Researchers have only recently discovered an olfactory nerve that they believe is the route through which pheromones are processed. Nerve “O,” as it is called, slipped under the radar for many years because it is so tiny. However, when the nerve was discovered in a whale, scientists surmised that this little nerve might be found in humans as well. And it was!
So what is the role of Nerve “O”? Nerve “O” has endings in the nasal cavity, but the fibers go directly to the sexual regions of the brain. Indeed, these endings entirely bypass the olfactory cortex! Hence we know the role of Nerve “O” is not to consciously smell, but to identify sexual cues from our potential partners... (MSNBC)
Interesting discovery. Given previous research that the hypothalamuses ("a part of the brain that governs sexual arousal") of gay males responds the same way as heterosexual females to male pheromones, I'm curious whether this find is related in some way. It would be interesting to expand research on this to explore the possibility.