Neural Correlates of Empathy in Humans, and the Need for Animal Models

In this review, we summarize the results of two decades of human neuroimaging studies on the neural basis of our empathy for the actions, sensations, and emotions of others. We show how the discovery of mirror neurons in monkeys has set the conceptual stage for interpreting the observation that witnessing the sensations and emotions of others activates brain regions involved in our own sensations and emotions. We review a number of situational factors that are known to influence the magnitude of these vicarious activations to highlight that empathy is a motivated function rather than an automatic process. Finally, we analyse the limits of studying the neural basis of empathy in humans; using noninvasive methods, it is currently impossible to characterize the properties of neurons causing vicarious activations, to assess whether the same neurons are indeed involved in perceiving and experiencing emotions, and whether such activity is necessary for empathy. Overcoming these limitations will require a tighter integration of human and animal neuroscience.