Visual hallucinations are disorders of visual perception characterized by the formation of visions in the absence of a real object. Elementary visual images are represented by sparks, flashes, spots. Simple hallucinations are static objects that do not change shape and are unambiguously interpreted by the patient. Complex hallucinatory visions are plot pictures, one or more characters that can move, increase or decrease, inspire ideas. Examination of patients is carried out by the method of observation and conversation, with the help of provocative samples. Symptomatic therapy involves taking antipsychotics.
general characteristics
Visual hallucinations are the second most common after auditory ones. They are perceived as real objects, so the behavior of patients is determined by the content of false perceptions. Hallucinating patients may stare at empty walls for a long time, brush off the vision, avoid it, bypass it, changing the original route. Unlike memories, fantasies, ideas, hallucinations arise spontaneously, without a cause, regardless of the will of the patient. They cannot change or be expelled by an act of will (like unpleasant thoughts).
Another feature of visual hallucinations is the projection of images outward. True hallucinations are assimilated with real objects, for example, insects are perceived as crawling on a wall. Another type of symptom is pseudo-hallucinations. They are perceived as something anomalous, subjective, do not have the properties of objective reality, arise without any reason, are of a violent or obsessive nature, intertwined with delusional ideas of influence. Pseudo-hallucinatory images are projected in the subjective space - in front of the eyes, on the side of the gaze. They can decrease when approaching, increase when moving away.
According to the content, visual hallucinations are elementary - smoke, fog, flashes, lightning, sparks; simple - static simple objects; complex - dynamic phenomena, united by some idea. Simple and complex hallucinations are divided into zoopsic (images of animals), polyopic (many identical visions), demonomaniac (images of mythological characters), panoramic, scene-like, endoscopic (seeing objects inside the body), autovisceroscopic (seeing one's own internal organs).
Causes of visual hallucinations
Visual hallucinations are more characteristic of organic lesions of the brain, namely, the occipital and temporal lobes of the cortex, the rostral parts of the trunk, and the thalamus. They are also a frequent companion of a clouded confused consciousness, a hypnotic or half-asleep state. The content of the images is varied, but neurological causes often provoke true-type hallucinations, and psychotic and hypnotic states - pseudo-hallucinations. Causes include extreme exposure, organic brain damage, mental illness, acute intoxication.
Intense stress factors
The causes of passing single hallucinatory influxes are a state of acute physical or mental stress. Extreme situations that threaten a person's life lead to changes in the functioning of the brain. Factors affecting the mental state can provoke visions with increased suggestibility and impressionability - psychological readiness to see something related to experiences, but not existing in a real environment. How stressful causes are considered:
- Impact of critical temperatures. A decrease or increase in body temperature is accompanied by a change in the blood supply to the brain - the body seeks to maintain the constancy of the internal environment, regulates heat transfer, constricting or expanding blood vessels. Visual hallucinations appear with hypothermia, when the body temperature drops to 35 ° C, with hyperthermia with a body temperature of 39 ° C and above. The state of hallucination does not last long, is accompanied by disorientation, confusion, disruption of the functioning of vital organs.
- Deprivation of physiological needs. Critical conditions can act as the causes of hallucinatory visions, in which a person is unable to satisfy basic physiological needs - food, water, sleep, rest. Blurry images begin to be seen on the 8th-9th day of fasting, on the 2nd-3rd day without water (up to about 10% of body fluid is lost). The critical phase of sleep deprivation is 4 days, when irreversible life-threatening processes occur, apathy increases, abulia occurs, and hallucinatory symptoms unfold.
- Lack of sensory stimulation. The human nervous system is able to function normally when receiving a variety of information from the outside - with stimulation of the senses. Sensory deprivation - partial or complete isolation from external influences. Its causes are the loss of the analyzer, staying indoors without light, sounds, vibrations. Sometimes such a state is created artificially with the use of derivation chambers, baths. In the absence of external visual stimuli, the brain begins to compensate for the lack of information by creating visual hallucinations.
- social isolation. Visual hallucinatory images are formed as a result of prolonged forced or specially organized loneliness (hermitage). This phenomenon has been studied in most detail on the examples of prisoners in solitary confinement cells. They have elementary auditory, visual hallucinations (flashes of light, screams, noises) provoked by sensory deprivation, as well as complex dynamic images - "friends", "mentors", "saviors". They contact the prisoner with glances, silent decrees, words.
