With the book `` Fifty Shades of Grey '' still flying off the shelves , women are discovering the power of sexual fantasy , some for the first time . According to neuroscientists Ogi Ogas and Sai Gaddam , authors of `` A Billion Wicked Thoughts , '' while men tend to have visually driven fantasies , women prefer to fantasize about what a man might do to them . For example , the top five female fantasies involve having sex with a stranger , being worshipped in bed , being ravaged in bed , being watched by others and enjoying a threesome . In other words , women tend to fantasize about being the object of desire . Erotica is wonderful , but you do n't need a book to feel sexy . In fact , indulging in a little bit of fantasy on your own may be even more effective at spurring both sexual desire and arousal , according to a recent study . 4 ways to rev up your post-baby sex life . Researchers at the University of Michigan have shown that different forms of sexual fantasy may have a real impact on arousal and desire , particularly for women . For their study , published in the Journal of Sexual Medicine , Katherine Goldey and Sari van Anders randomly assigned 128 women and 98 men to one of four groups , or `` arousal conditions . '' One group completed an imagined social situation exercise in which they imagined a positive sexual encounter and then answered open-ended questions about it . The others engaged in typical unstructured fantasy ( imagining sexual situations but not writing about them ) , while others read an erotic story of the researchers ' choice or took part in a neutral exercise ( writing about the room they were in ) . Then they rated their perceived genital arousal ( how they felt physically ) , as well as their `` state '' desire ( whether they wanted to have sex ) . The results : The first three groups all reported experiencing increased genital and psychological arousal , as well as higher `` state '' desire , compared with the neutral group . The group who engaged in unstructured fantasy had the greatest arousal . Interestingly , though , the researchers also measured `` trait '' desire -- sort of a person 's general set point for sexual desire , once believed to be unchangeable -- and discovered that the imagined social situation exercise group , the ones imagining a positive sexual situation , reported significantly higher trait desire after that exercise . Sex or money : What makes you happier ? That 's great news for all of us , but particularly for women , who often tend to experience sexual desire in response to the sex they 're already having . In other words , you may not feel quite so `` into '' sex in the beginning , but your desire and arousal grow as the interlude progresses . Indeed , female sexual response is typically characterized by `` responsive desire , '' while male sexual response is more likely characterized by `` spontaneous desire , '' says sex educator Emily Nagoski , author of the `` Good in Bed Guide to Female Orgasms . '' `` 'Responsive desire ' is when motivation to have sex begins after sexual behavior has started : You 're doing something else when your partner comes over and starts kissing you , and you think , 'Oh yeah ! That 's a good idea , ' '' she explains . `` 'Spontaneous '' desire , more typical of male sexuality , works more like this : You 're walking down the street and for no immediately obvious reason you think , `` Hm . I 'd like to have sex ! '' As the new study suggests , actively fantasizing about sex is n't just a way to pass the time . It can create real changes in your body , moving you from thinking about sex in the abstract to fueling real desire and arousal . Fantasy is also a sign of a healthy sex life , and sharing those fantasies with your partner does n't just have the potential to spice things up in the bedroom . It also means that you feel secure and confident in your relationship . It 's often been said that the brain is our biggest sex organ , and this study only confirms that . So , give your brain a workout with a fantasy or two . You might be surprised where it leads you . Beyond 'Fifty Shades ' : Sex experts share their favorite books .
Women tend to fantasize about being the object of desire while in bed . `` Fifty Shades of Grey '' may have helped women discover the power of fantasy . Fantasizing can spur both sexual desire and arousal , research shows . Sharing fantasies with your partner means you feel confident in your relationship .