How can nerves be less precise and more sensitive at the same time?

I know it seems paradoxical. See if this helps:

Remember a time when you walked from a very brightly lit room into a dark one and  you couldn’t see a thing. You gingerly put your foot down to make sure you didn’t miss a step and you moved very carefully until your eyes adapted.


In that instance, because you couldn’t see well, your nervous system went on high alert and became more wary, causing you to pay really close attention as you made your way across the room. Your “threat meter” was in the red zone on high alert. The same thing happens when the nerves in your back, arms, or legs are smudged by persistent pain. Your nerves have effectively left you “in the dark”, so your brain pays really close attention to any potential danger signs. You have turned up the danger sensors and the brain, which determines whether or not you feel pain, is making sure you get the message.

Smudging happens over time. The longer pain persists, the more likely it is that the sensors are not giving you accurate information from your body. It’s all happening behind the scenes, so you’re probably not even aware of it. But if you retrain the nerves in your body to give you more accurate information, it’s like turning the lights on in that dark room. You can move again with less trepidation and everything relaxes.

How to turn the lights on….

Can you tell if I’m touching you with one finger or two? It’s the question we ask when testing for two-point discrimination. We measure exactly how far apart the points are before you can feel the two points as separate. Nerves in an area where you’ve had pain often lose precision. For example, in the back, normally you can tell that you are being touched at two separate points when the points are 40 mm apart. Closer than that and it feels like one point. Persistent pain often makes it much harder to tell if you are being touched with one or two points. We have norms for each body area, and we test your accuracy in two-point discrimination and compare it against the norms. If there’s a problem, we will help you retrain those nerves and relax the nervous system-metaphorically turning the lights back on.

The body and the brain both change with persistent pain and in PT, we address both. Pain Education is a key part of the pain solution. Just understanding what’s happened increases endorphins to the brain, and you feel better. Then, we work on more body-centered therapy, like two point discrimination, to help you get better.

If you have persistent pain, make an appointment to see us. We have new tools to use, in addition to many that are tried and true, to help you recover and get back to doing what you love.

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