For seasoned pianists, mastering their craft requires years of dedicated practice. Yet even the most accomplished musicians eventually reach a point where further improvement is increasingly out of reach. But what if all it takes to break the plateau is a helping hand?

Researchers in Japan have devised a robotic exoskeleton that can move a pianist’s fingers and play notes for them.

Developed by Shinichi Furuya and colleagues at Sony Computer Science Laboratories in Tokyo, this exoskeleton — previously designed to rehabilitate injured hands — is a major step up skill training.

“I’m a pianist, but I [injured] my hand because of overpracticing,” Furuya told New Scientist. “I was suffering from this dilemma, between overpracticing and the prevention of the injury, so then I thought, I have to think about some way to improve my skills without practicing.”

Robo Prof.

Furuya recalled how his teachers used to guide his hands over the keys, showing him techniques through touch rather than words. That experience led him to wonder: Could a robotic exoskeleton replicate this effect?

The device straps on top of a pianist’s hand, with small motors attached to each finger. It can move each finger independently, flexing and extending the joints up to four times per second. This passive training—where the device moves the fingers without active input from the pianist—proved to be surprisingly effective.

Breaking Through the Ceiling Effect

To test the device, the researchers recruited 118 trained pianists, all of whom had played since childhood for at least 10,000 hours. These were not amateurs looking for a shortcut but seasoned musicians who had already honed their craft to a high level.

Each pianist practiced a challenging piece until they reached a performance plateau—where no additional improvement was observed. Then, they underwent a single 30-minute session with the robotic exoskeleton, which moved their right-hand fingers through different sequences, both simple and complex (index + ring then middle + pinky), at various speeds.

The results were visible. Pianists who received the fast and complex training could move their fingers more quickly, not only in their trained hand but in their untrained hand as well. “Even when the skill plateaued after weeks of piano practice, passive training of the fast and complex motor skill with the robot further facilitated the maximum rate of repetitive piano keystrokes,” the researchers wrote in their study published in Science Robotics.

The improvements were immediate and persisted even a day later. Brain scans suggested that the training altered the sensory cortices, the brain regions responsible for controlling fine motor movements. This means the passive training may have reshaped neural pathways, enabling more efficient coordination of finger movements.

Passive Learning? Sign me up!

Typically, people assume that motor skill improvement requires active effort—playing faster, practicing longer. But this study suggests that passive movement, even without conscious control, can push the brain to adapt in ways that eventually enhance performance.

“It’s a bit counterintuitive why it worked, because you would have thought that actually performing the movements yourself voluntarily would be the way to learn,” says Nathan Lepora of the University of Bristol. “But it seems passive movements do work.”

The most intriguing part of this study was the “inter-manual transfer effect.” Although the exoskeleton only trained the right hand, pianists showed improvements in their left hand as well. This suggests that the benefits of robotic training extend beyond just the fingers being moved—something scientists are eager to explore further.

So… What Else Could We Learn This Way?

The study hints at exciting possibilities beyond piano playing. If robotic exoskeletons can enhance motor skills in musicians, could they be used to improve dexterity in surgeons, artists, or athletes? Could they help people recovering from strokes regain fine motor control more effectively?

“This is the first time I’ve seen somebody use [robotic exoskeletons] to go beyond normal capabilities of dexterity, to push your learning past what you could do naturally,” Lepora told New Scientist.

The researchers acknowledge some limitations. The training sessions were short, and there were signs of muscular fatigue when pianists played at their maximum speed. Still, this is a very impressive demonstration of robotic assistance in skill development.

For now, the robotic exoskeleton remains an experimental tool. But for pianists striving to master their craft, it offers a glimpse of a future where the limits of human ability may no longer be set by their fingers alone, but by the machines that help them move.

The findings were reported in the journal Science.