Concussions are not solely caused by an impact to the head, they can occur anytime that the head and upper body are shaken violently.
By definition, all concussions affect the way that the brain functions: concentration, memory, judgment, balance and coordination can all be affected. With that said, symptoms can show up immediately, or even hours or days later. I am certain that he had a very thorough neurological work up at OSUMC including a CAT scan. The only way that the doctors would have made the decision to release him is if those tests convinced them he did not have a significant neurological deficiency and that he was not in danger of rising intracranial pressure (bleeding and/or swelling in the brain). However, you can be sure that they will be testing him daily until they are certain he can return to contact.
It looked to me like nausea hit him on the field immediately after the injury and that his balance and coordination were significantly impaired; classic symptoms of a concussion.
I have no doubt that the medical staff will take good care of Braxton and make his health the top priority