. Much of recent history can also be forgotten, and someone suffering from dementia might call close friends by the names of old friends who have passed away.

Post your comments

Post Anonymously


forgot password?