Close but no cigar, the saying goes. But new research shows that when it comes to gambling, the human brain seems to take a very different approach. In our head, near misses, such as a lottery ticket just one number away from the jackpot, are interpreted as wins.

Using functional MRI, Luke Clark of the University of Cambridge and his colleagues looked at the brains of 15 volunteers who were playing a computerized slot machine. Unsurprisingly, wins activated the players’ reward system, whereas complete misses did not. When the wheel stopped just one position from the pay line, however, the reward system of volunteers’ brains got excited the same way it did after a win—there was much activity in the striatum and the insula, areas involved in reinforcing behavior with positive feedback.

This type of reinforcement makes sense in behaviors that involve actual skill, such as target shooting, because a sense of reward provides encouragement to keep practicing, Clark says. “A near miss in a game of chance doesn’t mean that you are getting better,” he notes, yet it seems that the brain mistakenly activates the same type of reinforcement learning system in these situations.

The findings expose the underpinnings of gambling addiction, according to Clark. Even though all volunteers were nongamblers, those whose brain showed a greater response in the scanner also reported feeling more desire to continue trying after near misses. Excessive recruitment of these reward areas, therefore, may be a risk factor for compulsive gambling, Clark says.

Note: This article was originally printed with the title, "Close Call Counts."