Ever been in a high-pressure situation where you had to perform but completely tanked? You’re not alone. Experiments on monkeys show that “choking” under pressure is linked to a decrease in activity in the neurons that prepare for movement.
As per Stevan Chase, a neuroscientist at Carnegie Mellon University in Pittsburgh, Pennsylvania, we see this activity almost everyday, in all types of sports, and outside the sport activities as well. Chase and his team looked into what happens in the brain that causes performance to crash and published their findings in Neuron.
Choking under pressure is not limited to humans. As a tennis player might miss a match winning shot, monkeys can also tank in high-reward situations.
Methodology
The team set up a computer task where rhesus monkeys received a reward after moving a cursor quickly and accurately over a target. Each trial gave the monkeys cues as to whether the reward would be small, medium, large or ‘jackpot’. Jackpot rewards were rare and big, creating a high reward situation.
Using a tiny chip implanted into the monkeys’ brains with electrodes, the team monitored how neuronal activity changed between reward scenarios. The chip was placed in the area which controls our movement, known as the motor cortex, an area of the frontal lobe.
They found that in jackpot scenarios the activity of neurons associated with motor preparation decreased. Motor preparation is the brain’s way of calculating how to do a movement — like lining up an arrow on a target before releasing it. Researchers observed underperformance by monkeys as their brains were under-prepared due to a drop in their motor preparation.
“It helps us understand how reward-outcome mediated behaviour is not linear” says Bita Moghaddam, a behavioural neuroscientist at Oregon Health & Science University in Portland.
“You just don’t perform better as the reward increases,” Moghaddam says. It would be interesting to see how other brain regions respond in jackpot-reward situations as well, she adds, because multiple regions could be involved.
Peak preparedness
The team then looked into why motor preparation decreases in high-stakes situations. An analysis of how reward motivation and neural preparation was related to the monkeys’ performance showed that as the size of the reward increases, neural activity reaches a peak. For even bigger rewards, preparedness starts to decline and the brain is pushed out of its performance sweet spot. The researchers call this the neural biassed hypothesis.
