"The experiments also revealed a rather surprising effect: both men and women found it easier to have an orgasm when they kept their socks on. Draughts in the scanning room left couples complaining of "literally cold feet", and providing a pair of socks allowed 80 per cent rather than 50 per cent to reach a climax while their brains were scanned."

http://www.timesonline.co.uk/article/0,,589-1662280,00.html