visual hallucination

Thân thiện

A patient describes a visual hallucination of a small, colorful bird in the room.

Definition

Noun: * A false visual perception; something seen that is not actually present: A visual hallucination is a sensory experience where a person sees an image, object, or pattern that does not exist in the external world. It is a type of illusion created by the mind, often associated with neurological conditions, psychiatric disorders, sleep deprivation, or the effects of certain substances.

Usage

• The term is primarily used in medical, psychological, and psychiatric contexts to describe a specific symptom.
• It is a countable noun (e.g., , ).

Examples

• The patient reported visual hallucinations of swirling colors and geometric patterns.
• A common visual hallucination in Charles Bonnet syndrome is seeing detailed faces or figures.
• High fever can sometimes trigger brief visual hallucinations in children.
• The neurologist asked if the visual hallucinations were accompanied by any other sensory disturbances.

Advanced Usage

• Clinical Description: Visual hallucinations can be described as (e.g., flashes of light, shapes) or (e.g., seeing fully formed people, animals, or scenes).
• Pathophysiology: In medical literature, the mechanism behind a visual hallucination is often discussed in relation to specific brain regions, such as the occipital or temporal lobes.

Variants and Related Words

• Hallucination (n): The broader category of false sensory perceptions, which can be auditory, olfactory, gustatory, tactile, or visual.
• Illusion (n): A misinterpretation of a real external stimulus (e.g., mistaking a coat on a chair for a person), which is distinct from a hallucination where no stimulus is present.
• Phosphene (n): The sensation of seeing light caused by pressure on or stimulation of the eye (e.g., rubbing your eyes), which is a physiological phenomenon rather than a psychiatric hallucination.

Synonyms

• Phantom vision
• Pseudohallucination (in specific clinical contexts, referring to a hallucination the person knows is not real)

Antonyms

• Accurate perception
• Real visual stimulus

Học thuật

Noun

1. illusory visual perception