How It Works

20 SPOOKY

WHY DO WE GET GOOSEBUMPS WHEN WE’RE SCARED?

Sitting at home, alone and in the dark, a sudden sense of fear and a swift chill may wash over your body. Sure enough, your hairs stand to attention and goosebumps cover your skin. It’s a sensation we’ve all felt at one time or another, but why does our body react in this way when we’re scared? It harkens back to a time when ancient humans faced the daily fear of life-threatening predators. As a result our bodies evolved what we now call a fight-or-flight response. This is a stress response which triggers a release of adrenaline, causing our heart race to rush, our palms to sweat and goosebumps to appear. During this state of fight or flight, the tiny muscles adjacent to each hair contract, making hairs stand on end. Today humans are relatively hairless compared to our animal ancestors. Charles Darwin postulated that at one point in time our ancestors would have been a great deal hairier, and goosebumps would have puffed out their hair to make them look bigger and appear more intimidating to potential predators.

Dissecting goosebumps

How our hairs stand on end when we’re scared

Goosebump

During the contraction of arrector pili muscles, the skin on the surface puckers like a plucked chicken, forming a goosebump.

Hair

There are about 5 million hair follicles across the entire human body, each equipped with muscles called arrector pili muscles.

Contraction

A release of adrenaline in the body causes these muscles to contract, in turn pulling the base of the follicles and making hairs stand on end.

Relaxed

These tiny muscles attached to the base of the hair follicle are normally relaxed, allowing the hair to naturally lay on the skin.

IS MIND-READING POSSIBLE?

Our thoughts are our most private and personal belongings, and the idea that someone could go snooping around inside our heads is terrifying. However, the technology to do

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