Nobody knows exactly when human beings started kissing each other. It’s a bizarre behavior that’s not replicated anywhere else in the animal kingdom. But kissing – if you’re doing it right – can actually be a scientifically-proven pathway to further intimacy. Kissing the central ridge of the upper lip, just below the philtrum, sends a signal to the somatosensory cortex in the brain to produce pleasure hormone oxytocin. That hormone is deeply intertwined with forming emotional bonds with people. The tip of the tongue is also a trigger point for oxytocin release, so work on your French kissing as well.
Photo credit: Flickr user andraspfaff via Creative Commons