a group of researchers in Italy were
investigating motor neuron activity
in a Macaque monkey brain when
they made an accidental discovery
that may provide an explanation for
how empathy, consciousness, language, and thought work in the human brain. Amazingly, their research has been mostly ignored.
WHEN A MACAQUE MONKEY wants to lift its arm, neurons in the premotor cortex of its brain fire, sending the ‘move’ signal to its arm muscles. The Italian researchers — led by Giacomo Rizzolatti at the University of Parma — were studying this process by using a surgically-implanted electrode that would show neurons as they activated on a screen.
The team performed several studies showing that the neurons in the premotor cortex did indeed light up when the monkey moved its arm. But then something strange happened: the screen began lighting up when the monkey wasn’t moving at all.
These ‘phantom’ activations seemed completely random until one of the researchers noticed that every time the test monkey’s neurons had fired, another monkey across the room had been moving its arm. The test monkey’s neurons fired as it was merely watching the other monkey move!
The discovery
The researchers discovered what they call ‘mirror neurons,’ and when they activate, the monkey appears to be "imagining" itself doing something that it is actually watching another monkey do.
It turns out, in fact, that mirror neurons aren't the only way the brain uses these phantom neuron activations. In 2002, Rizzolatti’s team expanded on their findings and discovered something even more amazing: when the monkey looks at an object -- any object at all -- the motor neurons corresponding to the finger, arm, and hand movements that would be required to grasp the object activate. The amazing thing is that these neurons activate even when the monkey doesn’t actually pick up the object.
What if these phantom activations are actually the brain’s way of running internal simulations of options and determining the best outcome? Maybe this is how decisions are made in the brain. It clearly makes sense in the case of muscle movement, but the same processes could be behind much more interesting things, like thought and language.
Communication
Communication by language has long been considered the pinnacle of human-ness, the primary differentiator that is uniquely human and makes us special. But if you look at the way the macaque monkey brain mimics muscle movements, and then look at the processes behind language creation and understanding in the human brain, you see striking similarities. The way a monkey can “understand” another monkey’s movements and the way it can ‘think’ of how to grasp an object are direct parallels to the way the two speech centers, Werneke’s and Broca’s areas, work in the human brain to produce language. In fact, the area of the monkey brain the researchers were investigating is the monkey analog of Broca’s area in the human brain. It seems possible that language is just a higher level organization system for normal activity that would have been expressed in the brain anyway. What if consciousness is just an illusion created by the expression of mirror neurons interacting with the language centers of your brain?
Maybe the monkey brain predetermines which neurons to fire in the same way the human brain predetermines which words might be required to produce a sentence. Maybe these neurons are behind the experiences of empathy, understanding, and love. Maybe what we call thought is just the expression of language in our brains without actually speaking in the same way the monkey brain ‘expresses’ movement in its brain without moving.
Maybe these neurons are the missing piece to the puzzle of consciousness and thought. •
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Further reading
The original papers published by Rizzolatti and his team.
Premotor cortex and the recognitionof motor actions
Cognitive Brain Research, 1995. Rizzolatti, et al.
The monkey photo on this page is not of a macaque; it's an infant orangutan. Some photography and illustrations have been kindly provided by Shutterstock.com.