Whether you're cold, scared or listening to some great music, you've likely
experienced goosebumps at some point in your life. But have you ever wondered why
this strange change takes over your body? Named after the way poultry looks
when plucked, goosebumps are a fairly useless trait in humans which have been passed
on by our ancestors. Each hair actually has a tiny muscle attached to it called
the erector-pili muscles and when these muscles contract the hair stands up on
end. This contraction creates a shallow depression around the hair causing the
surrounding area to protrude. And it's the stress hormone adrenaline which
triggers this physiological change to occur. So what triggers adrenaline? For
one being cold, in animals with much more hair on their body this response helps
them to stay warm. The standing hair is able to trap more air and thermal
regulate it ultimately providing an insulated barrier. Apart from this
adrenaline is also triggered under stressful situations leading to the
"fight or flight" response, like when you're scared. Cats are a perfect example,
if you give them a spook their hair shoots up on end.
This involuntary evolutionary response allows animals to appear bigger and
more intimidating. But why music has the ability to cause chills or "frisson" as
it's called is not fully understood. One interesting theory suggests that
elements of music such as sudden volume changes or unexpected unique sections
induce a sub-conscious fear response. The body loves predictability and so
anything surprising to the autonomic system stimulates an alarm. But this fear
quickly subsides as our brain realizes, "hey, it's just music". And this contrast in
experience causes the frisson and your goosebumps. There are other
theories as well, ultimately the brain is extremely complex and so a relationship
between music, emotion and physiological responses is difficult to decipher but
in science it's okay to say that we don't know...yet.
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