Human brains work harder when playing sports against robots, study finds

The team found that the brains of table tennis players react in different ways to human or machine opponents.

With a ball machine, players’ brains tended to struggle in anticipation of the next serve, but found it much easier when facing a human opponent and the obvious cues they give off prior to a serve.

The findings could have implications for sports training, the researchers said, suggesting that human opponents provide a realism that can’t be replaced with machine helpers.

“Robots are getting more ubiquitous. You have companies like Boston Dynamics that are building robots that can interact with humans and other companies that are building socially assistive robots that help the elderly,” said Daniel Ferris, a professor of biomedical engineering at UF.

“Humans interacting with robots is going to be different than when they interact with other humans. Our long-term goal is to try to understand how the brain reacts to these differences.”

The researchers originally began the project with tennis, but the oversized movements - especially high overhand serves - proved an obstacle to the burgeoning tech used in the study.

“We literally scaled things down to table tennis and asked all the same questions we had for tennis before,” Ferris added.

The smaller movements of table tennis still required innovation to compensate for and they had to double the number of electrodes in a typical brain-scanning cap to 120. Each bonus electrode provided a control for the rapid head movements during a table tennis match.

The electrodes were able to capture fine detail of the brain activity of participants while they play a fast-paced game of table tennis and the brain region that turns sensory information into movement was analysed.

“It takes all your senses – visual, vestibular, auditory – and it gives information on creating your motor plan. It’s been studied a lot for simple tasks, like reaching and grasping, but all of them are stationary,” said researcher Amanda Studnicki. “We wanted to understand how it worked for complex movements like tracking a ball in space and intercepting it, and table tennis was perfect for this.”

The researchers analysed dozens of hours of play against both Studnicki and the ball machine. When playing against another human, players’ neurons worked in unison, like they were all speaking the same language.

In contrast, when players faced a ball-serving machine, the neurons in their brains were not aligned with one another which is known as desynchronisation.

“If we have 100,000 people in a football stadium and they’re all cheering together, that’s like synchronization in the brain, which is a sign the brain is relaxed” Ferris said. “If we have those same 100,000 people but they’re all talking to their friends, they’re busy but they’re not in sync. In a lot of cases, that desynchronisation is an indication that the brain is doing a lot of calculations as opposed to sitting and idling.”

The team suspects that the players’ brains were so active while waiting for robotic serves because the machines provide no cues of what they are going to do next. This suggests that human brains process these two experiences very differently and that training with a machine might not offer the same experience as playing against a real opponent.

“I still see a lot of value in practicing with a machine,” Studnicki said, “but I think machines are going to evolve in the next 10 or 20 years and we could see more naturalistic behaviours for players to practice against.”