What causes hallucinations?
There are numerous medical and psychiatric causes of hallucinations. Some of the common causes include the following:
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.