Hallucinations

and Sabine Schrör, medical journalist

Martina Feichter studied biology with an elective subject pharmacy in Innsbruck and also immersed herself in the world of medicinal plants. From there it was not far to other medical topics that still captivate her to this day. She trained as a journalist at the Axel Springer Academy in Hamburg and has been working for since 2007 - first as an editor and since 2012 as a freelance writer.

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Sabine Schrör is a freelance writer for the medical team. She studied business administration and public relations in Cologne. As a freelance editor, she has been at home in a wide variety of industries for more than 15 years. Health is one of her favorite subjects.

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Hallucinations are hallucinations: they see, hear, feel or smell something that does not exist. However, you yourself are convinced that your sensory perception is real. Hallucinations can be signs of psychosis, but can also occur when you are half asleep, under the influence of hypnosis or drugs, and when you have a fever. Read here about the forms in which hallucinations can occur, the causes behind them and how they can be treated.

Brief overview

What are hallucinations? Illusions of the senses that are experienced as real. All senses can be affected - hearing, smelling, tasting, seeing, touching. Differences in intensity and duration are possible.
Causes: e.g.Lack of sleep, exhaustion, social isolation, migraines, tinnitus, eye diseases, high fever, dehydration, hypothermia, stroke, traumatic brain injury, epilepsy, dementia, schizophrenia, depression, alcohol or other drugs, poisoning, medication.
When to the doctor Always immediately, except for hallucinations due to lack of sleep.
What does the doctor? Preliminary discussion (anamnesis), physical examination, if necessary blood tests and other measures such as ENT or eye examination, neurological examination, electroencephalography (EEG), computed tomography (CT), magnetic resonance imaging (MRT), psychological tests.

Hallucinations: description

See, hear, smell, taste, feel - hallucinations can affect all senses. It is characteristic of the delusions that those affected consider them to be real. Important types of hallucinations are:

Acoustic hallucinations: those affected hear imaginary sounds, for example hissing, cracking or music.
Teleological hallucinations: a special form of acoustic hallucinations in which those affected hear imaginary voices that, for example, issue commands or warn of an alleged danger.
Optical hallucinations: Those affected see flashes of light or sparks, for example, but also people, animals or objects that are not real.
Smell hallucinations (olfactory hallucinations): Those affected perceive a - mostly unpleasant - scent, for example the smell of gas or petrol, putrefaction or putrefaction.
Taste hallucinations (gustatory hallucinations): These hallucinations often appear together with olfactory hallucinations. Most of the time, those affected register an unpleasant (e.g. salty, soap-like, sulphurous or faecal) odor.
Touch and touch hallucinations (tactile or haptic hallucinations): These are imagined touches. Those affected believe, for example, that they are being touched, strangled or held. Some feel hot water running over their arm or ants crawling over their bodies.
Body hallucinations (coenesthesia): With these hallucinations, the body's perception is disturbed. Typical is, for example, the belief that internal organs have been changed or that the two halves of the brain are rubbing against each other. The transition between body and tactile hallucinations is fluid.
Body hallucinations: Those affected have the feeling that their body is being manipulated from outside (e.g. irradiated or electrified).
Kinesthetic hallucinations are delusions of the sense of movement. For example, those affected believe that their body or part of it is being moved from outside.
Vestibular hallucinations: people feel like they are floating or falling.
Hypnagogic and hypnopompe hallucinations: These mostly optical or acoustic hallucinations occur when half asleep when falling asleep (hypnagogic) or when waking up (hypnopompe).

Hallucinations can vary in intensity. The spectrum of acoustic hallucinations ranges from soft, indistinct murmuring to loud, garish screaming. Optical illusions can appear as shadowy phenomena or in the form of people and things that are perceived in great detail.

Hallucinations usually start suddenly. It lasts for a few hours, days or weeks, but can also become chronic and lead to delirium. In this state, those affected can no longer record, process and save information in a structured manner. As a result, they can no longer orientate themselves and remember correctly, and often hallucinate even more. In addition, there is fear, sometimes excitement, as well as an acute danger to oneself or others.

Differentiation from hallucinosis

Experts speak of hallucinosis in the case of recurring hallucinations. However, the awareness of those affected is not impaired. One example is alcoholic hallucinosis - a psychosis with persecution delusions and strong hallucinations, especially dermatozoal delusions, that occurs in long-term, chronic alcoholism. This means the feeling of small insects, worms, parasites or other vermin crawling on and under the skin.

Differentiation from pseudo-hallucinations

Pseudo-hallucinations are to be distinguished from real hallucinations: In the latter, those affected know that their perception is not real. On the other hand, those affected interpret real hallucinations as actually existing sensory impressions.

Differentiation from delusions

While hallucinations are false senses, delusions are false thoughts and beliefs such as paranoia. Those affected cannot simply give up, even if fellow human beings provide them with “counter-evidence”.

Hallucinations: causes

Hallucinations can be triggered by psychoses or other diseases of the central nervous system. Chemical substances such as medication and drugs can also cause hallucinations. Sometimes, however, hallucinations also have a completely harmless explanation. In some cases, for example, chronic lack of sleep is the trigger.

