Smilin was right about the brain's struggle to regulate blood flow and blood pressure for many with PCS. You should buy a blood pressure kit and check you blood pressure during head aches and other strange head sensations. You will likely find some connections.

I am surprised that you have not been advised to stay of the track, at least until all of you symptoms are gone for a month or two. I suggest you consider leaving the track all together. It appears that you brain either is or has become very sensitive to stresses. The vertical and horizontal G forces transmitted to your head during riding and hard turns is likely too much for your brain, at least for the present time.

I am curious about your Neuro-Psych Assessment. Was it a full day of testing or an abbreviated test of an hour or two? The psych's interpretation sounds common. When they test someone with a higher intelligence than the normal for their age, the psych tends to discount many other indicators of brain dysfunction. Knowing more about the individual scores/ percentile rankings could help shed some light on what is happening with your brain.

Otherwise, you need to spend some extended time in a low stress environment to let your brain continue healing. What kind of work do you do?

Day to day work stresses can hamper your brain's ability to heal.

My best to you.