Answer transcribed from Brightway's interview with physical therapist Susan Little:

This is a common complaint after a traumatic brain injury. Although I don't have the full answer, and I would encourage you to talk with your neurologist or your primary care physician to see if there are things that can be addressed from a medication point of view, I can talk about the basics. Considering the mechanics of hitting your head hard enough to suffer an injury to your brain, there's a lot of things covering your brain. Whether it's the nerve endings on your scalp or under your scalp, there are a lot of things there that can be damaged and can become sensitive as nerves are damaged. They do often become hypersensitive. I'll take that over being numb because at least hypersensitivity means that they're growing back and they're trying to recover, but it's a bumpy recovery when you can't wear your baseball cap. 

Most of this research is actually done with amputees. For an individual who has lost their leg, you can imagine the nerves that went to their foot or the portion of their leg that has been amputated have been damaged and have been cut. They become hypersensitive because the ends of those nerves are still there. We find good success in providing sensory stimulus to those nerves, so those nerves learn that they can chill out and accommodate that sensation. So with an amputee, I'll tell them to start by just rubbing their leg with their hand and then move to rub their leg with a washcloth that is a little bit coarser. Or, maybe just tapping their leg and providing just a gradual progression of sensory input until those nerves become less sensitive. We refer to it as accommodation. You do it every single morning when you first put your socks on. You feel your socks and unless I say to you “hey are your socks comfortable” you haven't really thought about them all day long. Those socks are on your feet but your body accommodates the sensation of having those socks on so much that maybe you think “do I have socks on? Let me check”.

We can do the same thing hopefully with those sensitive nerve endings in our heads. Maybe it's just doing a gentle scalp massage to begin with. Maybe a little bit more aggressive or maybe again, rubbing with a washcloth or doing some tapping to decrease that sensitivity. Generally, as human beings, if something hurts we don't do it. However, in this instance, you might want to try doing just the thing that is irritating to see if you can decrease the sensitivity. Now, if it sets off horrible other symptoms like a headache or a migraine, maybe you're not ready for that. Again, I'd encourage you to talk it over with your physician because there may be medications or other approaches that could help to decrease the sensitivity of those nerves. Also, if you still have open areas, staples, or stitches in your head, you don't want to be going there. However, if things are healed and you have that sensitivity, you can start that gentle reintroduction of tactile and sensory stimulation to that area.