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Definition: dream from Stedman's Medical Dictionary for the Health Professions and Nursing

(drēm) Mental activity during sleep in which events, thoughts, emotions, and images are experienced as real.


Summary Article: dreams
from Chambers Dictionary of the Unexplained

Experiences of images, sounds, sensations and emotions that are not directly due to external stimuli. They normally occur during sleep and are not apparently the subject of conscious control.

There are a wide range of conflicting scientific theories as to how and why dreams occur and, for this reason, there is no universally accepted definition of what constitutes a dream – some admit such concepts as ‘waking dreams’ (which are often offered as an explanation for paranormal experiences; see dreams, waking), ‘daydreams’ and other dream-like experiences into the general category of dreams.

Within the scientific community, dreams are regarded as a normal brain activity which (in very loose and general terms) involves the processing of ordinary sensory information that has previously been received. It used to be believed that they occurred only during phases of sleep known as ‘rapid eye movement’ (REM) sleep – this phase of sleep can be distinguished visually by an external observer due to the obvious movement of the eyeball beneath the eyelid. However, recent research and opinion suggests that the simple fact that dreams are more clearly remembered by subjects when they are woken from REM sleep (as opposed to deep sleep) does not necessarily mean that they are entirely restricted to these phases. Dreams are still the subject of extensive and on-going scientific research.

Two particularly interesting areas of dream research are ‘lucid dreams’ (in which the dreamer is aware that they are dreaming and can often exercise an element of control over the dream) and ‘false awakenings’ (in which the dreamer experiences the sensation of waking up and going about normal routines while they are actually still asleep).

Historically, dreams have been interpreted in a number of different ways and they continue to be the subject of a wide range of paranormal claims. They have been regarded in cultures throughout the world as experiences that result from one of several variations on the theme of the soul, spirit or astral body leaving the physical body during sleep to enter another world or realm. Conversely, they are sometimes used by those who believe that they are a ‘normal’ phenomenon as a counter argument to paranormal explanations for such things as out-of-body experiences.

Perhaps the most widely held paranormal belief relating to dreams is the idea that people can experience ‘precognitive dreams’ (see precognition). Throughout history, dreams have been strongly associated with predicting the future, as illustrated by the Old Testament story of Joseph interpreting Pharaoh’s dream, and the argument over the value of dreams between Chauntecleer the cock and his hen-consort Pertelote in Chaucer’s Nun’s Priest’s Tale. The cincinnati premonition is a modern example of what is alleged to be an accurate precognitive dream. The standard sceptics’ answer to such claims is that, with so many dreams being experienced on a daily basis, there is a strong statistical likelihood that at least some of them will resemble actual future events. See also waking impressions.

© Chambers Harrap Publishers Ltd 2007

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