I believe that Giles Brindley (https://en.wikipedia.org/wiki/Giles_Brindley) famously did exactly this - sitting in a bath of ice water to lower his body temperature in an attempt to reduce the dark noise in his retina. I can't find a copy of the paper unfortunately... EDIT: Some details about this and his more colorful work on erectile dysunction here: http://web.archive.org/web/20150204122651/http://alignmap.co...