Things that cause hallucinations
Perception is the ability to capture information from the environment through a set of actions in the form of a stimulus for final learning. It is therefore the result of a process of selection, interpretation and correction.
In many cases, perception deficits are associated with a mental disorder, such as schizophrenia. However, it does not always have to be conditioned to this, because human beings can be, for many other reasons, the victim of a disturbance in their way of seeing and interpreting reality. In the face of this problem, the result (coming from whatever trigger) is common: the experimentation of distortions and deceptions of one’s own mind.
Hallucinations are the most common form of these cases of perceptual impairment. This concept has evolved throughout history, modifying and enriching its definition. In short, the hallucination occurs in the absence of a stimulus that triggers it, but giving the feeling to the sufferer that it is completely real. These can be caused by different reasons: schizophrenia, depression, epilepsy, tumors, substance consumption and even in small moments of stress or anxiety.
There is a wide range of different hallucinations, depending on the sensory modality in which they appear. The four main fields in which it is classified are: visual, auditory, taste and smell hallucinations, and finally, the haptics.
Visual hallucinations occur when the subject sees something that is not real. The distortion ranges from the visualization of small flashes to people, imaginary beings and even lived scenes. Within this modality, some of the most striking subcategories are the "liliputienses", in which the size of what we see does not correspond to what it would look like in reality (for example, a giant bee) or the ²autoscopia[, by which the person can see himself from the outside of his body. These hallucinations are very common with substance use.
The next, auditory, are frequent from schizophrenia. These consist of hearing something that does not exist, from a simple noise to a voice that speaks to us. In many cases, these inner voices order actions to the person.
Hallucinations of smell and taste are the least common, and are often associated with intoxications or neurological disorders. And finally, haptic hallucinations are those produced from touch. It has distinguished itself between active tactile hallucinations, in which the subject believes to have touched non-existent objects and passive, in which the patient believes to have been touched. This can be considered as one of the most traumatic, since those who suffer from it can feel that they are being burned or pricked, among others. On the other hand, there are also cases that experience sexual alterations.
Part of what makes hallucinations so striking is the inability of the one who suffers them to distinguish between fantasy and reality. We review in this gallery what things can cause hallucinations, as well as the most curious syndromes.
Hallucinations are nothing but individual perceptions about a smell, a sound or a vision that does not correspond to any external physical stimulus, that is, they are created by our mind and the only one who sees, smells or hears them, is the one who suffers the hallucination. The most common hallucination is hearing voices when no one has uttered a single word but there can also be hallucinations about hearing footsteps approaching, windows or doors opening, seeing beings or objects that do not exist in reality or feeling the internal movement of organs, for example. But what causes them?
The brain is a delicate organ, so even the smallest anomalies can wreak havoc on the system. A head injury or concussion can cause a brain injury, according to the Mayo Clinic, as well as an aneurysm, cancer or multiple sclerosis, among other diseases. Injuries can affect cognitive function and, in some cases, trauma to the brain’s visual center can lead to hallucinations, according to a study published in the Journal of Clinical Psychiatry.
Shared psychotic disorder or shared insanity is a psychological condition involving a small group of people who find themselves under a collective delusion, a situation that reinforces each other’s paranoid beliefs. These delusions may make us suspect that our partner is cheating on us or imagine that someone is trying to take our lives.
An example of this shared madness was given in a boarding school in Malaysia. A small group of students claimed to have seen a black figure lurking around the school. After that, more students and even teachers claimed to have seen such a figure.
This type of hallucination, in which those affected present a virtually identical psychiatric symptomatic picture, is usually triggered by stress.
Mass hysteria, similar to the previous cause of hallucinations, occurs in larger groups, spreading rapidly, and often includes symptoms of fainting, nausea, and hyperventilation.
Two well-known examples of mass hysteria were the laughing epidemic in Tanzania and the tragedy of Cine Oberdan. As for the first one, it all started with a joke, in 1962. Inexplicably, a joke caused the population of several cities in the Tanganyika region to suffer fits of uncontrollable laughter. Event that didn’t end until 18 months later. This collective laughter caused pain, fainting, breathing problems or skin rashes to the mass victim of this occurrence.
A crack of 'fire! ' in an Oberdan cinema in April 1938 in São Paulo was the trigger of mass hysteria. Panic gripped the spectators and the rush to get out of the building as quickly as possible resulted in the deaths of 30 people who were trampled to death by the crowd. Funny thing is, there never was such a fire.
The most curious cause of hallucinations has to do with visual impairment, whether caused by glaucoma, cataracts, tumors, or other ailments. According to the journal Live Science, Charles Bonnet syndrome is a disease that causes patients with visual loss a series of complex visual hallucinations. Normally these hallucinations consist of seeing faces, cartoons and patterns. This condition is thought to occur because the brain’s visual system is no longer receiving visual information from the eye or part of the retina, and begins to make its own images.
Charles Bonnet syndrome occurs in between 10% and 40% of older adults who have significant vision loss, according to various studies.
It is a rare degenerative brain disorder (about 1 case per million people) that progresses rapidly. It is a prion disease, similar to mad cow disease in animals, which causes neurological damage. People with Creutzfeldt-Jakob disease lose control of their limbs and emotions, and may experience hallucinations when the condition affects the occipital lobe, according to a study published in the journal Journal of Clinical Psychiatry.
