September 24, 2026

Mapping how the brain organizes movement

Movement depends on brain circuits that link intention, sensation and action. A new study by Silvia Arber’s team at the FMI and the Biozentrum of the University of Basel, together with their collaborators at the Allen Institute, provides the most detailed map yet of the mouse motor cortex — a brain region involved in controlling movement. The findings could help researchers better understand conditions that affect these circuits, including amyotrophic lateral sclerosis and dementia.

Every movement we make — from reaching for a cup to turning our head — depends on the brain combining information about the body, the surroundings and the action we want to perform. But researchers are still working out how the brain regions that control movement are organized.

In mice, standard brain atlases typically divide the motor cortex into broad primary and secondary regions, based on differences in connectivity. A new study from Silvia Arber’s team at the FMI and the Biozentrum of the University of Basel, together with collaborators at the Allen Institute, reveals a much finer level of organization. The researchers identified 16 distinct subregions, each defined by its own pattern of connections with other parts of the brain. The map provides a more precise framework for studying how movement is controlled and how motor-cortex circuits may be affected in disease.

Mapping motor circuits
Antonio Falasconi and Harsh Kanodia from Arber’s team, together with their colleagues, analyzed 547 experiments tracing how signals travel from different parts of the motor cortex to other brain regions. This allowed them to compare connections with areas involved in movement, sensation and decision-making.

Areas with similar connection patterns clustered into 16 subregions arranged in three rows. Their organization followed two main directions. From back to front, the map shifted from areas more strongly connected to sensory regions, which process information such as touch and body position, toward areas linked to planning and decision-making. From side to side, the subregions corresponded broadly to different parts of the body, from the trunk and limbs to the face and mouth.

The team tested the map in two additional ways: by tracing individual neurons and by examining the types of cells found across the cortex. Both approaches supported the same 16-subregion organization.

Motor cortex blueprint
The researchers also found that the primary and secondary motor cortex send coordinated signals to the brainstem and spinal cord, suggesting that the two regions may operate more in parallel than in the strict hierarchy often assumed.

“The most fascinating finding is the extremely high precision with which the motor cortical modules interact with the output regions and that the modules communicate to the rest of the cortex using the same wiring logic,” Arber says.

The study drew on the Allen Institute’s Mouse Brain Atlas, which provided anatomical reference data and tools for comparing connections across the brain. The new motor-cortex map is also available through BrainGlobe, giving researchers a common framework for aligning their own data.

“Researchers interested in the cortex now have an accessible unified map to align their data to, and this will accelerate progress in the field,” Falasconi says.

The findings could also provide a basis for comparing motor-cortex organization across species, including humans. “Bringing together vast datasets describing the brain's wiring and its cellular makeup, we discovered a valuable and much more precise underlying blueprint of motor cortex organization,” Kanodia says.

Beyond movement research, the map could help scientists study conditions involving motor and frontal brain circuits, such as amyotrophic lateral sclerosis and frontotemporal dementia, by identifying which subregions and connections are especially vulnerable.