Here in the world of chiropractic, the spine and spinal cord have always held our attention. The steady advancement of research shows us that when we adjust the spine, we change the structure and function of the brain. We may see cortical drive to the muscles and reaction times improve. We may also restore joint position sense and increase proprioception. These are documented findings in the world of chiropractic. But where does the spinal cord end, and the brain begin? To many a neurology-buff, they are but one unit.
While chiropractic researchers have had their eyes firmly fixed on what happens in the brain when we adjust the spine, the world of non-chiropractic research has made an interesting discovery that may be applicable to our field: that the spinal cord is smarter than once thought.
A recent study, titled “Spinal stretch reflexes support efficient hand control,” will feature in journal Nature Neuroscience . The study had participants engage with specialised robotics technology (a three degree of freedom exoskeleton) and were asked to maintain their hand in a target position. The robot then bumped the hand out of position and the participants had to bring their hand back.
“By measuring the latency – or ‘lag’ – in the response, they were able to determine whether the processing was happening in the brain or the spinal cord.” In an a press release from the University of Western Ontario, lead researcher Jeff Weiler said, “We found that these responses happen so quickly that the only place that they could be generated from is the spinal circuits themselves. What we can see, is these spinal circuits don’t really care about what’s happening at the individual joints – 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 .”
The stretch reflex generated by the spinal cord was, up until this point, thought to be a lot more limited. This study offers new indications that it can actually control the hand in space, a fact which adds greatly to the existing understanding of neurocircuitry. This is a factor that could be significant for rehabilitation purposes, according to the study’s authors .
While the study clearly exists outside of the chiropractic paradigm, it does provide interesting insight into the organ we are most concerned with: the brain and spinal cord. If what we do increases the health, mobility and optimal function of the spine, then it’s easy to see a potential connection between chiropractic and improving the spinal stretch reflex.
It remains unproven, as it has not yet been researched, and it would certainly be interesting to see a study that brought chiropractic adjustments into the mix. But this latest research certainly provides solid rationale for us to ensure the spine and spinal cord are functioning optimally.