The main causes of hallucinations are:

Pronounced lack of sleep or complete exhaustion.
Social isolation, for example in solitary confinement or a long stay in a low-stimulus environment (e.g. in a dark, quiet room): Hallucinations are a natural reaction of the body to a lack of external stimuli. Illusions of the senses in meditative exercises (spiritual ecstasy and visions) are considered special forms.
Migraine: Some migraine patients suffer from optical hallucinations such as flashes of light, spots or patterns before the actual headache phase. One then speaks of a migraine with aura.
Tinnitus (noises in the ear): If the ear rings or rustles without an external sound source, tinnitus is present.
Eye diseases such as retinal detachment, damage to the optic nerve or the visual center can also cause optical hallucinations, for example flashes of light, spots, patterns, spots of light or color.
High fever: Hallucinations with excitement, restlessness, lack of orientation, etc. can occur with a high fever.
Dehydration (desiccosis): If there is a very strong lack of fluids, it can lead to states of excitement, hallucinations and cramps.
Hypothermia: Hallucinations are possible even with severe hypothermia.
Stroke: A stroke can cause hallucinations, delusions, confusion, and impaired memory and consciousness.
Inflammation of the brain (encephalitis): They are usually caused by a viral infection (such as measles, mumps, herpes simplex or TBE). In addition to indifference, drowsiness and confusion, possible symptoms also include agitation, behavioral problems and hallucinations.
Traumatic brain injury: Hallucinations and delusions sometimes occur as part of a traumatic brain injury.
Epilepsy: In some cases, epileptic seizures are accompanied by hallucinations, such as hallucinations of smell and taste.
Dementia: Dementia diseases such as Alzheimer's and vascular dementia can be associated with hallucinations and delusions. Those affected also become increasingly forgetful and confused; anxiety and excitement as well as personality changes occur.
Huntington's Disease (Chorea): Huntington's Disease is an inherited, progressive brain disease that causes movement disorders and mental changes. Hallucinations and delusions are also possible.
Schizophrenia: This is where bizarre delusions and hallucinations often occur, such as acoustic hallucinations in which those affected hear voices giving them orders. Taste and smell hallucinations, bizarre or erotic body hallucinations are also possible.
Depression: Excruciating hallucinations and / or delusions with depression and lack of drive can be signs of depression.
Alcohol abuse: Hallucinations (especially acoustic hallucinations) and delusions can occur in alcohol intoxication. Alcohol addicts can also develop hallucinations during withdrawal.
Substance abuse: Illicit drugs can also cause hallucinations and delusions. This is especially true for hallucinogens (such as LSD, “magic mushrooms”, mescaline). Soothing (like cannabis) and stimulating drugs (like amphetamines, ecstasy) can also have high doses of hallucinogenic effects. Drug addicts can also develop hallucinations during withdrawal.
Poisoning: Hallucinations and delusions, combined with noticeably dilated pupils, indicate poisoning, for example with deadly nightshade or thorn apple. Parts of these plants are sometimes used as hallucinogenic drugs or accidentally eaten by children.
Side effect of medication: Various drugs can cause hallucinations and delusions as a side effect. This applies, for example, to drugs for epilepsy (anti-epileptic drugs), Parkinson's and allergies (antihistamines) and drugs for malaria prophylaxis.

Hallucinations: when do you need to see a doctor?

Illusions of the senses that occur when there is a pronounced lack of sleep, for example, generally do not require medical attention. Otherwise, you should always consult a doctor in the event of a hallucination to clarify the possible cause. This is especially true in the following cases:

Hallucinations and delusions when taking medication: Talk to the doctor treating you immediately.
Hallucinations and delusions from alcohol or drug abuse: If possible, see a psychiatrist on the same day.
Hallucinations and delusions with noticeably wide pupils: Suspected poisoning (e.g. with thorn apple or deadly nightshade)! Call the emergency doctor immediately and do not leave the person alone!
Frequently occurring, bizarre delusions and hallucinations (such as commenting voices, strange body feelings, bizarre behavior): Signs of schizophrenia. Call the ambulance and don't leave them alone. Make sure he stays in place until the ambulance arrives.
Hallucinations (like small animals on the skin) and delusions with anxious restlessness or excitement, confusion, memory disorders and possibly impaired consciousness, sweating and tremors: Suspicion of acute organic psychosis and delirium with alcohol withdrawal, high fever, hypothermia, stroke, encephalitis etc. Call the ambulance and don't leave them alone.
Tormenting hallucinations and / or delusions with depression and lack of drive: Suspected depression. Call the emergency doctor and do not leave the person alone until they arrive.

Hallucinations: what does the doctor do?

The doctor will first ask the patient in detail about the medical history (anamnesis). For example, it is important when and how often the hallucinations occur and what type they are. This information will help the doctor determine the cause of the hallucinations, possibly along with various tests:

The physical exam is part of the routine when someone comes to the doctor with unclear symptoms such as hallucinations.

The analysis of blood samples is also carried out very often, especially if there is suspicion of alcohol and drug abuse, as well as possible poisoning.

ENT examinations are important when someone hears non-existent sounds (suspected tinnitus).

An ophthalmological examination is due if certain eye diseases or damage to the optic nerve or visual center could be responsible for optical hallucinations.

The neurological examination of the nerve tracts can be informative if, for example, migraines, strokes, epilepsy or encephalitis are possible causes of hallucinations.

Electroencephalography (EEG) is used to measure electrical brain waves if the doctor suspects that the hallucinations are caused by epilepsy or encephalitis, for example.

Computed tomography (CT) and magnetic resonance imaging (MRI) can help if you suspect a stroke, encephalitis, traumatic brain injury, or dementia.

An examination of the cerebrospinal cord fluid (liquor diagnostics), which is taken from the spinal cord (liquor puncture), serves to detect or rule out encephalitis.

If there are concrete suspicions, further, specific examinations are scheduled, such as a genetic test if Huntington's disease is suspected or special questionnaires if schizophrenia could trigger the hallucinations.

Hallucinations: You Can Do It Yourself

Hallucinations are generally a case for the doctor and require treatment for the underlying condition. However, if a pronounced lack of sleep and complete exhaustion are responsible for the hallucinations, you can do something yourself: Sleep well and relax, then the hallucinations will also go away.

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