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A little over two decades ago, a research team at the University of Parma in Italy discovered a class of neurons in the macaque monkey that would not only capture the imagination of neuroscientists around the world but would eventually be linked to faculties such as imitation, empathy, and even language.
This unassuming class of neurons, called mirror neurons, was discovered in the motor areas of the brain. Mirror neurons not only produce activity when a monkey performs an action but also fire when the monkey merely observes the researcher perform the same action.
MRI and PET studies have suggested that humans too have a mirror neuron system similar to that found in monkeys, comprising neurons in the prefrontal areas as well as the inferior parietal lobule. The fact that mirror neurons are the only class of neurons as yet known to code for the actions of other people, as well as our own, has led scientists to theorize that they are essential brain cells for social interactions, as well as empathy. When we see someone smiling, for instance, our mirror neurons for smiling fire up, providing us with an almost instinctive understanding of how they must be feeling.
A number of studies have been done on mirror neurons and autism. While many autistic children might excel in math, science, or music, and have an excellent memory for information, they have, among other symptoms, difficulty with social communication and interaction. fMRI studies have shown that children with autism show remarkably reduced mirror neuron activity when they observe emotional expressions, in comparison with controls. Also, the more severe the social deficits of the children, the lesser the activity in the regions containing mirror neurons. Findings such as these have led a number of scientists to conclude that a dysfunctional mirror neuron system might underlie not only the social deficits but possibly also the motor and language deficits observed in autism.
Evolutionary Aspects
If Charles Darwin, the English naturalist who formulated the theory of evolution, were alive today, he would be astonished at the burgeoning studies exploring the evolutionary origins of nearly every aspect of human function, from emotion to language. Darwin's theory states that all organisms not only arise as a result of but also develop due to the accumulation of small, inherited changes selected by nature, that increase the ability of the organism to compete, survive, and reproduce.
The familiar catchphrase "survival of the fittest" encapsulates this idea pretty well. When observing the world through an evolutionary lens, where does empathy fit in? On the surface, empathy seems like an emotion that goes against self-interest. Dig a little deeper, though, and it seems like the opposite is the case.
Researchers believe that the faculty of empathy evolved as it helped our ancestors survive in two separate ways. For one, for any mammalian species to survive, members of the species need to be attuned to the needs of their offspring. Secondly, the human species thrives on interpersonal relationships and cooperation, and we as a group have greater chances of survival if our group members are well taken care of. To paraphrase renowned primatologist Frans de Waal, who studies among other things empathy and conflict resolution in primates, "Empathy is simply enlightened self-interest."
In-Group vs. Out-Group Empathy
We move now to an aspect of empathy that is deeply disturbing, but which, once we draw our own attention to it, we can try and correct. Our empathy seems to be, instinctively, more directed toward people we consider to be within our tribe, rather than to those outside it. It might be that evolution has prepared us as a species to quickly identify who is within our group, so that we might understand what they need better and if necessary protect them from outside threats.
In fact, humans display in-group preference in many distinct ways. We tend to downplay flaws and generally like people more if we perceive them as being within the same group that we belong to; even the emotions of in-group members are perceived more quickly and more accurately than those of out-group members. Studies have found that intergroup discrimination arises more from in-group love and empathy than from out-group hate or vigilance.
Oxytocin, dubbed the "cuddle hormone," is a chemical that, among other functions, helps us bond with other people. Researchers have administered oxytocin intranasally to study its effects on empathy and have found that the hormone enhances the in-group empathy of the participants, while enhancing defensive aggression towards people outside their group.
In a world that is becoming increasingly globalized, it is more important than ever before for us to recognize empathy for the primordial, parochial emotion that it is, and to try and expand our empathy to include everyone from the human race.
References
Rizzolatti G, Craighero L. The mirror-neuron system. Annu Rev Neurosci. 2004;27:169‐192. doi:10.1146/annurev.neuro.27.070203.144230
Dapretto M, Davies MS, Pfeifer JH, et al. Understanding emotions in others: mirror neuron dysfunction in children with autism spectrum disorders. Nat Neurosci. 2006;9(1):28‐30. doi:10.1038/nn1611
De Dreu, Carsten & Kret, Mariska. (2015). Oxytocin Conditions Intergroup Relations Through Up-Regulated In-Group Empathy, Cooperation, Conformity, and Defense. Biological Psychiatry. 79. 10.1016/j.biopsych.2015.03.020.
