Sensory hallucinations are seeing or hearing things that are not there, or seeing or hearing distorted images or sounds. In a way, sensory hallucinations are the brain’s credible lies to the eyes or the ears. Sensory hallucinations can also affect one’s sense of touch, and may include feelings like bugs are crawling all over one’s body. Hallucinations are believable, and can be very frightening for those undergoing them.

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 sensory hallucinations. Sensory hallucinations may also occur when one is intoxicated or during withdrawal from alcoholism. High fevers, dementia, severe head injury, or serious illnesses like end stage kidney failure may cause such hallucinations. Also, long term use of some stimulants like cocaine and crack are indicated in sensory hallucinations.

Most often, sensory hallucinations are transitory. Those experiencing them know afterwards 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 since sensory hallucinations are frequent.

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

Often sensory hallucinations can completely reduce a person’s ability to function, when fictional perceptions are indistinguishable from what is real. Those with mental illness, have a great chance of recovery through drug treatment and therapy. Sadly those with dementia may not have as good a chance. When drug users are able to stop taking drugs or end addictions sensory hallucinations nearly always stop, though they may at first worsen during detoxification.

Doctors diagnose sensory hallucinations by asking specific questions of those experiencing such hallucinations. Not all people will truthfully answer, however, since some think these visions give them insight into the world. This is frequently true when hallucinations are relatively friendly and the person experiencing them feels they have a sacred duty in the world. This is also the case when visions or auditory perceptions have affected the paranoid schizophrenic, who may believe the doctor is somehow going to hurt him or her.

Questions asked usually involve such things as whether a patient hears a voice, feels himself being touched, or sees a person. When truthful answers can be obtained, physicians may further ask whether a recent traumatic event has occurred, a recent head injury has occurred, and what prescribed or recreational drugs the patient may use.

Medical causes other than psychiatric illness will probably be investigated to rule out severe health problems. These may include blood tests, and physical examination, with follow up specific examination of any possible diseased areas of the body. Treatment varies significantly and depends on cause.