Mirroring NeuronsEmpathy triggered in brain when others’ actions observed

By David Rogers

We all know what it’s like to feel another’s pain. The sight of somebody accidentally pounding his hand with a hammer or weeping for the death of a loved one hurts us, too. How can this be?

Many neuroscientists think they know. Nearly two decades ago a team of scientists at the University of Parma led by Giacomo Rizzola� i made an astonishing discovery: they found brain cells that fi red when an experimental monkey performed an action and when it watched another monkey do the same, even when the observing monkey wasn’t moving.

Rizzola� i and his team dubbed these cells “mirror neurons” for the way they refl ect the brain states of others, and they are a hot topic of discussion and debate among psychologists and neuroscientists. Dr. V. S. Ramachandran, a neuroscientist at the University of California of San Diego, published an essay in 2000 predicting that “mirror

neurons will do for psychology what DNA did for biology.” But what does this have to do with empathy?

Marco Iacoboni, a neuroscientist at the University of California, San Diego, is one of several mirror neuron researchers who have proposed a simple mechanism for explaining empathy through the actions of mirror neurons. When we see emotion-laden actions, he explains, our mirror neuron systems automatically simulate what’s happening in the motor centers of the other person’s brain without actually causing us to execute the motions. This gives us an immediate sense of what sensations accompany the bodily actions of the other person. By another associative link, our brains can make a rough copy of the emotions accompanying these sensations. The sight of a smile, for example, is associated via the mirror neuron system with the sensation of smiling, and the sensation of smiling is associated in

turn with the feeling of happiness—or amusement, depending on the context.

We can also, of course, consciously imagine what somebody else is feeling. But the mirror neuron system provides a more direct link from another person’s emotional state to our own. We feel what the other person feels, weakly, perhaps, but immediately, automatically, without conscious refl ection.

“There is a fabulous quote from Adam Smith [in his] Theory of Moral Sentiments,” Iacoboni said in a telephone interview. “When we see a stroke aimed and just ready to fall upon the leg or arm of another person, we naturally shrink and draw back our own leg or our own arm, and when it does fall, we feel it in some measure, and are hurt by it, as well as the suff erer.’”

For Iacoboni, the key feature of the passage is Smith’s grasp of empathy’s automatic quality. We can hardly help

it. “It’s a beautiful description of the automaticity of empathy and what we think mirror neurons actually provide.”

The most basic function of the mirror neuron system is to help us understand what’s happening inside other people’s heads by observing external cues, both their own actions and various other facts of the situation, and we automatically take this intuitive knowledge into account when we navigate social situations.

But we can respond further to this intuition in two ways. The emotional centers of our brain can engage to make us feel as the other person does—if what we’re seeing is an expressive action, like smiling, or environmental event, like Adam Smith’s hypothetical blow to the arm or leg.

On the other hand, if what we’re seeing is a goal-directed action, we can respond to our intuitive knowledge of the other person’s motor neuron activity by acting it out ourselves—making the internal simulation an external reality.

Some researchers focus on the role of the mirror neuron system in strengthening social bonds, most importantly through empathy. These researchers want to know how is it that we automatically feel as others do, and their theory, as we’ve seen, can be applied in interesting ways to account for esthetic experience and for social defi cits in autistic patients, among other things.

Others, Ramachandran included, emphasize the role of the mirror neuron system in imitation—acting as others do—and therefore in enabling complex imitative learning and language, two abilities that are virtually unique to humans and form the core of human cultural activity.

Many questions about the mirror neuron system remain to be answered. Neuroscientists don’t yet know, for instance, how we get our mirror neurons – are they “hardwired” at birth, or do they develop as we do? One plausible explanation favored by many is that they arise when infants associate their own observed actions and sensations with both the pa� erns of motor neuron activity behind them and the feelings associated with them.

