A bus company in China has launched a new “safe driving” campaign by suspending bowls of water over their drivers. To avoid getting wet, drivers must drive gently. In today’s technology-obsessed world, this solution is elegantly primitive. You might imagine that this simple yet ingenious idea was conjured by someone functioning at their very best, that such “aha insights” come when innovators are at their peak.

Not so. A recent study by Mareike Wieth and Rose Zacks suggests that innovation and creativity are greatest when we are not at our best, at least with respect to our circadian rhythms. Circadian rhythms determine whether you are a “morning-type” person or an “evening-type” person, and are often measured with a short paper-and-pencil test called the Morningness-Eveningness Questionnaire. Circadian rhythms drive daily fluctuations in many physiological processes like alertness, heart rate and body temperature. Recent research indicates that these rhythms affect our intellectual functioning too.

Numerous studieshave demonstrated that our best performance on challenging, attention-demanding tasks - like studying in the midst of distraction - occurs at our peak time of day. When we operate at our optimal time of day, we filter out the distractions in our world and get down to business.

In a study I conducted, for example, participants were given three related cue words (e.g., SHIP OUTER CRAWL), and were required to find their common link (SPACE). When misleading distractors were presented with the cue words (e.g., SHIP-ocean OUTER-inner CRAWL-baby), those tested at non-optimal times were more likely to be misled by the distractors and showed lower solution rates. Those tested at peak times were not affected by the distraction. In this and related studies, peak-time benefits are most robust when distraction would disrupt our thought processes and cause errors.

But distraction is not all bad, and Wieth and Zacks have demonstrated that we can use our increased susceptibility to distraction at off-peak times to our advantage. In their study, they asked participants to solve analytic problems and insight problems at peak or off-peak times. Analytic problems generally require people to “grind out a solution” by systematically working through the problem utilizing a consistent strategy. Here is a classic analytic problem: “Bob’s father is 3 times as old as Bob. They were both born in October. 4 years ago, he was 4 times older. How old are Bob and his father?” No innovation or creativity necessary to solve this problem; one simply has to work it out mathematically.