- Psychological trauma. Possible causes of visual hallucinatory symptoms are psychotraumatic situations. The first pathogenetic mechanism is associated with situations of loss of loved ones, places or events to which a person was attached. Hallucinatory images "return" what was lost. Another mechanism is based on post-traumatic experience: the emotions of fear, anger, horror were not experienced in a critical situation, so a person involuntarily returns to it through thoughts, dreams, visual hallucinations. Example: An ex-military man suffering from PTSD "sees" explosions shooting at opponents.
Neurological diseases
Visions in neurological patients occur with local and diffuse brain lesions. Visual images can be provoked by pathological irritation of the zones responsible for receiving and processing visual information. This type of disorder is characterized by elementary images - photopsies. In addition, visual hallucinations are sometimes included in the structure of the hallucinatory-delusional symptom complex, the syndrome of clouded consciousness. The most common causes of visions:
- Dementia with Lewy bodies. The disease is diagnosed in patients aged 65-7 years, characterized by a change in the structure of the neurons of the cerebral cortex. Typically, the onset is with a triad of symptoms including extrapyramidal disorders, dementia, and visual hallucinations. Most often, hallucinatory images develop, which have a clear color, shape, size, volume. A typical sign of this type of dementia is the rapid disappearance of visions when the patient tries to interact with them.
- Alzheimer's disease. The basis of the pathology is the process of neuron death, loss of synaptic connections in the cortical zones and subcortical regions of the brain. Visual hallucinations are likely at the second stage of the disease, when there is a noticeable deterioration in everyday, professional activity, the process of constructing a speech statement is disrupted, and it becomes impossible to perform arbitrary actions. Hallucinatory symptoms manifest themselves in the context of a delusional syndrome, often accompanied by anxiety, fear, and panic.
- Parkinson's disease. The disease proceeds with the progressive death of neurons that produce the neurotransmitter dopamine. With a mild (outpatient) form of the disease, psychosis develops in about 20% of patients, with a severe one - in 65%. The psychotic state is manifested by unmotivated fear, absent-mindedness, insomnia, hallucinatory-paranoid symptoms, and disorientation. As the causes of psychosis in Parkinson's disease, the rapid progress of the pathology and the use of drugs aimed at alleviating motor dysfunctions are considered.
- Traumatic brain injury. TBI includes bruises and concussions, barotrauma, skull injuries. With focal lesions of the occipital regions, visual hallucinations are represented by elementary forms: zigzags, flashes in one half of the field of view. Hallucinatory-delusional psychoses often develop in men after moderate and severe injuries. They appear many years later, in a remote period. Visual hallucinations are formed before psychosis against the background of twilight, delirious or oneiric changes in consciousness. In a psychotic state, auditory pseudohallucinations occur more often.
- Cerebral vascular pathologies. Diseases of the vessels of the brain (atherosclerosis, arteritis, hypertension) lead to a deterioration in the blood supply to its individual sections, diffuse organic lesions. Neurological symptoms are represented by headaches, dizziness, vomiting, perception disorders, and speech disorders. Patients see flashes, sparks, flashes. Visual phenomena unfold during an exacerbation of the disease, accompanied by disorientation in space, general weakness.
- Tumors of the brain . Clinically, neoplasms of the brain are manifested by focal and cerebral symptoms. The causes of visions are neoplasias localized at the junction of the frontal and temporal lobes. Visions occur as part of paroxysmal disorders - short-term hallucinatory influxes without delirium. The critical abilities of the patient remain relatively intact, after a certain duration of the disease, he begins to understand that the visible images are a symptom of the spread of the tumor.
Mental disorders
Visual hallucinations develop in psychotic states of various origins. Exogenous psychoses are characterized by true hallucinatory images, endogenous - pseudohallucinations. In both cases, there is an emotional and behavioral inadequacy of the patient, a decrease or complete absence of a critical attitude towards his condition. Common psychotic causes of hallucinations:
- symptomatic psychoses. This group includes infectious psychoses, psychotic conditions provoked by endocrinopathies, vascular pathologies, acute intoxication with PAS, alcohol. The stupefaction of consciousness proceeds in the form of a oneiroid - a dream-like disorientation with detailed pictures of fantastic pseudo-hallucinatory experiences intertwined with reality. The content is usually adventurous, fabulous, less common. Visual hallucinations are colorful, mobile, massive. Patients either actively participate in visions or remain observers.
