Newborn babies spend a significant amount of time (50% -90%) in REM sleep, the sleep stage in which most dreams occur. This suggests that dreaming plays a role in early brain development and information processing. Studies have shown that REM sleep increases the likelihood of the infant remembering the information provided in the learning exercise in utero. It is interesting to note that fetuses are able to generate electrical brain waves similar to adults, and may even develop sleep-wake cycles while in the uterus. Additionally, researchers have proposed a theory that the vivid and complex REM dreams of newborns may be important for brain development, specifically in the acquisition of language and social cognition, through the process of active forgetting of unimportant details and the consolidation of important memories.