I had a bit of a change 6.5 months post injury...One huge change was that I rarely had the massive belt tightening electrical shock around my head with cognitive effort. I still have symptoms and feel awful a lot of the time, still unable to work full steam, but I did feel a change at that time.
Re neuropsych....not sure if I would pay for it. My LTD plan wanted it, so I did it. he was able to tell me my main problems were with visual memory, but was not able to tell me things I know are affected....concentration, emotional things, stress management, apathy feelings from time to time, etc. It depends why you want it, I suppose. I would spend my money on visual testing (neuro), physio, ice packs

, etc.
Hang in there. It gets better!!!!!!