Men are moved by the physical and are always ready to have sex while women need a little more than cajoling to get her in between the sheet.

According to Cindy M. Meston, Ph.D. and David M. Buss, Ph.D., psychology professors at the University of Texas at Austin and coauthors of Why Women Have Sex: Understanding Sexual Motivations from Adventure to Revenge (and Everything in Between), it might be time to learn what really gets her psyched for sex and for a better understanding of how to get her in the mood.

Guys, here are the following eight factors that Meston and Buss say affects a woman’s desire for sex: