Oddly, among the participants asked to recall past successes, those who remembered more examples were willing to take on about 21 percent more credit-card debt than those who remembered fewer. Perhaps, Haws speculated, they struggled to remember all 10 and then questioned their self-control. “They think, ‘If I were that successful, it would be easier for me to recall these successes,’” she said.

But the participants who remembered times when they had failed to rein in their expenditures—regardless of how many instances they recalled—racked up just as much debt as those who reflected on 10 successes. The fact that they had wasted money in the past had little effect on their willingness to do it again.

Seeing yourself as a failure, Haws explained, can get you down. “And when we’re feeling down, we tend to splurge,” she said.

The common proverb intended to counteract mistake making—“just slow down!”—might not help much, either. After making a mistake, our brains typically do slow down the decision-making process the next time a similar issue comes up, through a phenomenon known as “post-error slowing.” However, that doesn’t always make the next decision more accurate.

That’s because our brains rely on poorer-quality evidence from the surrounding environment the second time, according to Roozbeh Kiani, an assistant professor at New York University’s Center for Neural Science. Braden Purcell, a post-doctoral fellow in Kiani’s lab, recently observed this pattern in a study for which he monitored brain activity in humans and monkeys as they made mistakes during a computer game.

The study participants watched a collection of moving dots on a screen, and then used their eyes to indicate the direction in which they thought the majority of the dots were traveling. Both humans and monkeys took longer to make their next decisions after a wrong answer, with the effect more pronounced for difficult choices than for easier ones. The slowness didn’t make them likelier to be right, though, suggesting that the subjects were consistently using weaker information to decide.

The reason for the reliance on worse information might be that “the brain gets involved in a quest to understand why the error took place,” Kiani said. It tries to figure out, why did this error happen? Did something about the world change? Is there something wrong with me? “The negative feedback triggers a cascade of computations,” Kiani said, which distract from the decision at hand.

In the study, this didn’t happen when researchers had subjects wait a

short while before attempting the task again. That pause gave subjects’ brains a chance to recover from the negative feedback. In other words, if you’re playing basketball, and you keep missing baskets, it might be best to try again another day.

In 2008, researchers at McMaster University in Ontario found a similar problem took place with “tip of the tongue” phenomenon. “This can be incredibly frustrating — you know you know the word, but you just can’t quite get it,” the researcher Karin Humphreys told LiveScience at the time. “And once you have it, it is such a relief that you can’t imagine ever forgetting it again. But then you do.”