I think you may be putting too much meaning to excitotoxic damage. Excitotoxins are not good but I have not read anything that suggest they are the cause of PCS.

Some have used anti-convulsants for migraines with varied success. I take one to allow my brain to settle so I can sleep. I don't see how they would treat PCS. But, every brain responds in its own way to meds.

I am concerned that the physical force of some of your head impacts is only a small part of the cause of your struggles. An enhanced startle response can set off a myriad of negative chemistries and symptoms. Various hormone responses may be at play. Stress hormones, excitement/fight or flight hormones, and all the rest would be worth consideration.

The one thing I do know is that the brain has a system for flushing toxins that is very delicate. It does not function well with elevated blood pressure, intracranial pressure, or improper sleep.

I think I already mentioned trying an anti-inflammatory diet.

The first 12 to 24 hours after a concussion should focus on low stress with good sleep at normal times. Basically, give the brain a break. Light stimulation to encourage good brain blood flow.

Since neurofibrillary tangles have been discovered, they have become a big focus for therapies. One monoclonal antibody has already been targeted at them with some success. There will be lots of new developments over the next decade or two.

Have you been treated for PTSD from your assault ? There is reason to believe PTSD and PCS have a link and magnify each other. Even if you don't feel troubled by the assault, the effects of PTSD can still be contributing. A professional's help would be worthwhile.

There are some atypical anti-psychotics that may help. Xyprexa is one. Many are only used for a short period. 30 days of Xyprexa did wonders for me. I am not one to promote meds but in some circumstances, trying them may help.

Are you near an Amen Clinic ? Worth a call.