Neurons in the Brain Function as Traffic Lights, Regulating Each Movement
Deep within the brain, neurons in the Substantia Nigra pars reticulata (SNr) of the basal ganglia have been revealed to exhibit an astonishingly precise control over movement initiation and suppression, according to a recent study published in the journal Nature. This momentous finding challenges the long-held view that these neurons only function as a sort of "brake."
Led by Professor Silvia Arber, researchers from the University of Basel and the Friedrich Miescher Institute for Biomedical Research investigated the nature of these neurons in mice. Contrary to the belief that they merely fire to inhibit movement, they discovered that these neurons display highly dynamic patterns—individually synchronous and precisely timed to the movements taking place.
This study presents a picture of a highly complex and organized system, where individual SNr neurons either increase or decrease activity depending on the specific movement phases, such as reaching, grasping, and retracting. The result is that the basal ganglia sends out "traffic light" signals, allowing and disallowing individual movements in real time, thus enabling complex motor behaviors to emerge.
Remarkably, even the slightest changes in movement are accompanied by precise adjustments in SNr signaling. This suggests that the basal ganglia has a highly specific, movement-based coding system—far more granular than a simple "go" or "stop" mechanism.
The implications of this research are profound for the understanding of Parkinson's disease and other movement disorders. In Parkinson's disease, for example, the delicate balance of movement control in the basal ganglia is disrupted, causing difficulties in initiating movement. It is hoped that these insights will pave the way for more targeted treatments, as researchers now have a better understanding of how to restore the natural dynamic control of movement in these patients and improve the efficacy and reduce the side effects of existing therapies.
The study, Dynamic basal ganglia output signals license and suppress forelimb movements, was authored by Silvia Arber et al.
Sources:- University of Basel- Nature- Image credit: Our website
[1] Arber, S., Falasconi, A., Kanodia, H., Murillas, A., Donato, A.A., Hellmich, M., Rajasekaran, J., Spaink, H.P.J.M., Obrisil, T., and Berneston, AR. (2025). Dynamic basal ganglia output signals license and suppress forelimb movements. Nature. [Abstract]
[5] Olanow, C.W. (2020). Parkinson's disease. The Lancet. [Full text]
- This newly discovered control of movement initiation and suppression by neurons in the Substantia Nigra pars reticulata (SNr) challenges conventional neuroscience beliefs about their function, as previously thought, they only acted as a "brake."
- The study, 'Dynamic basal ganglia output signals license and suppress forelimb movements,' led by Professor Silvia Arber, revealed the intricate timing and synchronization of SNr neuron activity, offering a more granular understanding of their role in health-and-wellness and neurological-disorders like Parkinson's disease.
- The findings suggest that the basal ganglia has a highly specific, movement-based coding system, rather than a simple "go" or "stop" mechanism, providing compelling neuroscience news for the medical-conditions community and potentially leading to more targeted treatments for Parkinson's disease and other movement disorders.
- In Parkinson's disease, the disturbance in the delicate balance of movement control within the basal ganglia presents difficulties in initiating movement, with researchers now well-equipped to develop more effective treatments to restore natural dynamic control, ultimately reducing side effects and improving therapy efficiency.
