The Brain's Response to Spinal Cord Injury

When I first got SCI, I thought I was losing my mind because my symptoms were variable. Even though my PhD is in neuroscience, one thing neuroscience doesn't do is go into the huge variability of symptoms. Because I'm a sensory quad, scientific information is even more lacking -- sensory quads are rare. I even had a SCI nurse tell me what my symptoms were/should be, which was completely off the mark. In light of this thread, with Lara posting about ascending (posterior/afferent/dorsal) vs descending (anterior/efferent/ventral), what people should notice is that afferent input affects efferent output. First, there is sensory then there is motor. Put your hand to a hot stove and the first thing is sensory (sensation of hot surface) -- this results in a motor output (motor -- remove hand from hot surface). I had a hard time walking not because of anterior/motor damage but because my posterior/sensory was damaged (did not get accurate information about my body's position in space). This made me look like I was drunk beyond belief. In fact, when I first got my injury, which was metabolic as opposed to traumatic, a lot of people thought I was drunk and they did not realize my spinal cord was being destroyed. People who knew me well, however, called 911. The ER did not do MRIs or do lumber punctures. Furthermore, they did not do blood blood tests that would clue them in on what was going on. Waisted time there. What is particularly horrible about this, is if they did things correctly, they could have halted my spinal cord damage and even REVERSED it. By the time I got to the MAYO, the MAYO concluded it was too late to do treatment. However, about a year later, my new doctor started treatment -- it took 4 months but it began to make a difference because what was really going on was an underlying autoimmune disorder that was not being treated, which in turn, was destroying my spinal cord. About 5% of SCIs are non-traumatic (meaning, not an accident, a fall, etc.). There is an organization within the brain and spinal cord such that if it is not necessary for the brain to be involved, the signals are dealt with solely in the spinal cord. This allows for a quicker response time to things that do not require higher order thought. Information that is jumbled, not straight forward or leads to other outcomes may lead to the involvement of the brain. For example, the brain has a specific area that deals with pain perception and position in space (primary somatosensory cortex). The brain also has a specific area for dealing with position in space and planned movement (posterior parietal cortex) and motor movement (primary motor cortex). Notice how both the PSC and PPC are involved in position in space (the PSC deals with proprioception and pain may be a function of position in space; the PPC is involved with planned movement so it needs information about position in space as well. Once the movement is initiated, the sensory spinal cord is giving feedback to the PSC, the PPC and to adjacent ganglions in the afferent spinal cord. Any error in this system can create problems. Adjustments are made accordingly.