This is Jake.
He has a particularly cheesy grin because he’s appearing on BrainCraft and his shirt
is covered in, well, cheese.
If you find yourself smiling too, it’s not his charm.
We mimic each other’s facial expressions, posture and elements of speech all the time;
mostly without actually realising it.
Back in 1992, researchers looked at the activity of single neurons in the brain of the macaque
monkey.
They came across a system of neurons that fired both when the monkey performed an action
- grabbing a peanut - and when the monkey observed a researcher grabbing a peanut too.
The researchers called the system “mirror neurons” because the neurons “reflected"
a behaviour; even though the monkeys weren’t performing that behaviour themselves.
And “mirror neurons” aren’t just a monkey thing, there’s evidence for the system in
human brains too.
In one study, human participants were shown a face with either a happy, angry or neutral
expression...
but only for 30 milliseconds.
The expressive faces weren’t on the screen long enough for the participants to notice,
so they had no idea that they were being subconsciously exposed to them.
Still, the participants who were shown the happy face had increased electrical activity
in the muscles needed to smile, and mimic that face.
And those shown the angry face initiated the muscles needed to mimic the angry expression.
It’s thought that we mirror behaviours and facial expressions to help us understand the
emotional states of others and learn by imitation.
In another study, researchers impaired the participants ability to mimic faces by having
them chew gum, or hold a pencil in between their teeth.
Their ability to recognize some emotional expressions, like happiness, was impaired
too.
So this mirror neuron system isn’t only connected to our movements, it may also be
connected to our feelings.
In a recent study, participants were shown videos of a hand in either visibly cold or
visibly warm water.
While watching the cold water video, the participants’ hands dropped in temperature.
Researchers dubbed this “temperature contagion.”
The drop in temperature was more noticeable in participants who reported having higher
levels of empathy, but we can't say if this was caused by mirror neurons or not.
Some neuroscientists are skeptical of the mirror neuron theory and say it’s been over
generalised.
While research into our neurons role in imitation is ongoing, we do know that we’re primed
to mimic what we observe - from cracking a smile to the point where we can “catch a
cold” without actually experiencing a change in temperature.
It really is a case of monkey see, monkey do.
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