Hallucinations


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Hallucinations

 

Definition

Hallucinations are false or distorted sensory experiences that appear to be real perceptions. These sensory impressions are generated by the mind rather than by any external stimuli, and may be seen, heard, felt, and even smelled or tasted.

Description

A hallucination occurs when environmental, emotional, or physical factors such as stress, medication, extreme fatigue, or mental illness cause the mechanism within the brain that helps to distinguish conscious perceptions from internal, memory-based perceptions to misfire. As a result, hallucinations occur during periods of consciousness. They can appear in the form of visions, voices or sounds, tactile feelings (known as haptic hallucinations), smells, or tastes.
Patients suffering from dementia and psychotic disorders such as schizophrenia frequently experience hallucinations. Hallucinations can also occur in patients who are not mentally ill as a result of stress overload or exhaustion, or may be intentionally induced through the use of drugs, meditation, or sensory deprivation. A 1996 report, published in the British Journal of Psychiatry, noted that 37% of 4,972 people surveyed experienced hypnagogic hallucinations (hallucinations that occur as a person is falling to sleep). Hypnopomic hallucinations (hallucinations that occur just upon waking) were reported by 12% of the sample.

Causes and symptoms

Common causes of hallucinations include:
  • Drugs. Hallucinogenics such as ecstasy (3,4-methylenedioxymethamphetamine, or MDMA), LSD (lysergic acid diethylamide, or acid), mescaline (3,4,5-trimethoxyphenethylamine, or peyote), and psilocybin (4-phosphoryloxy-N, N-dimethyltryptamine, or mushrooms) trigger hallucinations. Other drugs such as marijuana and PCP have hallucinatory effects. Certain prescription medications may also cause hallucinations. In addition, drug withdrawal may induce tactile and visual hallucinations; as in an alcoholic suffering from delirium tremens (DTs).
  • Stress. Prolonged or extreme stress can impede thought processes and trigger hallucinations.
  • Sleep deprivation and/or exhaustion. Physical and emotional exhaustion can induce hallucinations by blurring the line between sleep and wakefulness.
  • Meditation and/or sensory deprivation. When the brain lacks external stimulation to form perceptions, it may compensate by referencing the memory and form hallucinatory perceptions. This condition is commonly found in blind and deaf individuals.
  • Electrical or neurochemical activity in the brain. A hallucinatory sensation—usually involving touch—called an aura, often appears before, and gives warning of, a migraine. Also, auras involving smell and touch (tactile) are known to warn of the onset of an epileptic attack.
  • Mental illness. Up to 75% of schizophrenic patients admitted for treatment report hallucinations.
  • Brain damage or disease. Lesions or injuries to the brain may alter brain function and produce hallucinations.

Diagnosis

Aside from hypnogogic and hypnopompic hallucinations, more than one event suggests a person should seek evaluation. A general physician, psychologist, or psychiatrist will try to rule out possible organic, environmental, or psychological causes through a detailed medical examination and social history. If a psychological cause such as schizophrenia is suspected, a psychologist will typically conduct an interview with the patient and his family and administer one of several clinical inventories, or tests, to evaluate the mental status of the patient.
Occasionally, people who are in good mental health will experience a hallucination. If hallucinations are infrequent and transitory, and can be accounted for by short-term environmental factors such as sleep deprivation or meditation, no treatment may be necessary. However, if hallucinations are hampering an individual's ability to function, a general physician, psychologist, or psychiatrist should be consulted to pinpoint their source and recommend a treatment plan.

Treatment

Hallucinations that are symptomatic of a mental illness such as schizophrenia should be treated by a psychologist or psychiatrist. Antipsychotic medication such as thioridazine (Mellaril), haloperidol (Haldol), chlorpromazine (Thorazine), clozapine (Clozaril), or risperidone (Risperdal) may be prescribed.

Prognosis

In many cases, chronic hallucinations caused by schizophrenia or some other mental illness can be controlled by medication. If hallucinations persist, psychosocial therapy can be helpful in teaching the patient the coping skills to deal with them. Hallucinations due to sleep deprivation or extreme stress generally stop after the cause is removed.

Resources

Organizations

American Psychological Association (APA). 750 First St. NE, Washington, DC 20002-4242. (202) 336-5700. ttp://www.apa.org.
National Alliance for the Mentally Ill (NAMI). Colonial Place Three, 2107 Wilson Blvd., Ste. 300, Arlington, VA 22201-3042. (800) 950-6264. http://www.nami.org.

Key terms

Aura — A subjective sensation or motor phenomenon that precedes and indicates the onset of a neurological episode, such as a migraine or an epileptic seizure.
Hypnogogic hallucination — A hallucination, such as the sensation of falling, that occurs at the onset of sleep.
Hypnopompic hallucination — A hallucination that occurs as a person is waking from sleep.
Sensory deprivation — A situation where an individual finds himself in an environment without sensory cues. Also, (used here) the act of shutting one's senses off to outside sensory stimuli to achieve hallucinatory experiences and/or to observe the psychological results.

Patient discussion about Hallucinations

Q. Give life to her please! Here is a really confusing question to you all. But your reply is a life for her. I know someone who is bipolar and she thinks that her ‘brother’ sexually molested her when they were kids. Can this be a delusion? Or hallucinating?

A. Im going to answer this question a little different;What if she is telling the truth,and her brother is planning on no body believing her? because she has this disease?---keep that in mind when you take her to the DR--mrfoot56

More discussions about Hallucinations
References in classic literature ?
Either I was being dogged, watched, followed, day and night, indoors and out, or I was the victim of a very ominous hallucination.
He plodded on for half an hour, when the hallucination arose again.
And in all cases where images, originally recognized as such, gradually pass into hallucinations, there must be just that "force or liveliness" which is supposed to be always absent from images.
Of course, I need not tell you that this was what you will call an hallucination and I call an apparition.
Well, perhaps it was a hallucination, I don't know," said Parfen.
It was very terrible if true; if a temporary hallucination, sad.
Researchers from Orygen, the National Centre of Excellence for Youth Mental Health; the University of Melbourne; Port Phillip Prison and University Hospital of Gran Canaria Dr Negrin, Spain, have shown that childhood sexual, physical and emotional abuse are associated with severe hallucinations in schizophrenia and other psychotic disorders.
THE difference between psychedelic mushrooms and regular mushrooms is that the former contains a brain-altering compound that can cause hallucinations.
However, more than half of people living with Parkinson's also experience a lesser known aspect of the disease -- hallucinations and delusions.
According to Wikipedia, hallucinations involve sensing things such as visions, sounds, or smells that seem real but are not.
BERLIN--Teens who reported psychotic symptoms--especially hallucinations --on a baseline mental health screening were twice as likely to develop persistent psychiatric symptoms over the next year as were those without such experiences.
When they occur as the sleeper is waking up, the hallucinations are commonly "the sensation of falling and the feeling of a presence in the room.