The concept of kissing is weird. You are rubbing your open mouth on another person’s open mouth. It’s kind of gross, so why do many people find it so wonderful?
As you start to kiss, you engage five of your 12 cranial nerves and more than a dozen facial muscles. One of those muscles allows you to make a puckering shape with your lips. This is the same shape needed for breast feeding. Kissing may trigger pleasure because it is closely related to breast feeding. Breast feeding is a very neurologically pleasurable experience. It releases the hormone oxytocin, which promotes bonding and comfort in mother and child. Kissing is also a nasal experience. Breath can be an indicator of health in a potential mate. We actually might be able to smell a genetic match. Finally, the sensation of kissing sends signals directly to the brain’s pleasure reward centers and releases a spectrum of hormones and neurotransmitters, like dopamine and endorphins.