UCSD - University of California - San Diego

10/14/2026 | Press release | Distributed by Public on 10/14/2026 09:11

Neurobiologists Trigger Learned Movements by Activating Just 20 Brain Cells

Published Date

October 14, 2026

Article Content

Key Takeaways

  • Scientists identified and activated a small group of neurons responsible for the initiation of learned movements.
  • The study, started by a scientist who tragically died in 2023, used cutting-edge techniques to not only "read" brain activity down to the level of individual cells, but "write" patterns that allowed researchers to control movement.
  • The discovery settles a longstanding question of whether brain patterns are the controller of learned motor skills or simply a passive reflection.

When learning how to perform new movements, our brains etch the details in our minds as we master the new task.

From a young child learning to play the piano to a novice pickleball player getting familiar with the sport's paddle strokes, our brains inscribe neurological activity patterns as we acquire new motor skills.

Previously, neurobiologists have documented distinguishable patterns of activity in the motor cortex of the brain that emerge when we learn such specific movements. But aspects that have remained unclear include whether such patterns are responsible for generating the movement or if they simply reflect the movements driven by other regions of the brain. Additionally, is the patterned activity generated in the motor cortex or inherited from elsewhere?

Holographic optogenetics enables researchers to switch on precisely selected neurons with light while observing how the rest of the network responds.

University of California San Diego scientists now have an answer. Studying mice, the researchers used advanced optical methods and other techniques to analyze brain activities in unprecedented detail. The researchers isolated the specific area responsible for newly learned movements and stimulated a handful of neurons there to produce the movement, resulting in a type of "mind-reading" and "mind-control" through neuron recording and stimulation.

"We found that briefly activating only about 20 carefully selected neurons in the motor cortex could trigger the larger pattern of brain activity associated with a learned movement and, in many cases, produce the learned movement itself," said senior author Takaki Komiyama, a professor in UC San Diego Departments of Neurobiology (School of Biological Sciences) and Neurosciences (School of Medicine). "Considering that the mouse brain contains approximately 70 million neurons, it is surprising that such a small-scale stimulation can drive specific large-scale brain activity and behavior."

The study, published in the journal Nature, was led by Biological Sciences graduate student Qiyu Chen and is based on research led by An Wu, an assistant project scientist in the Komiyama laboratory who tragically died in a Montreal fire in 2023.

During the study, the researchers implemented a combination of cutting-edge research techniques including two-photon calcium imaging for ultra-precise visuals of brain activity as well as a holographic optogenetic method to stimulate neurons. The advanced methods allowed the researchers to perform experiments to "read" brain activity and "write" in specific patterns down to the level of individual cells that enabled them to control movement.

As they recorded the brain signals of mice learning new movements, the researchers hypothesized that the activity identified in neurons that exhibited elevated levels of activity immediately before the animals made the movement, or "early-onset neurons," would initiate the newly learned movement. The authors tested whether an artificial stimulation of these neurons could induce learned movement.

"We observed that the stimulation of early-onset neurons can trigger movements," the researchers confirmed in the study. Further, they found that the success of producing the learned movement depended on the state of the motor cortex immediately before stimulation and whether the mouse being tested was engaged with the task at hand.

"The new technologies allowed us to read the activities of hundreds of neurons and write new activity into it so we can have control over the activity," said Chen. "This gives us the advantage of being able to observe the activity of neurons during a specific behavior. We can identify the functional properties of neurons and then follow that up by selectively stimulating the neurons of our choice."

The research continues in the Komiyama Lab with a follow-up project that seeks to investigate the connections between the key neurons. They would like to learn how the neurons are "talking" to each other to produce the learned movements.

Such research could one day help in various diseases as scientists develop brain-computer interfaces to help stroke and paralysis patients. Learning how neurons associated with movement are coordinated could eventually help elicit specific movements for daily life activities. Further, the ability to imprint specific activity in the brain could be leveraged in the future to promote learning and restore memory.

Professor Takaki Komiyama and graduate student Qiyu Chen in the lab with a collection of images featuring An Wu, an assistant project scientist who sadly died in 2023. Wu initiated the research published in the new Nature study.

Neuronal activity in motor cortex is tracked as mice perform a learned motor skill.

The paper was authored by Qiyu Chen, An Wu, Bin Yu, Soyoung Chae, Zijing Tan,

Assaf Ramot, Johnatan Aljadeff and Takaki Komiyama. "We cherish our memories of our dear friend and colleague, An Wu, and dedicate this manuscript to her surviving parents, Mr. Wu and Ms. Qu," the authors note in the paper.

The research was supported by the National Institutes of Health (grants R01 NS125298, R01 NS091010, R01 DC018545 and R01 MH128746); the National Science Foundation (grant 2024776); and the Simons Collaboration on the Global Brain Pilot Award.

Read more news about: School of Medicine, Health Innovation

UCSD - University of California - San Diego published this content on October 14, 2026, and is solely responsible for the information contained herein. Distributed via Public Technologies (PUBT), unedited and unaltered, on October 14, 2026 at 15:11 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]