I've not had to deal with concussions, but 10 yrs of depression and finally a good ole time doc I talked to realized ikt was a low funcioning thyroid and put me on desiccated support and the depression was gone in 4 days. This is my story and just sharing. Thyroid is so overlooked.....Drugs are handed out like candy. Zoloft was one of them in my 10 yrs of depression.