A dream.
A dream is a succession of images, dynamic scenes and situations, ideas, emotions, and sensations that usually occur involuntarily in the mind during certain stages of sleep.[1][2][non-primary source needed] Humans spend more than two hours dreaming per night,[3] and each dream lasts around 5–20 minutes.[4]
.jpg)
The content and function of dreams have been topics of scientific, philosophical and religious interest throughout recorded history. Dream interpretation, practiced by the Babylonians in the third millennium BCE[5] and even earlier by the ancient Sumerians,[6][7] figures prominently in religious texts in several traditions, and has played a lead role in psychotherapy.[8][9]Dreamwork is similar, but does not seek to conclude with definite meaning. The scientific study of dreams is called oneirology.[10] Most modern dream study focuses on the neurophysiology of dreams and on proposing and testing hypotheses regarding dream function. It is not known where in the brain dreams originate, if there is a single origin for dreams or if multiple regions of the brain are involved, or what the purpose of dreaming is for the body (or brain or mind).