See also how brain connectivity gets changed by psilocybin (magic mushrooms): http://mindblog.dericbownds.net/2014/12/psilocybin-changes-brain-connectivity.html

See also how brain connectivity gets changed by psilocybin (magic mushrooms): http://mindblog.dericbownds.net/2014/12/psilocybin-changes-brain-connectivity.html http://mindblog.dericbownds.net/2014/12/psilocybin-changes-b... (and the actual paper: http://rsif.royalsocietypublishing.org/content/11/101/20140873 http://rsif.royalsocietypublishing.org/content/11/101/201408...). In short: you get more long-range correlations, so the perceived synesthesia may have very "hardware" basis.