Oneirology

In the 19th century, two advocates of this discipline were the French sinologists Marquis d'Hervey de Saint Denys and Alfred Maury.

The field gained momentum in 1952, when Nathaniel Kleitman and his student Eugene Aserinsky discovered regular cycles.

Aserinsky noticed that the sleepers' eyes fluttered beneath their closed eyelids, later using a polygraph machine to record their brain waves during these periods.

[11] The discovery that dreams take place primarily during a distinctive electrophysiological state of sleep (REM), which can be identified by objective criteria, led to rebirth of interest in this phenomenon.

When REM sleep episodes were timed for their duration and subjects awakened to make reports before major editing or forgetting could take place, it was determined that subjects accurately matched the length of time they judged the dream narrative to occupy with the length of REM sleep that preceded the awakening.

This close correlation of REM sleep and dream experience was the basis of the first series of reports describing the nature of dreaming: that it is a regular nightly occurrence, rather than an occasional phenomenon, and that it is a high-frequency activity within each sleep period occurring at predictable intervals of approximately every 60–90 minutes in all humans throughout the life span.

[citation needed] Dream reports can normally be made 50% of the time when an awakening occurs prior to the end of the first REM period.

This increase in the ability to recall appears to be related to intensification across the night in the vividness of dream imagery, colors and emotions.

[citation needed] The definition of dream used in quantitative research is defined through four base components: In summary, a dream, as defined by G. William Domhoff and Adam Schneider, is "a report of a memory of a cognitive experience that happens under the kinds of conditions that are most frequently produced in a state called 'sleep.

In theory, old memories having undergone synaptic efficacy refreshment multiple times throughout one's lifetime result in accumulating errors that manifest as illusory dreams when stimulated.

One such successful connection was made to the olfactory system, influencing the emotions of dreams through a smell stimulus.

[17] Though there is much debate within the field about the purpose of dreaming, a leading theory involves the consolidation of memories and experiences that occurs during REM sleep.

Links to post-traumatic stress disorder (PTSD) and dreaming have been made in studying the flashbacks or nightmares the victims would suffer.

Measurement of the brain waves exhibited by the subjects experiencing these episodes showed great similarity between those of dreaming.

The drugs used to treat those suffering from these symptoms of flashbacks and nightmares would suppress not only these traumatic episodes but also any other sort of dreaming function.

[2] The symptoms of schizophrenia involve abnormalities in the perception or expression of reality primarily focused on delusions and hallucinations.