This page is no longer being updated and remains online for informational and historical purposes only. The information is accurate as of the last page update.
For questions about page contents, contact the Communications Division.
Research conducted by neuroscience graduate Carey Wilson ’07 and Wendy Hill, Provost and Rappolt Professor in Neuroscience, was prominently featured in the cover story of the February edition of Scientific American Mind.
The article, “Affairs of the Lips: Why We Kiss,” discusses the body’s many physical and neurological reactions to kissing. A portion of the article refers to Wilson’s honors thesis, which focused on the physiological processes associated with kissing. Hill served as Wilson’s adviser on the project.
An excerpt from the article follows:
Kissing unleashes a cocktail of chemicals that govern human stress, motivation, social bonding and sexual stimulation. In a new study, psychologist Wendy L. Hill and her student Carey A. Wilson of Lafayette College compared the levels of two key hormones in 15 college male-female couples before and after they kissed and before and after they talked to each other while holding hands. One hormone, oxytocin, is involved in social bonding, and the other, cortisol, plays a role in stress. Hill and Wilson predicted that kissing would boost levels of oxytocin, which also influences social recognition, male and female orgasm, and childbirth. They expected this effect to be particularly pronounced in the study’s females, who reported higher levels of intimacy in their relationships. They also forecast a dip in cortisol, because kissing is presumably a stress reliever.
But the researchers were surprised to find that oxytocin levels rose only in the males, whereas it decreased in the females, after either kissing or talking while holding hands. They concluded that females must require more than a kiss to feel emotionally connected or sexually excited during physical contact. Females might, for example, need a more romantic atmosphere than the experimental setting provided, the authors speculate. The study, which Hill and Wilson reported in November 2007 at the annual meeting of the Society for Neuroscience, revealed that cortisol levels dropped for both sexes no matter the form of intimacy, a hint that kissing does in fact reduce stress.