quote:

At Pennsylvania's Lafayette College, Hill, the neurology professor, is studying the chemicals that the body releases—and exchanges—when couples kiss, such as the stress-related hormone cortisol and the bonding-related chemical oxytocin.

"We think [kissing] has stress-reducing properties at least for those couples who are in committed relationships," said Evan Lebovitz, a senior neuroscience major who is Hill's assistant.

How did they determine this?

Hill and her team split a group of college-age couples into two groups: Members of one kissed for 15 minutes, and the others conversed without physical contact. She took blood and saliva samples before and after the sessions.

While getting college-age couples to kiss doesn't sound like a tough task, Hill didn't take any chances and turned part of the school's neuroscience building into a love den; the team lit candles, hung drapes and soothed the students by playing smooth jazz.