If you want to get smarter, you could read more, try certain kinds of brain training, or learn study techniques suggested by science (or geniuses). Or, if you're feeling lazy today, you could just rearrange your schedule.

That's the surprising and useful assertion of bestselling author Daniel Pink in a recent interview about his new book, When: The Scientific Secrets of Perfect Timing, on the Quiet Revolution blog. Questions of when -- when to wake up, when to marry, when to tackle specific tasks -- order our days and lives, and according to Pink also have a surprisingly big impact on our performance.

You're dumber in the afternoon.

You're probably intimately familiar with the peaks and valleys of your own daily pattern of energy and sloth. Unless you're a dyed-in-the-wool night owl, chances are you're perkier and early in the day and drag in the afternoon.

Pink's insists you're far from alone in this experience, and that these oscillations between alertness and exhaustion have a far bigger impact than you probably understand. He offers plenty of evidence:

Anesthesia errors are four times more likely at 3pm than at 9am.  Handwashing in hospitals drops considerably during afternoons. Physicians are much more likely to prescribe unnecessary antibiotics....

Research out of Denmark shows that students who take standardized tests in the afternoon score systematically lower than those who take tests in the morning. The effect is equivalent to missing two weeks of school. Research for the Los Angeles Unified School District shows that elementary school students learn more math when they take the subject in the morning.

All of which is interesting if you're a teacher or hospital administrator, but Pink insists anyone can use knowledge of how dumb we become in the afternoons to do better work. "The day has a hidden pattern: a peak, a trough, and a recovery. And doing the right work at the right time can lead to dramatically better results," he tells Quiet Revolution.

Using that fact to your advantage can give you a far larger bump in performance than you probably imagine. "What's amazing--and little noticed--is that time of day explains about 20 percent of the variance in human performance on cognitive tasks," claims Pink.

Or, in everyday language, you can be effectively 20 percent smarter just by shifting around how you schedule your tasks.

What to schedule when

Taking advantage of these rhythms isn't rocket science, according to Pink. You just need to understand the three phases most of us go through in a day (again, night owls, you're a different case and might want to check out the complete interview or Pink's book for alternate advice).

  • Mornings, when our focus and brain power is greatest, should be set aside for "analytic tasks, those that require heads-down focus and attention," Pink instructs.

  • When your energy levels start to slump after lunch, switch over to routine administrative tasks and other assorted donkey work.

  • Then, expect another burst of energy in the late afternoon and early evening that's ideal for creative work.

Rejigging your schedule to accommodate your natural ebbs and flows will give you an instant bump in effective intelligence. Now that's pretty much guaranteed to be easiest and most useful advice on how to get smarter you'll hear today.