Illusions Health Dictionary

A distorted sensation based on misinterpretation of a real stimulus (for example, a pen is seen as a dagger). It is differs from a hallucination, in which a perception occurs without any stimulus.Usually, illusions are brief and can be understood when explained. They may be due to tiredness or anxiety, to drugs, or to forms of brain damage. Delirium tremens is a classic inducer of illusions. imaging techniques Techniques that produce images of structures within the body. The most commonly used and simplest techniques are X-rays (to view dense structures such as bone) and contrast X-rays, in which a medium, such as barium, that is opaque to X-rays is introduced into the body. Contrast X-ray techniques include barium X-ray examinations (used to examine the oesophagus, the stomach and the small intestine); cholecystography (used to visualize the gallbladder and common bile duct); bronchography (to view the airways connecting the windpipe to the lungs); angiography and venography (to provide images of the blood vessels); intravenous urography (to visualize the kidneys and urinary tract); and ERCP (by which the pancreatic duct and biliary system are examined).

Many X-ray imaging techniques have been superseded by newer procedures. These include ultrasound scanning, MRI (magnetic resonance imaging), PET scanning, and radionuclide scanning. However, X-rays are used in CT scanning. Some of these techniques use computers to process the raw imaging data and produce the actual image. Others can produce images without a computer, although one may be used to enhance the image. imipramine A tricyclic antidepressant drug most commonly used as a longterm treatment for depression. Possible adverse effects include excessive sweating, blurred vision, dizziness, dry mouth, constipation, nausea, and, in older men, difficulty passing urine.... illusion

Linn.

Family: Agaricaceae; Amanitaceae.

English: Fly Agaric (mushroom), Aga, Soma.

Ayurvedic: Identified as Soma of Rigveda (controversial). (Sushruta described 24 varieties of Soma and 18 other drugs as its substitutes.) Intensely poisonous; used for intoxication.

The fungus has been used in Russia for preparing an intoxicating drink.

Toxic principles arecholine, mus- carine and mycetoatropine (muscari- dine). Muscarine stimulates postgan- glionic, cholinergic and neuroeffector junctions. The isoxazole constituents are psychoactive.

2-4 Fly Agaric (more than 10 g fresh) are toxic; 20 (more than 100 g fresh) are lethal. (Francis Brinker.)

A. pantherina is used in Japan for intoxication.

Aga is not a true hallucinogen. The illusions are a misinterpretation of sensory stimuli due to isoxazole, ibotenic acid, muscimol, muscazone and traces of muscarine. (Natural Medicines Comprehensive Database, 2007.)... amanita muscaria

A condition of altered consciousness in which there is disorientation (as in a confusional state), incoherent talk and restlessness but with hallucination, illusions or delusions also present.

Delirium (confusion) In some old people, acute confusion is a common e?ect of physical illness. Elderly people are often referred to as being ‘confused’; unfortunately this term is often inappropriately applied to a wide range of eccentricities of speech and behaviour as if it were a diagnosis. It can be applied to a patient with the early memory loss of DEMENTIA – forgetful, disorientated and wandering; to the dejected old person with depression, often termed pseudo-dementia; to the patient whose consciousness is clouded in the delirium of acute illness; to the paranoid deluded sufferer of late-onset SCHIZOPHRENIA; or even to the patient presenting with the acute DYSPHASIA and incoherence of a stroke. Drug therapy may be a cause, especially in the elderly.

Delirium tremens is the form of delirium most commonly due to withdrawal from alcohol, if a person is dependent on it (see DEPENDENCE). There is restlessness, fear or even terror accompanied by vivid, usually visual, hallucinations or illusions. The level of consciousness is impaired and the patient may be disorientated as regards time, place and person.

Treatment is, as a rule, the treatment of causes. (See also ALCOHOL.) As the delirium in fevers is due partly to high temperature, this should be lowered by tepid sponging. Careful nursing is one of the keystones of successful treatment, which includes ensuring that ample ?uids are taken and nutrition is maintained.... delirium

False perceptions arising without an adequate external stimulus, as opposed to illusions, which are misinterpretations of stimuli arising from an external object. Hallucinations come from ‘within’, although the affected individual may see them as coming from ‘without’. Nevertheless, they may occur at the same time as real perceptions, and may affect any sense (vision, hearing, smell, taste, touch, etc.).

Causes They may be the result of intense emotion or suggestion, sensory deprivation (for example, overwork or lack of sleep), disorders of sense organs, or disorders of the central nervous system. Although hallucinations may occur in perfectly sane people, they are more commonly an indication of a MENTAL ILLNESS. They may be deliberately induced by the use of HALLUCINOGENS.... hallucinations

Derived from the Mexican peyote cactus, Anhalonium lewinii, this is a hallucinogen used for many centuries by Indian tribes in Mexico as an intoxicant to produce ecstatic states for religious celebrations. In recent times its ability to produce temporary psychotic symptoms has been used to investigate the mechanism of PSYCHOSIS. Mescaline has similar effects to those of LSD: changes in mood and thought, illusions, self-absorption and an altered perception of time. Experience of the drug may subsequently provoke panic attacks, deliberate self-injury, real psychosis and sometimes addiction (see DEPENDENCE).... mescaline

A derangement of the MEMORY in which words are used without a comprehension of their meaning; it is also applied to illusions of memory in which a person in good faith imagines and describes experiences which never occurred to him or her.... paramnesia

n. the process by which information about the world, as received by the senses, is analysed and made meaningful. Abnormalities of perception include *hallucinations, *illusions, and *agnosia.... perception

a personality disorder characterized by cold aloof feelings, eccentricities of behaviour, odd ways of thinking and talking, and occasional short periods of intense illusions, hallucinations, or delusion-like ideas.... schizotypal personality disorder

The flowering tops and dried leaves of the Indian hemp plant CANNABIS SATIVA, containing the active ingredient (tetra-hydrocannabinol). The leaves are usually smoked but can be drunk as tea or eaten in food. Physical effects of marijuana include dry mouth, mild reddening of the eyes, slight clumsiness, and an increased appetite. The main subjective feelings are usually of calmness and wellbeing, but depression occurs occasionally.Large doses may cause panic, fear of death, and illusions. In rare cases, true psychosis occurs, with paranoid delusions, confusion, and other symptoms, which usually disappear within a few days. Regular use of marijuana may lead to a more permanent state of apathy and loss of concern (a condition that is known as amotivational syndrome).... marijuana

n. a false sensory perception of something that is not really there; the perception is subjectively convincing but lacks an external stimulus. Hallucinations may be visual, auditory, tactile, gustatory (of taste), or olfactory (of smell). They may be provoked by mental illness (such as *schizophrenia or severe anxiety disorders), *personality disorders, or physical disorders affecting the brain (such as temporal lobe *epilepsy, sepsis, acute organic syndrome, or stroke) or they may be caused by drugs, alcohol, or sensory deprivation. Hallucinations should be distinguished from dreams and from *illusions (which are misinterpretations of real stimuli). A substantial minority of the population experiences hallucinations not caused by mental illness. Some hallucinations are not always pathological: hypnagogic hallucinations occur in the state between wakefulness and sleep, and the images are often very distinct; these hallucinations occur in 30–60% of patients with *narcolepsy. Hypnopompic hallucinations occur in the state between sleep and full wakefulness; like hypnagogic hallucinations, the experiences may be very vivid.... hallucination