Of Primes and Savants Again

A couple weeks back I referenced George Johnson's recounting of an Oliver Sacks' story about autistic twin savants who seemed to have an intuitive or mental sense of prime numbers. The whole subject area is fascinating, even though largely unresolved. I just came across another 1994 study of the subject by psychologist, Hans Welling, HERE. Still no firm conclusions, though he does note, in the end, that some savants may be capable of more 'abstract' thinking than is usually recognized. He also makes note of memory capacities and perceptual (visual or synaesthetic) skills possibly playing a role, but a truly satisfactory explanation of the savant skills seems elusive, and the basic mystery remains: Is there an underlying simplicity to prime numbers that eludes most human rationality, but is accessible to some savants (or does their talent have a simpler explanation)?