Regarding the flying, Aircraft cabins never get to a pressure altitude above 8000 feet. The plane may be flying at 35,000 feet but the cabin remains pressurized to 8,000 feet. Some even pressurize to 7,000 feet for better passenger comfort. The extended duration at 8,000 feet can cause cognitive symptoms temporarily. If there are other issues, it would likely be from ear congestion.

I would not spend the money of MRI, fMRI or such. There is not much that can be done, even if they can see a problem.

Have you tried talking to your adviser about your struggles? It is worth a try.

Regarding resting, you may be able to reduce your other activities that do not directly impact your grades. Forcing your way along with concussion symptoms is like driving a car in the mountains without brakes and hoping you do not come to a downhill grade. The stress load will eventually impact you much worse than it currently is.

You need to have some good discussions with your parents and faculty advisers.

Print out the TBI Survival Guide in the first sticky thread. It should paste into MS Word OK. It has some great advice about returning to school. Your parents and faculty advisers need to read it, too.

My best to you.