I agree that your eyes do work together in conjunction with the rest of your senses. Just like when they 'see' a carrot they would expect it to 'taste' a certain way. In turn they are absolutely not necessary to enhance or detract from any one of them (but certainly always have the potential to, along with your wee brain of course). For audio the best example I can think of is headphones. Good headphones will create an amazingly realistic soundstage, and illusion of 'presence' which would not be affected, other than possible distraction, by your visual sense. I think learned expectations have a lot to do with how our senses process things. With headphones your eyes really have no part in the equation. I'd take that over Newbee's darkened room and NoDoz any day. Certainly the fewer senses that come into play, the more heightened the remaining senses become. Your grey matter has fewer senses to devote it's RAM to processing.
Marco
Marco