Don't misunderstand me.  He had a neurological problem for sure.  What I am wondering after listening to his symptoms is if he actually had a concussion or something else.  Let me explain.

Several years ago, a friend of mine was having problems with her shoulder due to a repetitive strain injury.  After getting a lot of regular doctor run around, she settled on going to someone who did deep tissue massage to get relief from her swelling and muscle weakness in her right arm.  At first, it went really well.  The strength came back and the swelling was just about gone.  Then rather suddenly it all came back and with a vengeance.   New symptoms appeared which sounded eerily reminiscent of Crosby's.  Trouble with motion while riding in a car.  Extreme sensitivity to noise and light.  It was all vey strange and bizarre.

She stopped the therapy and went to a trigger point person who was more specific about the treatment and did not do the deep tissue massage.  The symptoms faded and she is pretty much near normal now.  The working theory is that the massage therapist worked heavily on her neck and bruised it to the point that swelling was starting to affect the the top of the spinal cord or the base of the brain.  Nobody hit her with a baseball bat or dumped her down the steps or any other trauma like that.  

I don't know... I don't have the specific information or nor do I pretend to.  However, when I heard the Crosby talking about his symptoms, it was kind of eerie.  

Just wondering...