Hair Raising


electric razors just don’t give you that clean shave

That’s right brothers and sisters Halloween is one of my favorite Hallmark holidays. The candy, ghost stories, bad zombie makeup, and shapely women in revealing witch costumes all put me in the holiday spirit. I have to admit though, something has been bugging me. There I was, watching cheesy, poorly scripted thriller movies at 1am alone in my creepy old apartment. I’m watching one of those scenes where the woman in a low cut top is searching the basement with a flashlight for strange sounds when I feel the hairs raise on the back of my neck. “Why is that?” I think to myself. No, I know why MY hairs stood up. I’m a total wuss when it comes to ghost thrillers, but why does that physiological response happen to all of us when we get spooked?

scared cat

cat demonstrating pilomotor response to confrontation while walking the mean streets

Ancient roots

There is something you and your cat have in common that you may not know. Scientist refer to it as the pilomotor response. You may know it better as “goosebumps” when hundreds of tiny bumps raise on your arms and legs. If you’ve ever gotten out of the shower and stepped into the much cooler air outside of your bathroom that’s typically when you’ll notice them. Well cats display this same behavior when they are confronted by another aggressive cat telling him to “step off my turf” or something scarier like a dog or falling metal trash can. The hairs extend as they rise to their toes to appear as big as possible for competition or predators. Well the cool kids (scientists) believe that this phenomenon in human beings served a similar function. Well I don’t know if you’ve noticed, but humans beings today, version 5.0, aren’t nearly as hairy as our fiercer, planet of the apes ancestors.

goosebumpWell these days goose bumps are a “vestigial” response meaning it has out lived it’s original function. However, this involuntary reaction is still triggered by moments of intense stress and emotion like fear, exhilaration, and you know, moments of (sexual arousal). All of this magic is of course brought to you by our dear friend the sympathetic nervous system, home of the “fight or flight” response.

Let me set the scene… 

Let’s say you just walked out of the shower…No wait better yet, let’s say Michelle Rodriguez just walked out of the shower wearing nothing but a towel when suddenly she hears a loud crash from the kitchen…

About 90% of the heat in Michelle’s super fit body is lost first through the skin, even more so when wet, because water transmits heat away far more efficiently than air.

She slowly walks down the stairs….

Respiration increases along with her heart rate as blood flow is conserved for the brain and other vital organs, temporarily halting digestion. A sudden rush of energy is felt as epinephrine acts on the insulin producing liver cells, allocating glucose so that Michelle’s warrior, Resident Evil reflexes can spring into action if need be.

She approaches the doorway of the kitchen, reaching for her limited edition, zombie killing, 9mm Smith & Wesson…

The adrenaline coursing through her blood stream has taken her mind off the chill in the air but her body is still losing heat through evaporative cooling of the skin and through the rapid breaths (lungs accounting for 10% of total heat loss).

She turns the corner..

Tiny, arrector pili muscles located at the base of the hairs  on her neck, arms, and perfectly toned legs contract forming goose bumps and raising the hairs on Michelle – as both a response to fear and her body’s attempt to conserve heat.

She puts the safety back on her pistol, realizing that it was just her silly cat knocking over a bowl of Captain Crunch. That’s when it dawns on her “I only buy Raisin Bran!”

Happy Halloween my friends and as always…stay curious, stay classy, and never stop learning 🙂


“André tells the best stories”

3 thoughts on “Hair Raising

  1. I enjoyed reading this one! The ANS is truly an amazing concept, but also a difficult one to understand. We tend to take the autonomic nervous system (ANS) for granted. Surely we talk more about the wonders of the brain for cognition than we do the hidden subsystem (ANS) that connects us with our environment!

    Michelle Rodriguez is indeed a classy and talented actress!

    • Thanks for visiting my site Kenel! I’m glad to hear you liked this article and it’s reassuring to know that I didn’t completely butcher this topic. Anytime an article takes me in the direction of the CNS or ANS it feels like Inception and I’m just navigating through a dream within a dream to resurface with an explanation of where I’ve been 🙂

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s