When we perform an action and get an unexpected reward, we learn to repeat that action. And in the presence of others competing for resources—food, money, and so on—our competitors’ actions offer opportunities to guide our behavior. According to new work from researchers at the University of Bristol in England, it is not our peers’ successes that stick with us, but their failures.

Volunteers played a simple game, modeled after foraging in the wild, against a computer-controlled com­petitor. Players chose one of four boxes, which paid out varying sums of money. To maximize winnings, a player had to occasionally sample each of the boxes. When players saw their competitors get an unexpectedly high sum, functional MRI scans showed no measurable brain activity in reaction. When the drones got an unexpectedly low payout, however, parts of a player’s brain associated with inhi­bition went bonkers.

Learning from competition, then, “is not learning to act like your competitor, it is learning not to act like your com­petitor when they fail,” explains Paul Howard-Jones, who co-led the study with Rafal Bogacz.

Howard-Jones notes that while the computer was making its move, which simply consisted of one box changing color, the player’s mirror neuron sys­tem—which is known to respond to the actions of others—was active, as if the player was making the same choice. When that action led to failure, the inhibitory areas put an immediate stop to the mental simulation. Howard-Jones says this is the first time that researchers have seen people show a mirror neuron response to an action performed by a computer (the players were aware that their opponent was simply software).

Marco Iacoboni, a mirror neuron expert at the University of California, Los Angeles, who was not involved with the study, cautions that fMRI’s resolution is not fine enough to distinguish whether the neurons firing are mirror neurons or just motor cortex neurons, which fire both when we think about an action and when we actually perform an action. Even if the computer is simply recruiting a player’s motor neurons, however, that is still a compelling finding. “It’s really a mechanism for why we anthro­po­morphize pretty much everything,” Iacoboni says. “We tend to mentalize even things that we know have no mind.”