I found it to be an older but interesting article for those of us who are not named Lane. (no offence intended Lane, you are sometimes just too far beyond my level of understanding to be useful for me) 

 You may have to copy and paste, or google search it, unless someone wants to convert it in a subsequent post to something that will link, I've tried and cannot manage it.

 https//symbiosisonlinepublishing.com/neurology/neurology12.php