(Photo: Helder Almeida/Veer)

On a crowded city sidewalk, a stranger knocks hard into your shoulder. Aggressive gesture or innocent mistake? In the split second it takes to lock eyes with your might-be assailant, your mind may already have supplied an answer to that question. Many of us, in situations like this, exhibit something called hostile attribution bias: a tendency to err on the side of assuming malevolence in the intentions of others.

For some of us, this social reflex has some practical justification. If you’ve spent time in a threatening environment—a menacing schoolyard, home, neighborhood, or workplace—hyper-vigilance of this sort may be a mechanism to avoid a real chance of getting harassed, punked, or bullied.

The trouble is, the more we sense hostility in others, the more aggressive we tend to be in return. And in many social contexts, hostile attribution bias is, as psychologists put it, highly "maladaptive."

The trouble is, the more we sense hostility in others, the more aggressive we tend to be in return. And in many social contexts, hostile attribution bias is, as psychologists put it, highly “maladaptive.”

Some of us, for instance, see hostility in babies. According to a 2013 study that examined a racially and economically diverse sample of women, mothers-to-be who believe that infants sometimes misbehave—by, say, dirtying their diapers—just to spite their parents were more likely to go on to mistreat, harshly parent, or abuse their own infants and toddlers.

Other forms of violence arise from this reflex as well. Chicago police estimate that 70 percent of the city’s homicides stem not from “strategic” crime (say, planned gang reprisals) but from altercations: heat-of-the-moment conflicts that escalate quickly. Hostile attribution bias, researchers believe, is often the first accelerant. That’s why one recent large-scale intervention with at-risk Chicago teens tried coaching them to analyze their own reactions to perceived threats. It might sound heady, but after just 13 hour-long sessions, participants were subject to almost half the number of violent-crime arrests compared to a control group.

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