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Changes In Body Chemistry In The Face of Fear

Fear Reactions

Years ago while in high school, I was babysitting three very young children as I had done many times before. They were all safely tucked in bed. In an utterly stupid move I discovered the movie, "When a Stranger Calls" on television and decided to watch it. Those of you who have watched the original 1979 version starring Carol Kane and Charles Durning will realize my error immediately. A babysitter, caring for small children repeatedly answers the phone hearing a gruff whisper saying, "Have you checked the children?" From the very first phone call she answers, I got the chills and the hair on the nape of my neck rose in alarm. My auditory perception increased dramatically and I heard foreboding noises not apparent before. I was deathly afraid to check the children in my charge.

Facing Your Fears

Facing Fear

Eventually I forced myself to go check the children even though my brain screamed it was a mistake. My fear was palpable. Sweat trickled down my brow. At any moment I feared a madman would turn the corner and walk quickly down the stairs, bloodied knife in hand! In the movie, the fate of the children was not a good one. Of course, my three charges were found sound asleep unaware of my pounding fear.

Fear Is Rational

What causes our hearts to race and the heightened auditory perceptions, the fear sweat trickling down our brow, the hackles raised? There are biological reasons for these reactions that go back to our early evolution when we were the hunted rather than the hunter. Let's examine the change in our physiology in the face of fear. It is coming closer to that annual celebration of Halloween. What better time to examine why those things that go bump in the night make us feel the way we all do.

Biology of Fear Reactions

Your reaction to fear is a primitive response shared by all animals. It is called your "fight or flight" mechanism which is located in the amygdala located deep in your temporal lobe. After watching a Halloween horror film fest, you need to flee that knife-wielding maniac you fear is lurking around the corner. Your amygdala sends out the red alert, "Danger, danger!"

  1. Blood chemistry is triggered to change so your blood coagulates faster just in case the maniac hits his mark. As well, constricted blood vessels mean less blood loss. Your heart rate skyrockets which is that pounding you hear in your chest as the maniac closes in on his target.
  2. Your hormones change also. Cortisol and adrenalin speed your metabolism - your muscles are stronger and you have more energy. As well, your body creates natural painkillers, so if your increased strength doesn't get you out of reach of the maniac, you won't feel that first blow. If you can deliver a strong kick to his head, you just might get to the door before he catches up with you again.
  3. Fear increases activity in your sympathetic nerves and epinephrine secretions increase from the adrenal gland. Both act on your sweat glands especially the palms of your hands and armpits resulting in a cold sweat which may make it difficult to turn that doorknob and escape the clutches of you know who!
  4. Blood is not only directed to the muscles and heart but also to the central nervous system including the brain. Those heightened auditory perceptions including the soft whisper of shoes on carpet from your approaching serial killer are more easily heard due to the extra blood flow and energy.
  5. Fear also causes the rising of neck hair and goosebumps. This reaction may be a throw back to our fur-bearing ancestors. We've probably all seen cats or dogs react to danger by raising the fur on their back and necks. It makes them look bigger; therefore, more threatening and hopefully their attacker will leave them alone. Both of these responses - goosebumps and rising neck hair - do signal of impending danger but the knife-wielding serial killer probably won't find you any more of a threat. Hopefully your increased muscle strength and energy will take you out of the front door and not up the stairs. You don't want to be that foolish boy or girl that we love to scream at behind fingers over our eyes, "Don't go that way!!!!!"

Check out Part 1 of my Halloween Series

  • Samhain and the History of Halloween
    Halloween is traditionally the night we embrace our dark side. Discover the origin of this ghoulishly fun holiday and the ancient and medieval customs that have resulted in many of the fun and scary symbols of this holiday.


Silver Poet from the computer of a midwestern American writer on October 31, 2011:

Interesting chemistry lesson. The why of what we feel. How we're able to lift a car or throw another human being under extreme duress. :)

Teresa Coppens (author) from Ontario, Canada on October 21, 2011:

I'm hoping that its an appropriate thing to do regarding hubpages. I intended all of the linked articles to part of a Halloween series so it seemed to make sense. Thanks for the story. I think we all liked to get scared once in awhile. Maybe the adrenaline rush gives us somekind of good feeling as an aftershock. Not sure! I know my kids love to get scared on roller coasters. Same idea?

Judy Specht from California on October 17, 2011:

Nice physiology lesson. Now tell me why I would want to have this experience. I watched Psycho when I was in the 9th grade,while waiting for my mom to get home from work one night. She was late.-I really like the way you linked you hubs. I started with one and was drawn to the next.

Teresa Coppens (author) from Ontario, Canada on October 15, 2011:

Scroll to Continue

Thanks for the support princesswithapen. Glad to have another follower. I'll be adding more hubs of a similar nature over the next couple of weeks in honor of Halloween. Hope to hear from you again.

princesswithapen on October 14, 2011:

Wonderful hub, Teresa

The face of fear can weaken the best of us. And sweaty palms, like you've mentioned, are an easy give away. Loved reading this.


Teresa Coppens (author) from Ontario, Canada on October 13, 2011:

Thanks ladies, I had so much fun writing this. My love for science was fun to mix with my love for Halloween. Thanks for reading and commenting!

Rosemary Sadler from Hawkes Bay - NewZealand on October 13, 2011:

Great hub and voted up

As Stephanie says you have a knack of personalizing the science behind the fear. I enjoyed reading this.

It always amazes me in the movies that the victims ALWAYS head upstairs where they are likely to be trapped. I am sure I would be headed for the door but hope I never have to find out.

Stephanie Henkel from USA on October 13, 2011:

Wow! This is a most interesting biology lesson! You have a wonderful way of personalizing the science behind the fear response to make it really good reading as well as easily understandable. Great hub! Voted Up!

Arlene V. Poma on October 13, 2011:

Voted up, useful, interesting, AWESOME and bookmarked. I will think about your hub whenever I hide behind my furniture during a scary horror flick. Fascinating for this time of year!

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