The team designed their cursor game to be difficult for monkeys but still easy to analyze. Motion capture cameras tracked the movement of the monkeys’ arm, which controlled the dot on the screen. The game itself was the same every time. According to the researchers, any difference in speed, position and accuracy could only come from the one variable tested: the reward.
The monkeys learned to anticipate particular rewards with visual cues on the computer screen – different colored targets corresponded to each reward. Earl and the others excelled in the practice period, when they didn’t win anything for failing or sips for doing it. They performed a little better when the reward they thought was doubled or tripled. If this trend continued, a rare jackpot – a drink 10 times larger than the average reward – should have motivated even better performance. But the jackpot did the opposite. The monkeys performed a lot more unsuccessful races when the huge prize was up for grabs. Earl choked on 11 of his 11 jackpot opportunities.
To find a cause, Adam Smoulder, a graduate student on the team, scrutinized what was going on with the monkey’s arm movements during thousands of trials. Their reaction times and top speeds showed no clear trend. “Really, the only consistency we saw was this increase in to warn“, says Chase.
Imagine the monkey’s arm gestures as a compound of two phases: an initial rapid “ballistic range” movement to bring the cursor closer to the target, followed by a slower and more precise “spotting” step to land on the target. . Earl, Ford and Nelson were repeatedly underrated during jackpot trials. Instead of starting as they normally would, with a quick ballistic range that covered a lot of ground, their range would end short; the rallying step dragged on until time ran out.
“Monkeys choke on being too careful,” Batista says. In humans, psychologists have linked suffocation to payment too much paying close attention to your movements, a behavior called explicit surveillance. Thinking about your movements makes them slower. And he thinks that’s what’s going on; the monkeys run wild and under-exploit. “If it’s not metacognition,” he said, “I don’t know what it is.
One hypothesis as to why big rewards cause choking is that making precise movements depends on a “neural sweet spot” for rewards. The anticipation of a greater reward can cause neurons to release more dopamine. At the right levels, this dopamine helps keep movement sharp. But if motivation jumps, the flood of the neurotransmitter could overwhelm the brain’s communication networks. “Too little reward, we are not very efficient; too much reward, you’re not performing very well, ”says Chase.
The new study doesn’t identify an exact neural cause for choking, but it paves the way for scientists to study high-stakes performance neuroscience with lab animals. In future experiments, having an animal model will make it easier to use electrodes to listen to brain chatter.
“Have they shown that this is the only way humans or animals choke?” No, but it is a way, ”says Beilock. A picture of the underlying systems is important, she says, as multiple regions could be involved, depending on the situation. Assuming these details translate into humans, it could explain how distinct regions of the brain cause distinct types of choking. A failed motor task would be like missing the ball; a failed cognitive task would mean forgetting your answers during a job interview. The brain regions involved in each situation may overlap, but they can also be separate and worth exploring.
Rob Gray, an Arizona State University sports psychologist who studies how pressure affects human performance, says the monkey data looks like a lot as explicit surveillance in choking athletes. “This kind of non-fluid movement is what you expect when you try to consciously control things from above,” he says. It’s paralysis by analysis: “You micromanage your body. “