When: The Scientific Secrets of Perfect Timing

by Daniel H. Pink

Two American psychologists, Mareike Wieth and Rose Zacks, presented this and other insight problems to a group of people who said they did their best thinking in the morning. The researchers tested half the group between 8:30 a.m. and 9:30 a.m. and the other half between 4:30 p.m. and 5:30 p.m. These morning thinkers were more likely to figure out the coin problem . . . in the afternoon. “Participants who solved insight problems during their non-optimal time of day . . . were more successful than participants at their optimal time of day,” Wieth and Zacks found.21 What’s going on? The answer goes back to those sentries guarding our cognitive castle. For most of us, mornings are when those guards are on alert, ready to repel any invaders. Such vigilance—often called “inhibitory control”—helps our brains to solve analytic problems by keeping out distractions.22 But insight problems are different. They require less vigilance and fewer inhibitions. That “flash of illuminance” is more likely to occur when the guards are gone. At those looser moments, a few distractions can help us spot connections we might have missed when our filters were tighter. For analytic problems, lack of inhibitory control is a bug. For insight problems, it’s a feature.