It seems that the primate brain is inherently wired with a sense of “choking,” which only emerges under the right circumstances. Researchers are delving deeper into this peculiar emotion.
Sitting in a dimly lit room at a research center in Pennsylvania, Earl gestures to the left. Slowly lifting and lowering his arm, Earl simultaneously monitors the position of the red dot on the computer screen in front of him. Wherever Earl places his hand, the red dot appears on the screen. Earl signals to the dot, trying to guide it to a vibrant color zone on the screen, just as he has done in thousands of trials before. He eagerly thinks about the reward he would earn upon success, but alas: time is up!
Earl, a rhesus monkey under pressure, fails to move the red dot to the target area before time runs out.
Choking, often referred to by gamers as “choking under pressure,” is the phenomenon where pressure causes you to fail when trying to achieve a goal. In football, it’s the penalty shot that sails into the stands; in interviews, it’s when you start rambling nonsense in front of a top executive; choking is the paradox that makes you overanalyze a situation while forgetting crucial details, leading to a disconnect between the brain and the body it controls.
Shooting the ball out of the goal during a penalty kick is one of the many manifestations of “choking.”
“You think too much; you put too many things in your head,” says Steven Chase, a biomedical engineer at Carnegie Mellon with a deep expertise in movement research.
Choking is a common experience, yet the mechanisms produced by the brain behind this phenomenon remain a mystery. Which brain waves or chemicals explain the feeling of “choking”? Which part of the brain is involved? Scientists have proposed various theories based on human behavior and brain imaging. However, to conduct neuropsychological tests with electrodes placed around the head to measure brain activity, researchers first need to observe this phenomenon in laboratory animals.
They are conducting trials on three rhesus monkeys—Earl, Nelson, and Ford—simply observing the monkeys’ movements through a camera. The new research findings: the team provides the first evidence that humans are not the only primates who choke under pressure. The scientific report has been published in PNAS.
The team suggests that the behavior is triggered by the opportunity to receive a significant reward, and the analysis from the expert team lists several potential explanations for why choking occurs. In the tests with the red dot on the screen, the monkeys must demonstrate speed and accuracy in moving the dot into the designated area.
The trend indicates that the greater the reward, the higher the performance in action. Each time they fail, the monkeys are not punished, but each time they succeed, they receive a sip of water. However, when faced with the opportunity for a larger reward—a full day’s worth of drinking water—the monkeys struggle in tasks they would typically excel at.
Rhesus monkey.
Proving the existence of “choking” in other species is not only fascinating but also adds significant value to the field of cognitive research. “This opens up a new research opportunity,” says Sian Beilock, a cognitive neuroscientist and author of a book on choking. “If we can understand the underlying mechanisms, we may be able to devise ways to alleviate this feeling.”
“Before this research emerged, it was just a peculiar experience seen in humans,” comments Aaron Batista, a biomedical engineering expert and co-author of the new study. But with a preliminary model of the mechanisms behind choking, researchers can decode the brain’s signals during stressful situations; similar to how athletes struggle when close to failure, or how the brains of disabled individuals control prosthetic limbs with their thoughts.
Historical research on the brain has suggested that the feeling of “choking” exists only in humans, emerging from a brain with complex connections. But if other animals can also choke, perhaps this is a mechanism that has always existed in all brains.
The brain, whether human or that of an unthinking animal, produces thoughts and signals to the muscles while pursuing significant rewards. If unique rewards generate rare brain signals, the training and evolutionary path cannot eliminate this peculiarity; large rewards do not occur frequently enough for the brain to become accustomed to handling pressure.
The research team designed their game to be challenging enough for the monkeys but still simple enough for analysis. Cameras track the monkeys’ hand movements as they navigate the red dot on the screen. Since the monkeys will only play one game, any differences in their performance each time will stem solely from the single variable: the reward after each round.
The monkeys gradually learn to recognize the reward signals through different colored squares on the screen. Earl and the other monkeys excelled in the training phase, successfully playing without rewards. When a sip of water turned into several gulps, the monkeys’ performance improved slightly. Logically, a reward ten times the first sip of water would allow the monkeys to achieve the highest performance in the trials.
Contrary to expectations, the large reward put the monkeys into a choking state. Earl failed in all 11 trials.
After analyzing thousands of instances of monkey hand movements, research student Adam Smoulder sought to uncover the reasons. He found that the monkeys’ reaction times and speed of hand movement showed no trends, but there was one factor that caused their performance to decline: they were much more cautious.
In trials with moderate rewards, the monkeys’ hand movements were clearly divided into two phases: one was a strong swing to quickly bring the red dot closer to the colored area, and the other was a slow action to gradually move the dot toward the target. With the large reward, all three monkeys in the experiment failed. Instead of swinging their hands as they usually did to shorten the distance the red dot had to travel quickly, they moved their hands slowly and ran out of time before the red dot reached the colored square.
“The monkeys choked because they were too cautious,” researcher Batista said. In humans, psychologists link the feeling of choking to focusing on every detail of one’s own movements, a behavior known as explicit monitoring. Thinking about how the limbs move can slow down actions. Batista believes this is the feeling the monkeys experienced when they failed: they lost sight of their goal and did not achieve the significant reward.
Another hypothesis related to choking: precise movement relies heavily on dopamine released by the brain, which is produced from the state of anticipation for a large reward. At reasonable levels, dopamine helps the limbs move more accurately, but with increasing rewards, the excitement can overwhelm brain signals. Researcher Chase notes that both excessively large and small rewards have the potential to impact performance.
Lukas “gla1ve” Rossander, one of the most accomplished CS:GO players in e-sports history, still faces the “choking” emotion while competing.
The new research does not pinpoint the exact reasons behind choking, but it lays the groundwork for other scientists to study brain activity in high-pressure situations.
“Is this the only way to show that both humans and animals choke? No, but it indicates that this is one of many ways,” researcher Beilock stated. It sketches out mechanisms hidden deep within a very important structure, as we do not yet know how many brain regions are involved in this sensation. Missing a shot is a failure of the limb, while giving a wrong answer to the final question of Who Wants to Be a Millionaire is a failure of cognition; the choking phenomenon occurs in both cases, but it remains unclear whether one or multiple brain regions are involved. This is a worthy issue for further research.
For researcher Chase, neuroscience related to choking is not necessarily a study that brings despair. Humans sometimes choke, but the promise of a large reward generates strange signals in the brain that affect bodily function. Identifying this is the first step toward eliminating it.
Now we know that not only humans experience “choking.” Researchers are seeking ways to apply this truth to more practical outcomes, such as prosthetic limbs for disabled people. “Since emotions can affect limb movement, it will be a factor that prosthetic manufacturers need to pay attention to.” A mechanical arm capable of filtering out disruptive signals in the brain to perform the right actions would be highly effective.
