Embracing Our Inner Ape

I once had a colleague who had a distracting habit. Whenever I spoke to him, he would inaudibly mouth my words, milliseconds later. There was no doubt that he was listening to me, because he always got my meaning, but even while listening he would simultaneously be moving his lips. I was and am convinced he did not know he was doing this. And good thing, too, because otherwise I would have felt that he was, well, mocking me.

Well it turns out that he was mocking me, though not in a malevolent way. What he was doing with his lips was part of the basic act of perception, which appears to be inextricably tied up with the brain cells that control movement. In order to understand me, he was “trying on” my actions for fit—or “reliving” them. We all do this kind of cognitive processing, though most of us do it internally, where it’s not annoying. Indeed, new research is demonstrating that the brain is hard-wired for aping, and that such mimicry is essential to our very existence as social beings.

Psychologists used to think that perception and movement were two completely separate processes, lodged in different regions of the brain. The common wisdom was that we perceive the world with our eyes and ears and so forth, and send that information to the mind, which in turn instructs the limbs and lips to act in certain ways. But apparently it’s not so tidy. According to Rutgers University psychologists Gunther Knoblich and Natalie Sebanz, the latest evidence suggests that it doesn’t matter whether we’re performing or observing: Each mental task activates the same “common codes” in the mind.

This is why some undisciplined soccer fans twitch and squirm in their seats when they watch their favorite striker fake out an opponent. (It doesn’t explain their undisciplined behavior after the game.) Animal studies also provide biological evidence for common codes: The same nerve cells in monkeys’ brains will fire off whether the monkey grasps an object or watches someone else grasp it. These cells are called “mirror neurons”: Doing is a reflection of watching, and vice versa.

The brain’s matching of perception and movement can be very precise. For example, the brains of highly trained dancers are quicker to click on their internal dancing scripts if they are watching the kind of dance they are trained in—say, ballet. And there is even more activity if the dancers are watching videos of themselves dancing. Knoblich and Sebanz speculate that this selective activation of the internal repertoire is what allows us to distinguish our own actions from those of others. Seeing ourselves in action has greater resonance in the neurons, even though we don’t see ourselves all that often. There are also common codes for hearing: Our brains respond to our own clapping or piano playing more than to someone else’s, because our particular clapping or piano playing “style” in encoded in the mind.

Knoblich and Sebanz thought that the common code hypothesis might explain how we do things together: things like playing duets and rowing a canoe—all the things that make us social animals. They decided to take a look at this idea in the laboratory. They devised a simple task in which participants, working together, had to push certain buttons in response to red and green lights. Then they tried to confuse one of the participants with another stimulus. They found that both participants were thrown off by the distraction—and therefore more hesitant in their responses. It appears, the authors say, that people cannot help aping what others do, even when doing so hurts their own performance.

Studies of actual brain waves confirm this. When participants were asked to wait their turn but had to watch someone else, it took much more mental effort not to act than when they were alone. The authors take all this evidence, reported in the journal Current Directions in Psychological Science, to mean that perception-action links are crucial building blocks of all social understanding and social interaction. Indeed, it may be that over eons the demands of being social have shaped basic psychological processes like perception, action and cognition.

The scientists believe this psychological model might one day offer insights into disorders of social function, like autism and schizophrenia. For the time being, it should at least help us to better appreciate the complexity of a simple piano duet, or to better tolerate the idiosyncrasies of sports fans and colleagues.

For more insights into human nature, visit the Association for Psychological Science website at www.psychologicalscience.org.