Human brain may hold the key to walking again after SCI

Although walking may seem like an innate and straightforward action, it takes many complex processes and different regions of the brain to effect the movements involved. By some estimates, it takes over 200 different muscles to complete the act of walking and they all need to function cohesively so you don’t trip over yourself. While a full understanding of how we walk still eludes researchers, the prevailing view has been that the motor cortex, a region of the brain that controls the planning and initiation of limb movements, directs the body to walk. 

Dr. Michael Fehlings, a Senior Scientist at the Krembil Research Institute in Toronto, Canada and his research team have discovered a network of nerve cells that plays a key role in controlling our ability to walk. The group’s findings challenge conventional perceptions of how the brain instructs and regulates the body while walking.

The findings of Dr. Fehlings’ study suggest that a different region of the brain, the sensory cortex, can also generate commands that trigger walking. This is surprising because the sensory cortex’s main function is to process information on the internal and external environments of the body. For example, the sensation of warm sunlight on your skin is processed by the sensory cortex.

The researchers further found in an animal model that the sensory cortex sends these commands directly to the spinal cord through a relay of nerve cells. This relay is distinct from and operates in parallel with the signalling route of the motor cortex. “Our data support a potential mechanism through which the sensory cortex can directly and efficiently control walking in response to the sensory information that is continuously processing,” says Dr. Fehlings.

Future research will delve into the mechanisms that govern the generation of signals in the sensory cortex to deepen our understanding of how we walk.