What are things you've taken? I don't think it's placebo at all or at least from studies I have read(there are mostly using healthy patient). I am currently learning neuropharmacology because of it. Though it is not my major but it has been something I studied for about two years now. I also left a comment on your dad's post about my condition.

So far & daily, I have been taking piracetam but previously, I took pennywort. Now I am experimenting with ginkgo biloba but piracetam does the job better than other stuff. As the moment I am writing this, I was off on piracetam and currently on again, self-studying and experimenting with piracetam by taking 1600mg dose/day. I also think some combination of vitamins B did the job.

I have had couple incident with concussion but it has been 3 and half years for my major brain injury and during those three years, I got several more accidents and bang my head couple of times. I don't have problem with cognitive functioning but I have problem with executive functioning (controlling impulses & emotion and also attention), almost ADHD like. I suffered from memory loss, there are many memories growing up that I didn't remember. I woke up from the accident speaking different language and losing my inability to speak what is supposedly my mother tongue. There are many new personalities that I picked up too.

I do wonder, does he have trouble with speech? trouble with naming things? more pauses? easily fatigued?