Research Reveals How Brains Can Control Same Motion under Different Circumstances

Join Our Community of Science Lovers!

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

Professional hockey players can make taking the perfect slap shot look easy, whether it's on the ice during a championship game or in a casual game of street hockey. But how their brains can adapt these motor patterns to different situations¿such as wearing heavy protective equipment or not¿remains a neuroscience puzzle. Behavioral studies suggest that the brain's neural processes use internal models to predict and generate commands for movement based on characteristics of the body and its environment. Currently, two competing theories could explain how these models work. Either a single controlling entity can adapt to any load applied to the body and generate a command, or else multiple controllers exist, each capable of responding to a small set of load situations. A report published today in the journal Nature may help resolve this question. Scientists report that neuronal activity in the brains of monkeys seems to act in a highly structured manner as a single controller.

Paul L. Gribble and Stephen H. Scott of Queen's University in Ontario outfitted monkeys with a robotic sleeve that applied independent forces to their shoulders and arms as they carried out a task. While the animals performed the movement under different conditions, the scientists recorded brain activity in their primary motor cortexes, regions involved in motor control. According to the report, the same neurons responded to pressure applied to both the elbow and the shoulder, even though the forces were administered separately. What is more, how neurons responded to forces applied to a single joint could be used to predict how they would react to a burden shared by two joints. The findings, the authors conclude, "may explain why training on simpler tasks can be transferred and improve performance on related, more complex tasks."

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American