Definition
A hallucination is a psychic phenomenon in which the subject perceives as real what in reality is only imaginary (perception without an object).
Hallucinations are typically found in the presence of mental alterations caused by neurological and psychiatric diseases (such as degenerative dementias, schizophrenia and delirium tremens in case of chronic alcoholism).
In other cases, they depend on the use of drugs, such as: psilocybin (alkaloid in Basomiceti mushrooms), mescaline (peyote alkaloid, small Mexican cactus), lysergic acid and relative diethylamide (LDS).
The main forms of hallucinations are distinguished according to the organ of sense concerned. The symptoms and the accompanying signs concur in determining the origin of these manifestations.
- The auditory (or auditory) hallucinations are the most frequent and appear as mental disorders with chronic course (in particular, in schizophrenia). Often, they are perceived as phrases or speeches with threatening, imperative or disparaging content.
- Visual hallucinations consist of the perception of non-existent people or images; they usually appear in acute organic diseases of the brain, but can also occur in alcohol or drug intoxication, in schizophrenia, in diseases with fever (febrile delirium) and in encephalopathy.
- Olfactory hallucinations are characterized by the perception of non-existent odors emanating from the body of the subject himself or of another person. They appear in the temporal lobe lesions of the brain and in schizophrenia.
- Tactile hallucinations are perceptions of non-existent tactile stimuli, generally described as insects that crawl above and below the skin; occur in alcohol withdrawal syndrome and cocaine abuse.
- The cenesthetic hallucinations are sensations of alteration of the consistency and of the function of the viscera or of invasion by foreign bodies or animals.
Hallucinations can occur, in particular circumstances, even in healthy people (eg deprivation from sleep or situations of intense stress).
Possible Causes * of Hallucinations
- Alcoholism
- Vascular dementia
- Major depression
- Postpartum depression
- Bipolar disorder
- Post-Traumatic Stress Disorder
- Encephalitis
- Hypochondria
- Creutzfeldt-Jakob disease
- Alzheimer's disease
- Parkinson's disease
- Porphyria
- Korsakoff psychosis
- Anger
- Salmonella
- Schizophrenia
- Serotonin syndrome
