Why Is Central Pain So Relentless?
Charged particles ions flow into nerve cells and cause a voltage spike (as many as 50 times per second). Frequency of spiking determines the strength of the signal. The main ion flowing in with an action potential is sodium. Sodium crosses the cell membrane through crooked tubes known as ion channels. Tiny C fibers carry slow pain and big A-beta or A-delta fibers carry rapid pain. Both groups are subject to inhibitory messages from the brain which can lessen firing and diminish pain. Injured C fibers do not regrow well. So, powerful A-beta/delta fibers grow into the areas where C fibers used to be. These sprouts of new growth do not receive normal input from the brain to inhibit them. Central pain causes a disastrous increase in ion channels. These are called Nav 1.3 normally found only in the fetus. They render nerves so sensitive that they cannot quit firing. The brain cannot contact these cells to tell them to shut off. The cells become pain puppets, not responding to injury, but co
