Definition
Hallucinations are perceptions that do not occur in response to a corresponding sensory stimulus. This means that the affected person hears, sees, tastes, smells or feels something without an external stimulus. A qualified statement about existing hallucinations can only be made if a healthy fellow human being is in the same situation but feels nothing of the kind.
Functional hallucinations are a special form of hallucination in which patients only perceive the hallucinations during an actual sensory stimulus. For example, voices are heard parallel to the chirping of birds. How the affected person assesses the situation can vary from person to person. The evaluation of the hallucinations ranges from absolute credibility – the affected person thinks that it is a real stimulus – to a dubious attitude, to the insight that it is a hallucination and not an existing sensory stimulus.
Causes
The causes of hallucinations can be very diverse. There does not necessarily have to be a pathological process behind this psychiatric phenomenon. Various substances can also trigger hallucinations.
Legal and illegal drugs play a very important role. Alcohol is the most widely consumed drug in Germany. Therefore, most patients with addiction problems are alcoholics.
Various health-critical conditions can arise during withdrawal. Alcohol and cannabis, as well as hallucinogenic (hallucinogenic) substances such as LSD can cause various types of hallucinations, which are, however, in contrast to the majority of disease-related phenomena, only short-lived. The typical illnesses, which can include hallucinations as a symptom, come from the fields of psychiatry and neurology.
People suffering from schizophrenia in particular often experience hallucinations on various sensory levels during the course of their illness. Important other diseases are epilepsy, organic psychoses, depression, various lesions in the brain and tumors of certain brain areas. Hallucinations can trigger psychologically critical situations in the affected person and induce him/her to perform actions with serious consequences.
Since there is a possibility that the hallucinator dies, all causes must be carefully investigated. The consumption of marijuana, colloquially also called grass or weed, can in rare cases lead to hallucinations. They occur either in connection with the use or as a symptom of schizophrenia or paranoid hallucinatory psychosis as a result of long-term drug abuse.
Such a psychosis is a mental illness as a result of drug use. Scientific studies have shown that, especially during puberty, marijuana use can lead to psychosis even in people who are not otherwise burdened by other risk factors. Hallucinations often affect users who are using marijuana for the first time at all or for the first time in large quantities.
An overdose in the sense that it is dangerously possible with other drugs does not occur with grass, but the undesirable side effects can make the user nervous, even anxious or panicky. Hallucinations that occur have a negative influence on these side effects, such as palpitations or shortness of breath, and may worsen the condition of the user. Speed is the scene name of amphetamine, which belongs to the group of stimulant drugs.
Cocaine, crystal meth and ecstasy are also representatives of this group of stimulants. The use of speed in small doses initially has a stimulating effect. The user feels awake, concentrated and extremely powerful.
However, if the dose rises above a certain level, for example by taking too much from the outset or after a short time, amphetamines can also lead to hallucinations. In some cases, twice the amount of speed that one would normally consume is sufficient as a threshold dose. After several days of speed consumption a so-called amphetamine psychosis can occur.
This drug-induced psychosis is characterized, among other things, by its strong hallucinatory symptoms, which are accompanied by states of confusion, paranoid and anxious thoughts and phases of severe exhaustion. The hallucinations are comprehensive. Those affected hear voices and see things that other people cannot see – optical and acoustic hallucinations occur.
Sometimes tactile hallucinations (feeling something that is not real) are also reported.The affected person feels a stinging or tingling sensation on the skin, which, in combination with the delusional thoughts, can be interpreted as the exposure of insects on the skin, for example. Alcohol can also cause hallucinations. However, such symptoms are always associated with chronic, i.e. long-term alcohol abuse.
There are two possible scenarios: the hallucinations occur during a withdrawal phase, when the patient has stopped drinking, or the disorders occur during intoxication. Cold alcohol withdrawal can lead to an alcohol withdrawal syndrome (predelirium) or worse, to an alcohol delirium. Both conditions are potentially dangerous and are accompanied by various physical and psychiatric symptoms.
The predelirium usually lasts from 3 days to a week and can trigger hallucinations, in addition to seizures, depressive and anxious moods, concentration problems and insomnia. The excited state of the patient makes him more susceptible to visual or acoustic overstimulation. However, the hallucinations are very ephemeral and only ever occur briefly, especially on the visual level.
In the case of an alcohol delirium, the situation becomes more dangerous. Up to a quarter of all affected patients die at the onset of an alcohol delirium if no medical help is sought. The symptoms of the predilection are intensified in the case of a fulminant delirium and are accompanied by severe orientation and consciousness disorders.
Hallucinations also become more intense. For example, animals or objects are perceived visually over a longer period of time. The patient is not aware that this is a hallucination – he fantasizes a lot into his environment.
In contrast to the withdrawal diseases described above, alcohol hallucinosis is a pathological condition that occurs during alcohol intoxication. In contrast to a hallucination, one speaks of a hallucinosis when characteristically only one sensory perception is affected by the false sensation – in this case acoustic perception, hearing. For example, patients hear voices but know that it is a hallucination.
This circumstance, known as pseudo-hallucination, is a characteristic of alcohol hallucinosis, along with a clear consciousness and an anxious basic mood. Through therapy with neuroleptics (antipsychotic drugs) and controlled alcohol withdrawal, alcohol hallucinosis can usually be cured. Young or old people in particular may develop hallucinations during an episode of high fever or have severe nightmares while sleeping.
These conditions, known as “fever fantasies” or “fever delirium”, are a reaction of the brain to the elevated temperature. When body temperature rises due to fever, metabolic activity and excitability of brain cells also increase. Irritations can be triggered more easily and in some cases lead to corresponding false sensations.
Usually feverish children have bad dreams and contact their parents at night. Due to the high activity of the brain, the dreams are experienced as very intense and real, which frightens the children. Even a short time after awakening, the dream state can be maintained.
The children then appear awake, but are actually not yet fully conscious and continue to experience their dream. These intensive dream phases can also occur during the day when the fever is high. Such daydreams must again be distinguished from hallucinations, which are perceived as still more real, but can also be observed when the fever is high.
Such fever fantasies may be frightening for the child and the parents, but are usually harmless. However, if such a condition degenerates into a febrile convulsion, a doctor must be consulted immediately. Febrile convulsions are a reaction of the brain to the extreme excitability and are probably associated with a genetic predisposition.