And neuroscientists have only begun to describe the complex ways in which mirror neurons interact with other brain systems to generate a wide array of abilities and behaviors. The fi eld of mirror neuron research abounds with hypothetical mirror neuron models—most of them, of course, highly speculative—of a wide variety of social phenomena.

For instance, Vi� orio Gallese, one of the original researchers at the University of Parma, recently teamed up with David Freedberg, an art historian at Cornell University, to argue that the mirror neuron system might make major contributions to the responses viewers feel both to representational and abstract art.

Representational art portraying human fi gures, they write, would aff ect a viewer more or less like any real visual scene, activating mirror neurons associated with the actions and postures of the scene’s human fi gures. This would allow us, fi rst of all, to rapidly develop an understanding of the intentions and desires of the people in the artistic scene. It would also allow us to empathize with them just as we would with people presented to us in the fl esh, transferring their emotions from the canvas or marble to ourselves by simulating their bodily states and using this simulation to bring out the associated emotional responses.

Theories like this are fascinating on their own. But the mirror neuron theory of empathy and social cognition may also fi nd psychiatric uses, explains Dr. Arthur Glenberg, a cognitive psychologist at Arizona State University. Since the ability to understand the intentions of others, and to empathize with them, is impaired in autistic patients, some researchers have proposed that problems in the mirror neuron system lead to the social impairments suff ered by people with autism.

So far, research on this possibility has proved inconclusive. Experimental

fi ndings are compatible with a mirror neuron theory of autism, but they are not overwhelmingly favorable. Ethical and practical problems, says Glenberg, make for slow progress in this area. Finding autistic patients able and willing to undergo brain scans is diffi cult.

But Glenberg says that “a root problem” in showing that malfunctions in the mirror neuron system contribute to autism is that fMRI, the main tool of mirror neuron research on humans, can show that two processes, like abnormal mirror neuron activity and poorly social behavior, are correlated — they occur together – but it cannot show that one causes the other.

This correlation between social problems and mirror neuron system dysfunction in autistic patients can be explained in three ways, Glenberg says. Altered behavior — such as a

lack of interest in facial expressions — could be caused by a problem elsewhere in the brain, and this might in turn disrupt the development of the mirror neuron

system. Or a problem elsewhere in the brain might be directly causing both the altered behavior and the defi ciencies in the mirror neuron system. Finally, of course, a faulty mirror neuron system could indeed be a cause of the altered behavior associated with autism.

However, even if the relationship between mirror-neuron dysfunction and social defi cits in autistic patients cannot be shown to be causal, mirror-neuron activity still might provide a medically useful biological marker of the severity of autism, as well as of other mental illnesses.

Iacoboni agrees. “Because psychiatric disorders, all of them, have some kind of a social component… mirror neurons must be responding diff erently in these patients,” he said. “So can we actually use this system as some kind of a biomarker of the disease? That would be really a cool thing to do.”

“Mirror neurons will do for psychology what DNA did for biology.”

– Dr. V. S. Ramachandran, Neuroscientist , University of

California of San Diego,

Since its discovery nearly two decades ago, the mirror neuron system—a brain system that fires both when we ourselves perform an action and when we observe another person act in the same way—has been put forward as a key component in a variety of complex mental processes that neuroscientists hope to explain.

Among a host of other functions, the mirror neuron system may interact with other parts of the brain, especially areas governing emotion, to contribute to esthetic experience. Vi�orio Gallese, one of the scientists who discovered mirror neurons at the University of Parma in the early 1990s, recently co-wrote an article with David Freedberg, an art historian at Cornell University, in which the two suggest that the mirror neuron system might play a role in the emotional responses elicited by both abstract and representational art.

Representational art portraying human figures, they write, would affect a viewer more or less like any real visual scene, activating mirror neurons associated with the actions and postures of the scene’s human figures. This would also allow us to empathize with them just as we would with people presented to us in the flesh, transferring their emotions from the canvas or marble to ourselves by simulating their bodily states and using this simulation to bring out the associated emotional responses.