A large majority of adults possess the herpes simplex type 1 virus, which usually manifests as an irritating but harmless nuisance (lip sores) and should not be confused with sexually transmitted hereditary genital herpes virus or herpes simplex virus type 2. However, there are rare cases, in any of the types of herpes, which at the point of infection or during reactivation of a previous infection, may cause encephalitis or inflammation of the brain. The National Institute of Neurological Disorders and Stroke points out that when herpes causes encephalitis it can lead to headaches, fever, personality changes and hallucinations.
This neurological syndrome is characterized by bizarre and distorted perceptions of time and space, similar to what was experienced by the protagonist of Lewis Carroll’s story in "Alice’s Adventures in Wonderland". Patients with this syndrome see objects or parts of their body as smaller or larger than they actually are or even in altered form. This rare syndrome appears to be caused by some viral infections, epilepsy, headaches, and brain tumors. Many studies have suggested that abnormal activity in certain parts of the visual cortex that control information about the shape and size of objects can cause these hallucinations.
In this extremely rare psychiatric condition, patients believe they are becoming wolves or other animals. This psychiatric syndrome thus provokes a hallucination in which they can perceive their own bodies differently, and insist on growing skin, sharp teeth and claws of a wolf. Although the case of the wolf is the best known, there have also been patients who believe they are transforming into dogs, pigs, frogs or even snakes. According to a study published in the journal History of Psychiatry, clinical lycanthropy appears in combination with another disorder, such as schizophrenia, bipolar disorder or severe depression.
Patients with Ekbom syndrome, also known as delirious parasitosis, strongly believe that they are infested with parasites that move under the skin. They have symptoms of itching and biting, and in their desperate attempt to get rid of pathogens, they can injure themselves, which can cause real injuries and infections. The cause of these delusions is unknown but several studies have linked it to structural changes in the brain, and some patients have improved when treated with antipsychotic drugs.
Regular and bulk consumption of alcoholic beverages seriously affects the human brain, and in many cases, permanently. When a person is in a period of detoxification he may suffer from different episodes and syndromes that lead to the suffering of auditory, visual and haptic hallucinations.
Alcohol withdrawal syndrome occurs because blood alcohol levels are reduced below the minimum threshold. This causes tremors, anxiety, epileptic seizures and insomnia, and all this often results, precisely in these sensory confusions.
Alcohol alucinosis consists of a psychotic episode caused by intensive alcohol consumption and which subsides when alcohol consumption ceases. Normally, at this point the hallucinations are auditory and sometimes, the affected person suffers from the delusion of persecution (when trying to differentiate the disorders from the reality).
Psychotic depression is a major depressive disorder that is accompanied by delusions and alterations of perception. These usually revolve around the depressive state of the patient, since this, apart from the delusions, presents all the typical symptoms of depression.
Hallucinations are usually less common than delusions, but may occur in more severe cases. The most typical are auditory hallucinations, whose content is related to the mood of the patient: listening to voices that devalue the patient, criticize what he does or even incite them to suicide.
It’s caused by psychotic depression in its most serious state. Cotard or nihilistic syndrome is a phase of total denial of the person. The patient believes that he is suffering from internal putrefaction of his organs, as well as the sensation of being dead or directly, not existing.
It is one of the most common neurological disorders and is usually accompanied by a depressive mood. The prevalence of psychosis is increased in this type of patients, causing them delusions of persecution, thought disorder, disorganized behavior, transient and intense mood changes, followed by auditory hallucinations, largely.
There are different groups of medicines that modify a person’s awareness. This causes episodes of confusion and delirium, affecting the cognitive processes of the affected person. Some of these are opioid-derived analgesics, anticholinergics, anticonvulsants, H2 antihistamines, carbamazepine, etc.
Some kinds of mushrooms and fungi can cause severe hallucinations that last for hours. Stropharia cubensis is a fungus of the stropharia family, which has psychotropic effects. Curiously, this mushroom is not much appreciated, as gastronomically it is not tasty, but it is one of the most potent in terms of psychotropic effects and hallucinogens.
Ketamine is used clinically as a general anesthetic. It is considered a mild anaesthetic, and therefore its use was focused on children and the elderly. Their psychedelic characteristics were discovered after a large number of patients reported how they felt when they came out of the anesthesia.
MDMA is a modification of methamphetamine and has some effects that are similar to those of this compound. It is one of the most common substances in nightclubs and festivals. It can cause hallucinations, but the most dangerous thing of all is overheating the organs because of its stimulating effect. When the body temperature rises too high, some organs may stop working, especially the kidneys, and this can end the life of your consumer.
The effects of this substance were not known until the late 1950s. Lysergic acid diethylamide, or LSD 25, is a potent hallucinogenic. In the 1960s it was largely consumed, promoted by the hippie movement. It works at four different levels: it has effects on mood, interpersonal behavior, sensory and perceptive level and, finally, cognitive level.
Phencyclidine (PCP), or also known as the angel powder’, is another of the many psychedelic substances that cause hallucinations to those who consume it. It was very popular in the 1990s, although its first use, forty years earlier, was an anesthetic. It is a substance that severely affects different regions of the brain and its worst effects can include vomiting, blurred vision, loss of balance, seizures, coma and even death.