By: WXYZ-TV - Online
Tuesday, February 14, 2012

ANN ARBOR, Mich. (WXYZ) - Researchers at the University of Michigan have found that a specific hormonal response to intimate stimulation is much smaller in women who avoid close relationships and intimacy.

229 college students--both men and women--ranging from 18 to 37 were studied. Each participant described their close relationship experience.

The focus of the study was to monitor the level of the hormone estradiol, which plays a significant role in parent-infant bonding and romantic relationships among adults.

Researchers took samples of saliva from the participants before and after, showing them one of three random video clips. Each clip depicted a different type of stimulation: intimate, positive, and neutral.

They found the estradiol responses in women who described themselves as emotionally detached to be similar to other women when viewing neutral or positive clips, but when watching an intimate clip, the response in the emotionally distant women was smaller.

The similar responses of all women to the positive and neutral videos suggest that the emotionally distant women may be selective when it comes to observing intimate situations.

Men who described themselves as emotionally detached did not have a response similar to the detached women, but men in the study had lower levels of estradiol to begin with.

The study can be found in the February issue of the journal Hormones and Behavior.

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