The article on Chessbase begins: "In a recent research project on expert chess players, scientists found that male chess players choose more aggressive chess openings on average when playing against good-looking female opponents compared to when playing against less attractive female opponents, although they are equally skilled, experienced and of similar age." (http://www.chessbase.com/newsdetail.asp?newsid=7569)
I can only recall playing a couple of members of the opposite sex, and fortunately, both were too young for me to have lascivious thoughts. There is no way for me to know from experience if I would be more agressive if I crossed mental swords with a pretty woman.
One does have to face women in backgammon though. I always found it disconcerting to play any woman, whether attractive or not. I recall facing a woman in the very first round of a major tournament; that being a weekend tournament, as opposed to a nightly tournament. With only one checker left I was off the next roll. My opponent had four men left on her six point which meant only one roll-double sixes, a 35-1 shot-would win for her. When the dice landed on double sixes, I thought of something a friend used to say. "Supposed to happen."
"Oh Michael, I'm so sorry," she said. "You're a top player and have a chance to win this tournament." I looked at this woman and thought before speaking. She was nice enough when she was not drunk. She came to many tournaments for the social aspect of it and never won, but kept coming back. Players like her enhanced to prize fund considerably. She would keep coming back, telling anyone who would listen that she once beat me in an official tournament match. I smiled and said, "Do not ever say you're sorry to win! You play all the time and are bound to win sometime. It is my misfortune that it happened to be at this time. Good luck in the tournament." She was knocked-out in the next round.
The Legendary Georgia Ironman played the lovely Jennifer Shahade once. He had this to say about the experience, "I went 69 tuff moves facing down that double-barreled shotgun!" I have often wondered whether Tim was more, or less, agressive playing that game.