But for Dr. Claudia Mesch, an art historian at Arizona State University, any approach to understanding esthetic appreciation can go wrong if it neglects the

immense complexity of a person’s response to a work of art. For her, mirror neuron researchers have at best only told a tiny piece of the whole story.

She points out, during an interview in her Tempe office, that where the mirror neuron system acts automatically, responding emotionally to any work of art o�en requires plenty of background knowledge of its historical context combined with conscious reflection. O�en, she adds, artists try to challenge the viewer’s understanding of a work of art by making it difficult for them to grasp intuitively what an actor or a painted or sculpted figure is thinking and feeling.

Foiling the viewer’s mirror neuron system in this way might make him or her step back and think about what the artist means to convey. “It forces [you] to separate yourself from yourself, and to be critical of your position,” she explains.

Dr. Marco Iacoboni, a neuroscientist at the University of California, Los Angeles who is a leading mirror neuron researcher, certainly doesn’t deny the complexity of the suite of brain activities mirror neurons seem to contribute to, and he says that he himself takes care to emphasize that “mirror neurons can’t do everything themselves.” They interact with many other brain regions, including those responsible for abstract conscious reflection, he says, in ways that are barely understood. Some studies indicate that interaction between the mirror neuron system and conscious reflection is bidirectional in exactly the way Mesch implies it must be.

Iacoboni goes on to

describe an experiment of his own in which mirror neuron system activity was found to change when human subjects observed a hand grasping a glass in two different contexts, one of which suggested that the person intended to take a drink and one which suggested that the person intended to clear the glass from the table. The action in each case was exactly the same but the mirror neuron system activity differed, suggesting that higher-level understanding of contextual cues influenced mirror neuron activity, and vice versa.

But how could the mirror neuron system contribute to the appreciation of abstract art, which by definition doesn’t depict recognizable objects, including the human figure? Gallese and Freedberg suggest that part of the meaning of abstract art involves mirroring the artistic actions of the artist him- or herself: when you look at abstract art, you feel a li�le like the artist did when he or she created it.

Works of art, they reason, are “the visible traces of goal-directed movements,” and therefore act as a record of the gestures that produced it. That might lead us to infer – perhaps empathetically – what the artist saw or hoped to see in producing the work. In many works of abstract art –Jackson Pollock’s paintings come to mind—this record can be read fairly easily.

Dr. Glenberg, a cognitive psychologist at Arizona State University, admits that he is “skeptical” of this notion, though he knows Gallese personally and watched an early presentation on the idea in Italy. It’s asking an awful lot of our perceptual systems, he thinks, to give

them the task of puzzling out the actions behind an object of abstract art.

On the other hand, seeing an abstract artist actually at work, he suggests, might allow the mirror neuron system to learn what kinds of actions go into creating such a work and thus allow them to intuit the creative gestures behind it. And art experts, who o�en appreciate abstract art more than ordinary folks, might acquire their sensitivity in exactly this way, through many years of study and first-hand experience with art and artists.

Dr. Mesch, too, is a li�le skeptical, again emphasizing the importance of conscious reflection in understanding art of any kind. But she also points out that the capabilities of the mirror neuron system might explain the importance of viewing a work of art directly rather than simply reproduced in a book or as a print. She points to a picture of a Jackson Pollock painting: “we have to go and stand in front of it at [the Museum of Modern Art in New York] and get a sense of that work as a physical object” she says, in order to understand what the act of creation was like for Pollock.

If all we see is an image of the work printed in a book, our mirror neuron systems are deprived of visual cues that they need to grasp the motions involved in creating it. Size, for example: the picture of Pollock’s painting measures a few inches to a side, but the real thing is several feet tall. Texture is also important. Art connoisseurs tend to get up close to paintings to peer at the brushstrokes—or in Pollock’s case, at the pick-up-sticks topography of the layered spa�ers.

Art: Mirrored in the Brain?