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If you read some of the less-reputable corners of the internet,
you might have heard strange things about mirror neurons.
According to some people, they are why we have empathy.
And ESP.
And telepathy.
It probably goes without saying that most of that isn’t true.
They definitely don’t give us superpowers.
And there is conflicting research about whether they’re the basis of empathy.
Even if they’re not, though, they are still a very cool part of your brain
and probably, they help us learn from other people.
The name mirror neuron comes from the fact that they fire
both when you do something and when you watch someone doing something,
even if you don’t move a muscle.
Basically, it’s as if they mirror the neural activity of the person actually doing the thing.
And they were first discovered in macaque monkeys in the early 90s .
The story goes that one day, while a monkey had thin needle electrodes
inserted into individual neurons in their brain, some of the graduate students...
well, they went and took a lunch break.
And while one of those graduate students was eating in front of the monkey,
all of a sudden there was neural activity in the premotor region
of the frontal cortex in the monkey's brain.
This region would normally fire if the monkey was moving—
like reaching for food or eating.
But those neurons were firing while the monkey was motionless
and just watching someone else do those things.
Further research started mapping out exactly where these neurons were—
and they're remarkably specific.
Like, mirror neurons that fire when an experimenter grabs a piece of food
wouldn't fire if the experimenter used tools to grab the food instead.
But the big question was whether this happened in humans, too,
because these neurons were in regions of the brain where
monkeys and humans differ quite a lot.
Of course, your average human study participant is a little fussier
about getting electrodes planted into individual neurons inside of their brains,
so scientists used electro-encephalograms, or EEGs,
to look for mirror neurons instead, as they record neural activity through the scalp.
Researchers had 20 subjects watch an experimenter demonstrate some
motions with their thumb and index finger and perform the same motions themselves.
And turns out some regions of their brains did act like the monkeys' mirror neurons —
parts of the motor and premotor areas of the frontal lobe, for example,
as well as where the parietal lobe meets the temporal lobe—
an area involved in vision and focusing attention.
But knowing that they’re there and where they are doesn’t tell us why they’re there.
Many neuroscientists now think they help us learn from other people through observation.
Take a 2009 study, for example, which looked at how these parts
of the brain are active while people were being taught how to dance.
The researchers used a game similar to Dance Dance Revolution,
and varied whether the participants were taught the steps using
symbols on a screen or a human model in addition to the symbols.
And they found that parts of the mirror neuron network really tune in to human actions.
For example, the superior temporal cortex was more active while
watching a person demonstrate the dance than the symbolic break down of the steps.
But perhaps more to the point, the participants’ performance on a final
dancing test was better when they had a human to watch,
which suggests that these regions support observational learning.
Human mirror neurons aren’t exactly the same as the monkey ones, though.
Ours seem to care about the actual movement,
while theirs are more strongly tied to the movement’s meaning.
Like, say you grab a water bottle the way you normally would.
And then, you put it down, and grab it with your hand upside down instead,
which makes drinking it a lot harder.
It's basically the same muscle motion either way, but one serves a meaningful function.
In a macaque, watching the meaningless action might not activate their mirror neurons.
But in people, the mirror neuron regions of the frontal lobe activate regardless
of whether the action makes sense.
All that matters is the actual hand motion.
It’s possible that this helps explain why humans are so good at learning by imitation—
part of our brain is always paying attention to motions that seem meaningless,
just in case we can learn from them.
Now, you might be wondering where empathy comes in to all of this.
Well, when you think about it, if part of your brain activates
the same way when you're observing an action as when you’re performing it,
then it isn’t that far of a stretch to think that these mirror neurons could be involved
in feeling part of what someone else is feeling simply by seeing them express an emotion.
And although this would be very cool if it were true,
the research to date is kind of all over the place.
Like, one study did find that mirror neurons activate
when people empathize with characters in scenes.
In one scene, for example, the 18 subjects had to identify
the emotions felt by both a son who was bringing home a failing report card,
and a dad who hasn't yet seen it, for example.
And in addition to identifying the emotions of both characters in the story,
they had to guess what both characters would be experiencing if they had more information.
One of the mirror neuron regions — the inferior parietal lobe —
was active while identifying the emotions in the story.
And scores on a test of empathy were related to how active that region got
when they had to make an inference about the dad, who was still in the dark.
Not all studies show this, though.
In fact, many do not.
But, then again, most studies in this area have small sample sizes,
so there's a chance that there are real relationships between
these neurons and empathy that aren’t being detected.
And just to make things more complicated, these studies are all correlational.
They can say that there’s a relationship, but they can’t directly infer causality.
Which means, in the end, we don't know if these brain regions are necessary
for empathy, or if they just happen to light up when we’re experiencing it
for some unrelated reason.
Like with so many things, especially in brain science,
we need more research to figure out what role,
if any, mirror neurons actually play in empathy,
or if they’re a part of why humans are an unusually social species.
They do, however, seem to be a big part of how we learn skills through observing others.
And that means they’re probably an important part of how we share skills
and behaviors and pass knowledge down from generation to generation.
So no matter what, they are a big deal.
They likely are playing a huge role in culture
and in all those things that just make us human.
Thanks for watching this episode of SciShow Psych!
And a special thank you to all of the people who support us on Patreon,
because we really couldn’t make this show if it weren’t for you.
If you’d like to learn more about how you can be one of those
excellent people who support this, you can find out more at Patreon.com/SciShow.
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