- Schizophrenia-like disorder. Common causes of the disease are head injuries, neuroinfections, epilepsy. With organic delusional disorder, visual hallucinations predominate, and not auditory hallucinations, as in schizophrenia. Their content is often related to the theme of delirium, reflecting scenes of a mystical or religious nature. Hallucinatory-delusional syndrome is manifested by inappropriate behavior, impulsiveness, emotional excitability.
- Schizophrenia. This disease is characterized by auditory hallucinatory phenomena. Visual hallucinatory disorders unfold less frequently, they are dimly expressed, inconsistent, flickering in fragments, reminiscent of visions. Often their purpose, content, causes are completed by the patient on the basis of delusional ideas, information from hallucinatory voices. If schizophrenia has developed as a result of taking psychoactive substances, “flashbacks” appear - pictures from the past.
Acute period of intoxication
The state of acute intoxication develops after the introduction of a large dose of a psychoactive substance. It leads to impaired consciousness, deterioration of cognitive activity, distortion of perception. The behavior and emotions of people become inadequate, uncontrollable. There is no critical attitude to one's own state. Visual hallucinations are most likely to occur with poisoning by the following substances:
- Drugs. Common causes of visions are the use of hallucinogens, volatile solvents, cannabis preparations. When intoxicated with hallucinogens, the world begins to seem brighter, objects - painted in unusual colors. Visual hallucinations are elementary and scene-like, more often true. Substance abuse with the use of volatile solvents is manifested by impaired consciousness with acute hallucinosis, delirium, or oneiroid. Hallucinatory pictures are bright, plot. The use of cannabinoids provokes visions that are brighter than the real world, present with open and closed eyes.
- Medicines . Visual hallucinations as part of delirious stupefaction are manifested in case of poisoning with diphenhydramine, atropine, antidepressants. When taking large doses of psychostimulants, an intoxication paranoid develops, which includes delusions, visual and other types of hallucinations. There is a risk of the formation of manic-like states with euphoria, motor disinhibition, accelerated thinking.
- Alcohol. Delirium tremens occurs when drinking stops in patients with stage II-III alcoholism. Alcoholic delirium is manifested by delirium associated with hallucinatory images of various modalities. Visions are usually threatening, appear in the form of unpleasant and dangerous creatures - demons, devils, creeping reptiles. The state of psychosis, psychomotor agitation during intoxication is a common cause of self-harm.
Diagnostics
The diagnosis is made by a psychiatrist. The patient's family members are the first to notice the presence of deviations in his behavior. The patient himself is often uncritical to visions, perceives them as part of reality. The states with emotionally colored images - frightening, surprising, annoying - are most quickly detected. If the hallucination is constant and does not disturb the patient, then the symptom sometimes remains undiagnosed for several years. The examination is carried out by the following methods:
- Conversation. The doctor does not ask direct questions about the presence of hallucinations, but reveals them in the process of communicating with the patient. Since visions are bright, unusual, cause fear and other experiences, they often become the subject of discussion. Sometimes the psychopathological nature of the described phenomena is obvious, in other cases the doctor needs clarifying information from relatives.
- observation. Patients with visual hallucinations may peer into an empty space in front of them, look at an empty wall. Sometimes, for no apparent reason, they turn to the side or look back if the image appears at the periphery of the visual field. Examining the vision that has arisen is accompanied by an unstable emotional state: the appearance of anger, fear, surprise.
- Pathopsychological tests. To identify perceptual disorders, special provocative tests are used. Visual hallucinations can be detected during the Reichardt test: the patient is asked to tell what is shown on a piece of paper that is actually clean. Another variant of the provocation is the Lipman test: pressure on the eyelids can cause visions.
Treatment
With intoxication and stressful effects, hallucinations are of a passing nature, so it is enough to eliminate their causes: stop taking a drug or medicine, prevent exposure to extreme factors. Hallucinatory manifestations in neurological diseases and psychoses are stopped with the help of antipsychotic drugs. They reduce psychomotor agitation, suppress delusions and hallucinations.