Pheromones are not scents. They are completely odorless. But any time you’re near another human being, you’re being exposed to them . . .

One of the big “what if” questions that got me started on my current novel-in-progress, Dark Chemistry, was this:

What if a bad guy figured out how to manipulate a woman using pheromones?

So as I started working on the novel, I did a bunch of research on pheromones.

It’s a fascinating topic.

For example, did you know that there’s a structure in the nose of mammals, called the Vomeronasal Organ (VNO), the purpose of which is to detect pheromones?

If you were to examine the human VNO with a microscope, writes Michelle Kodis in the book Love Scents, you would find that it is connect to a “tube lined with columnar cells.”

These cells are classified as pseudostratified columnar epithelium, and what’s intriguing about them is that they are not found anywhere else in the human body–they are unique to the VNO.

Caveat. Some scientists are less than impressed by the VNO and VNO lining. They believe that in humans, the VNO is vestigial.

But hey. Until a few years ago, scientists thought the appendix had no purpose, either.

And there’s no question that we humans respond to pheromones. Pheromones probably explain why, when women live together, their menstrual cycles synchronize. They’re probably one reason blindfolded mothers can identify their babies. They probably explain why we –instantly — find some people physically attractive, but not others.

Pheromones have the potential to influence everything from your heart rate to your mood — but their effect is entirely below the threshold of conscious awareness. (Image credit: http://www.sxc.hu/profile/Tallia22)

Something else that’s fascinating to me: our reaction to pheromones happens below the threshold of conscious awareness.

Pheromones, you see, act directly on the autonomous nervous system: the chemical signalling system pheromones activate delivers impulses directly to the hypothalamus — the portion of the brain that controls body temperature, hunger, thirst, sex drive, our moods — and the pituitary gland, called the “master gland” because it controls most of the body’s other endocrine glands, from the thyroid and adrenals to the testis and ovaries.

So think about it: when we’re near other humans, we’re reacting to chemical signals — and we don’t know that we’re reacting to them.

Kinda spooky, isn’t it?

But stay tuned . . . it gets spookier . . .

;-)