Of Numbers and Colors...

A recent medical study looks at synesthesia (the cognitive blending of sensory information) and numbers, and the differences in cortical activity between "synesthetes" and others:

http://www.medicalnewstoday.com/releases/237908.php

Well-known autistic savant Daniel Tammet is famous for his synesthetic experience. He expounds upon what it all means in this TEDTalk from earlier this year:



Tammet is also famous for his depiction of how he visualizes the number pi in color (a number he has recited from memory to over 22,500 digits -- no, that's NOT a misprint):

 

see here: http://www.newscientist.com/gallery/mg20227111500-savant-art