Weird, I was just thinking about the difference between "muscle memory" (procedural), and declarative memory. Except I was thinking about people on the opposite end of the spectrum: Hyperthymesia. I was wondering if those with the condition also have superior procedural memory, but if the two forms of memory don't share the same neurological underpinnings, hyperthymesiacs shouldn't have perfect procedural memory, correct?

edit: and as a corollary, I wonder if there is a condition for procedural memory parallel to hyperthymesia for declarative memory. It seems very possible, since hyperthymesia wasn't even recorded until 2006, and a superior procedural memory would be less salient.