When we're little and learning how to walk, we stumble and fall all the time. When we do, we pitch out our hands to cushion our fall; if we slip, we instinctively try to propel ourselves forward to not fall on our back.
For Olympic ice skaters, however, that instinct must be changed: They flip on ice, jump into the air, and balance on a single skate while spinning. Earlier this week, Mirai Nagasu became the first American woman to nail a triple axel in Olympic history; on Thursday night, Vincent Zhou's first move in the short program was a casual quadruple lutz, a move no ice skater had ever cleanly landed in Olympic history (his quad flip was a bit less smooth).
These skills are not normal for humans.
"Part of the puzzle is about how a figure skater is able to do these acrobatic moves," Nathaniel Sawtell, a neuroscientist at Columbia University's Zuckerman Institute, told The Daily Beast. "If we did the same thing, our instinct when we slip backwards is to lunge forward so we don't fall."
So Sawtell and his colleague at Columbia University's Zuckerman Institute, Rui Costa, decided to study what it is about figure skaters that makes them able to ignore the part of the brain telling them that being on ice is a slippery, dangerous business.
Sawtell's laboratory focuses on the cerebellum—the back of the brain that coordinates muscle movement. "My lab focuses on the detailed circuitry [of the cerebellum] in a variety of different creatures and how the synapses talk to each other and relay back interesting functions about sensory processing," Sawtell explained. In particular, Sawtell looks at motor control and motor learning—skills that are important for a person balancing on a thin blade of metal on ice.
Costa, on the other hand, researches what in the brain justifies the idea that "practice makes perfect." "We study how repeating actions work," he said. Costa's lab considers the role of the basal ganglion, a structure that sits at the base of the forebrain that is akin to a major highway junction, connected to some other key parts of the brain: the cerebral cortex, thalamus, and brainstem. It's been shown to be important in memory and habit learning, which are key not only to doing routines but also remembering basic skills in figure skating.
Combine the two—practice and somehow resisting falling on your face—and you have essentially the core of figure skating.
Sawtell's research has looked at animals to understand how the vestibular organs in the inner ear—which help provide us the balance to walk and stand and yes, even balance on a pair of metal blades—work to make skaters ignore the instinct to fall. In a normal non-skater, when a person is pitching backwards a signal is sent down the spinal cord to activate the muscles to stiffen and lean forward to counteract the backwards pitch and prevent from falling.
That whole domino effect of signals and pitching back and forward is something that skaters don't really have. "Part of practicing is suppressing or canceling out that reflex," Sawtell said. "Somewhere else in the brain, the motor command is, 'I want to flip backwards' [when they're pushing their body forward]. The command [skaters] are giving themselves cancels reflex activity—and that's not something you can do without practice."
Sawtell thinks that the cerebellum's synaptic connections are somehow altered over the course of time.
It's not that that reflex is completely gone, though: If a skater were pushed on ice or fell, the reflex jumps into action. But when a skater is flinging themselves forward into jumps and spins, that reflex is somehow snuffed out.
When figure skaters practice their routines, they're actually doing a lot of cognitive work. "For figure skaters, just to perfect each of the movements and cancel out the reflex is a lot of work," Costa said. Think about learning a step sequence; it might take a few tries. A piano chord can take a bit longer. Ice skating takes longer than that. And to do the quads that American figure skater Nathan Chen is famous for? Years and years of practice.
"It's really amazing," said Costa, who's been watching the Olympics avidly. "It takes years for someone who is good to do a double jump, then to do a triple jump, then to incorporate additional elements.
"Once you start it, you don't need to think about it. This is the type of thing that for figure skaters can take a lifetime."
In a weird way, ice skaters are able to make fighting the reflex... a reflex.
There's a lot we don't quite understand about how this rewiring in the brain works, where practice nullifies a reflex to fall in favor of balancing without getting rid of it. Costa's research suggests that this skill might stay intact at later ages, with only some diminishing. "For people in physical therapy, they could use these tricks to regain balance and maybe cancel out [the reflex to fall]," he said. In the future, understanding this reflex to see how older, retired former skaters fare with falling will be crucial
None of this can really be proven in humans. After all, "We can't really study figure skaters and look at their cerebellum," Sawtell pointed out. "We can't say for sure. We can only extrapolate from similar tasks done in laboratory animals."
Still, the reflex that's subdued to the point of becoming its own reflex is something that is interesting to study. Neither Sawtell nor Costa think it's necessarily useful for physical therapy, because of the amount of practice required. But Sawtell said that he's been watching Olympic snowboarding and that the reflex mechanism he and Costa describe seems to appear there as well.
Costa says the animals filling in as human substitutes provide fascinating insight. "We use simplistic versions in our laboratory," he said. "How long it takes and the mechanism it takes to get to that level is like whoa!"