A fever dream is a vivid and often bizarre hallucination you might experience during a high fever.
It’s thought that when the body’s temperature rises significantly, the brain’s normal functioning can be temporarily altered, leading to intense and surreal perceptions.
Although they can occur during any stage of sleep, most of our vivid dreams happen during rapid eye movement (REM) sleep. It’s speculated that fevers can disrupt our REM sleep, which is why vivid dreams occur.
These dreams may involve distorted images, unusual sensations or fragmented thoughts, and can be quite disorienting.
While fever dreams are typically temporary and not harmful, they can be unsettling.
Ideally, if the fever is controlled, for example with regular paracetamol, or the fever passes, the dreams should settle on their own.
This article is an answer to the question (asked by Ben Middleton, via email) 'What is a fever dream?'.
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