The link between seeing and experiencing -- the idea that one triggers the other -- is currently attributed to the "mirror neuron network." In 1996 Vittorio Gallese, Giacomo Rizzolatti, and others found that neurons in the ventral premotor area F5 of the macaque monkey responded both when the monkey executed a particular movement (such as reaching for a peanut) and when the monkey observed an experimenter performing the same movement. These neurons came to be called "mirror neurons" because the neurons in the observing monkey appeared to mirror the same neurons active in the person executing the action. Their findings were quickly applied to humans, and hundreds of experiments involving fMRI scans have been used to try to determine whether mirror neurons exist in the human brain. A debate about the existence of mirror neurons -- and their function if they exist -- has been raging for the last twenty years (see Dinstein et al "A Mirror Up To Nature," Lingnau et al 2009, Dinstein 2008, and Hickok and Hauser 2010). Nonetheless, the most recent experiments, as outlined in the "Mirror Neuron Forum," a discussion between Vittorio Gallese, Marco Iacoboni, Gregory Hickok, Morton Ann Gernsbacher, and Cecelia Heyes (2011) do indeed suggest the existence of mirror neurons in humans, and propose a complex role for them -- not only as decoders of observed action, but of aural information as well. Christian Keysers and Valeria Gazzola report the existence of mirror neurons in the human brain (2010:353) based on the work of neurosurgeons Itzhak Fried and Mukamel, who found, while trying to help patients with severe epilepsy, eleven neurons in humans that discharge during both the execution and observation of frowning, smiling, and certain finger and hand movements (Mukamel et al 2010). Keysers and Gazzola explain their finding by referring back to "Hebbian learning," in which "neurons that fire together wire together:" eventually neurons that are involved in both watching and doing become part of the same neural network because they fire together. In other words, they argue that it would be hard for humans not to have mirror neurons given the way the brain creates networks.

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