Oneirology is the scientific study of dreams. Current research seeks correlations between dreaming and current knowledge about the functions of the brain, as well as understanding of how the brain works during dreaming as pertains to memory formation and mental disorders. It’s not exactly a dream interpretation, because it studies the process of dreams instead of analyzing the meaning behind them.

It took its beginning in the 19th century with two 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. A further development was brought by Kleitman and William C. Dement exploring the particular period of sleep, in which the eyes dart about actively. This kind of sleep became known as rapid eye movement (REM) sleep, and Kleitman and Dement's experiment found a distinct correlation between REM sleep and dreaming.

Research into dreams includes exploration of the mechanisms of dreaming, the influences on dreaming, and disorders linked to dreaming. Work in oneirology overlaps with neurology and can vary from quantifying dreams, to analyzing brain waves during dreaming, to studying the effects of drugs and neurotransmitters on sleeping or dreaming. The knowledge gained in this area could have implications in the treatment of certain types of mental illnesses. It can help us learn about the meaning of our dreams and explain why we have nightmares.