are thoughts, emotions, or sensations experienced during sleep.
Some dreams are remembered upon awakening; others may not be.
It is thought that dreams occur during the portion of sleep
called rapid-eye movement (REM) sleep,
which may occur at intervals during a sleep episode.
Some psychologists believe that dreams have psychological importance,
and may reflect issues that are of importance to the dreamer.
Some neuroscientists believe that dreams have importance in
the process by which experienced events are transferred to long-term
memory, a process called consolidation.
Further reading: "The Remains
of the Day"
by Catherine E. Myers. Copyright © 2006 Memory Loss and the Brain