Giacomo Rizolatti and Laila Craighero, Mirror Neuron: a Neurological Approach to Empathy, [in:] J.-P. Changeaux, A.R. Damasio, W. Singer, Y. Christen (eds.), Neurobiology of Human Values, Springer 2005, pp. 107-124.
Thesis 1: There is a neural mechanism (,,mirror mechanism’’) that enables individuals to understand the meaning of actions done by others, their intentions, and their emotions, through activation of internal representations coding motorically the observed actions and emotions.
Thesis 2: This neural mechanism played a fundamental role in evolution of altruism, supporting moral norms based on a general concept of ,,The Golden Rule”.
(b) Experimental setting
Experiment 1: Mirror neurons were recorded while monkey was observing a ,,noisy” action (e.g., ripping a piece of paper) and then it was presented with the same noise without seeing the action. The results showed that a large number of mirror neurons, responsive to the observation of noisy action, also responded to the presentation of the sound proper of that action, alone. Response to the white sound or to the sound of other actions were absent or much weaker than responses to the preferred action.
Experiment 2: Mirror neurons were tested by introducing a screen between the monkey and the location of an object. The monkeys were tested in four conditions: (1) the experimenter is grasping an object; (2) the experimenter is miming grasping, and (3) and (4) the monkey observes the actions of (1) and (2) but the final critical part of them (hand-object interaction) is hidden by a screen. The results showed that more than half of the tested neurons discharged in the hidden condition. Mirror neurons typically do not fire during the observation of mimed actions.
Experiment 3: Functional imaging study in humans consisted of olfactory and visual runs. In the olfactory runs, individual inhaled disgusting and pleasant odorants. In the visual runs, the same participants viewed video-clips of individuals smelling a glass containing disgusting, pleasant and neutral odorants and expressing their emotions. The results showed that the same sector within the anterior insula that was activated by the exposure to disgusting odorants was also activated by the observation of disgust in others.
2. Critical comments
1) The idea that when individuals observe others, they enact their actions inside themselves and share their emotions is a plausible one. However, it seems that possessing the above-mentioned biological mechanism is not a sufficient condition of acting altruistically. The presence of an unhappy person may compel some individuals to eliminate the unpleasant feeling determined by that presence, by acting in a way that is not necessary pleasant for the unhappy person.
2) Despite the fact that disgust is usually understood as an emotion that is correlated with a breach of moral rules, in the experimental setting this emotion was not correlated with such an action. It would be interesting to see if the same results were acquired when such an experiment is carried out.