I can understand your worry over setting yourself back, but from what I've read & from what Mark in Idaho has posted, I don't think the little jolts from your car will count as subconcussive impacts. The pillows are a great idea to try. Just out of curiosity, would it be possible for a friend or someone in your family to drive you to work? You might be able to relax a bit, recline the seat, etc. and see if that helps.