A dream is a succession of images, ideas, emotions, and sensations that usually occur involuntarily in the mind during certain stages of sleep.
The content and purpose of dreams are not fully understood, although they have been a topic of scientific, philosophical and religious interest.
Dreams mainly occur in the rapid-eye-movement (REM) stage of sleep—when brain activity is high and resembles that of being awake.
REM sleep is revealed by continuous movements of the eyes during sleep.
At times, dreams may occur during other stages of sleep.
The potential purposes that are derived from years of research and observations are as follows:
• A component and form of memory processing, aiding in the consolidation of learning and short-term memory to long-term memory storage.
• An extension of waking consciousness, reflecting the experiences of waking life.
• A means by which the mind works through difficult, complicated, unsettling thoughts, emotions, and experiences, to achieve psychological and emotional balance.
• The brain responding to biochemical changes and electrical impulses that occur during sleep.
• A form of consciousness that unites past, present and future in processing information from the first two, and preparing for the third.
• A protective action by the brain to prepare itself to face threats, dangers and challenges.