MADRID, FEBRUARY 12 (EUROPE PRESS) –
We often believe that our brain is at the center of complex motor function and control, but how intelligent is the spinal cord? It turns out that it's smarter than we think, according to new research from the University of Western Ontario ("Western"), in Canada.
It is well known that the circuits in this part of the nervous system, which travel along our spine, apparently control simple things such as human pain reflexes and certain motor control functions in animals. Now, this work has shown that the spinal cord can also process and control more complex functions, such as the position of the hand in outer space.
"This research has shown that at least one important function is performed at the spinal cord level and opens a new research area to say," What are we doing at the spinal level and what have we missed in this area? "says senior researcher and supervisor of study Andrew Pruszynski, assistant professor of Schulich School of Medicine and Dentistry of Western and Canadian Research Professor of Sensomotor Neuroscience.
The study, "Spinal reflexes, supports effective manual control", is published in the digital edition of the journal Nature Neuroscience. This type of manual control requires sensory input from multiple joints, mainly the elbow and wrist, and previously it was thought that these inputs were processed and converted into motor commands by the brain's cortex.
Using specialized robotics, an exoskeleton with three degrees of freedom at the Brain and Mind Institute of Western, subjects were asked to hold their hand in the target's position, and then push the robot away from the target by bending or extending wrist and elbow at the same time. Scientists measured the time it took for the muscles of the elbow and wrist to respond to the robot's stroke and if those responses helped the hand to return to the original target.
VERTEBRAL CIRCUITS GENERATE ANSWERS
By measuring the latency or "delay" in the response, they could determine whether the treatment took place in the brain or spinal cord. "We found that these responses happen so fast that the only place where they could be generated is in the spine itself," said study director Jeff Weiler, postdoctoral fellow at Schulich Medicine & Dentistry.
He adds, "What we see is that these vertebrate circles do not really care about what is happening in the individual joints; they care about the hand in the outer world and they give an answer that tries to put their hand back in their place."
This response generated by the spinal cord is called "stretch reflex" and has previously been considered very limited in terms of how the movement helps. "Historically, it was thought that these spinal reflexes only work to restore muscle length to what happened before the stretch occurred," Pruszynski said. "We show that they can really do something much more complicated: control the hand in space."
This discovery greatly contributes to our understanding of neuroscience and neurosurgery and provides new information and goals for the science of rehabilitation. "Understanding Neurocytes is fundamental to making some kind of progress on the rehabilitation front – says Pruszynski, who is also a researcher at Robarts Research Institute of Western and at Brain and Mind Institute – here we can see how this knowledge can lead to different types of exercise plans. that focuses on the lumbar circles. "