If you're going over notes for today's presentation or memorizing the names of your child's classmates' parents before the
school open house tonight, do it early in the morning, when your immediate recall is highest. For longer retention (the book
club meets in three weeks, but this weekend's your only chance to finish The Good Nanny), evening is better. "This is just the way the brain is organized," says Smolensky. "Memory depends on nucleic acids, and
those show circadian rhythms." In other words, your brain doesn't store information with the same efficiency all day; there
are peaks and valleys. "College students often unknowingly take advantage of the dual circadian rhythm by staying up late
studying, then doing a quick review the morning of the exam," says Smolensky.