Cells That Read Minds?
What the myth of mirror neurons gets wrong about the human brain.
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These are fascinating and important results. But they tell us about the functions and connections of large portions of the brain, not about individual neurons. Moreover, this mirror system is quite separate from the parts of the brain that are activated in language and everyday social understanding. And this kind of large-scale brain organization, like the tuning of individual neurons, is itself likely the result of experience.
A fourth misconception perpetuated by the myth holds that a single type of cell can be responsible for a single type of experience. Could the human "mirror system" work because it's made up of lots of mirror neurons? No. Experiences and behaviors are never going to be the result of just one kind of cell, or even several kinds. More than 40 years ago, scientists used electrodes to record from individual neurons in the visual system of cats. They found a group of cells that responded distinctively to certain kinds of shapes, and they called them "edge detectors." You might think we see edges because our edge detectors fire. But decades of research have shown that the real picture is much more complicated. Something as simple as seeing an edge results from a very complex pattern of interactions among hundreds of different types of neurons. You can imagine how many types of interacting neurons it would take to drive a social behavior.
The intuition that we are deeply and specially connected to other people is certainly right. And there is absolutely no doubt that this is due to our brains, because everything about our experience is due to our brains. (It certainly isn't due to our big toes or our earlobes.) But it's little more than a lovely metaphor to say that our mirror neurons bring us together.
Photograph of Sri Lankan monkeys by Rob Elliott/AFP/Getty Images.