Researchers say your spinal column might be able to process some information that was previously thought to be done by the brain.
Many of us understand that most decision-making and actions originate in the brain.
But it might be time to rethink this notion.
There are circuits that are part of our nervous system that travel down the spinal column and control some relatively simple things, including the pain reflex in people as well as some motor functions in animals.
Now, from Western University in Canada has indicated the spinal cord may also be able to process such complex functions as the positioning of a hand in external space.
“This research has shown that at least one important function is being done at the level of the spinal cord and it opens up a whole new area of investigation to say, ‘what else is done at the spinal level and what else have we potentially missed in this domain?’” said Andrew Pruszynski, PhD, the study’s senior and supervising researcher and an assistant professor at Western’s Schulich School of Medicine & Dentistry and Canada research chair in sensorimotor neuroscience, in a statement.
This kind of hand control requires sensory inputs from multiple joints, mainly the elbow and the wrist. These inputs were previously thought to be processed and converted into motor commands by the brain’s cerebral cortex.
By measuring the lag, or latency, in the response, the researchers were able to determine if the processing was actually happening in the spinal column or the brain.
There are a number of possible uses for this research.
Among them are the treatments for disabilities using spinal communication.
This potential for rehabilitative advances intrigues people in the field.
Dr. Robert L. Masson, medical director of the NeuroSpine Center of Excellence at Orlando Health Central Hospital, said the anatomical connections have been known for decades.
“All sorts of pathways bypass the brain — or the thinking brain. There are a lot of autonomic pathways and new ways to use robotics,” Masson told Healthline. “There has been no way to bridge the gap between the brain and the injured part of the body.”
“With an exoskeleton, [injured people] can use limbs that couldn’t before,” he explained.
People who are paraplegic won’t be walking tomorrow, he noted, despite videos showing people who are disabled walking.
“It’s crucial to maintain optimism. The technology needs to grow, but solutions are on the horizon,” Masson said.
“Even if there isn’t a remedy right in front of them, you have to keep the body tuned,” he said. “Doing exercise, keeping strong and flexible.”
It’s a way to ensure that when the technology is ready, the patient will be prepared to take advantage of it.
“A fundamental understanding of the neurocircuits is critical for making any kind of progress on rehabilitation front,” said Pruszynski, who’s also a scientist at Western’s Robarts Research Institute and the Brain and Mind Institute. “Here we can see how this knowledge could lead to different kinds of training regimens that focus on the spinal circuitry.”
Researchers at Western’s Brain and Mind Institute used a specialized robotic technology, a three degree of freedom exoskeleton.
Study participants were told to maintain their hand in a target position.
Then, the robot bumped it away from the target by simultaneously flexing or extending the wrist and elbow.
The researchers measured the time that it took for the muscles in the elbow and wrist to respond to the bump from the robot. They wanted to see whether these responses helped bring the hand back to the initial target.
“What we see is that these spinal circuits don’t really care about what’s happening at the individual joints,” Jeff Weiler, PhD, a postdoctoral fellow at Schulich School of Medicine & Dentistry and the study’s lead researcher, said in a statement.
“They care about where the hand is in the external world and generate a response that tries to put the hand back to where it came from,” he explained.
The response generated by the spinal cord is called a stretch reflex and has previously been thought to be limited in terms of how it helps movement.
“Historically, it was believed that these spinal reflexes just act to restore the length of the muscle to whatever happened before the stretch occurred,” said Pruszynski. “We are showing they can actually do something much more complicated — control the hand in space.”
Perhaps in the future, we won’t only refer to others as brainiacs, but “spineacs” as well.