Researchers at Western University, Canada suggests that spinal cord turns out to be smarter as it can perform some complex functions of the hand. This study was published in the Nature Neuroscience on 11 February 2019.
Our circulatory system produces two circuits in the human body. These circuits travel down the spine and control pain reflexes in humans and also some motor-control functions in animals.
The study discovers that the spinal cord can process and perform more complex functions like the positioning of your hand in external space.
To control the positioning of your hand, sensory inputs from multiple joints is required. Previously it was assumed that these inputs arise from the brain’s cerebral cortex. During the experiment, it was discovered that the spinal cord plays a part in the process.
The experiment consisted of using robotic technology. In which people were asked to maintain their hand in a target position while a robot bumped it away from the target by extending the wrist and elbow.
Researchers observed the time that the muscles in the wrist and elbow took to respond to the bump caused by the robot. They also investigated that if the response further helped bring back the hand to the initial set target.
By measuring the time interval between the stimulation and response, the researchers were able to find out whether the processing was happening in the spinal cord or brain.
According to Jeff Weiler, the study’s lead author says that the response happened so quickly that they could be generated from the spinal circuits. This response generated from the spinal cord is called stretch reflex.
Previously it was believed that stretch reflex used to act to restore the length of the muscle to whatever happened before the stretch. But now it is discovered that spinal cord can do something more complex.
Andrew Pruszynski, Schulich School of Medicine and Dentistry professor also the senior researcher of the study said, “This research has shown that at least one important function is being done at the level of the spinal cord. 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?’”
This research provides new information and targets for rehabilitation science. It further contributes to the understanding of neuroscience and neurocircuitry.