“I can't even remember what happened that night” is a common joke/cry for help among people who recently drank to the point of blacking out. But there's also evidence that drinking even a little bit can seriously impair learning and memory.
Sleep, especially the REM phase when dreams occur, is when memories get cemented into our minds. Alcohol blocks REM sleep, and as a result, says University of California, Berkeley, professor Matthew Walker, drinking can make you forget new information—even if the drinking happens days after the learning took place.
