Like many observers of the neurosciences from other fields, I have watched the debate about the function, origin, and nature of ‘mirror neurons’ with no small amount of interest. Since their discovery in the early 1990s by Giancomo Rizzolatti and his research group at the University of Parma, the ‘mirror system(s?)’ in primates and humans have been extensively explored and discussed.
For anyone living under a neurosciences rock, ‘mirror neurons’ are typically premotor or parietal neurons that are active both when a subject perceives and executes an action. In a host of research projects which I’ll probably try to discuss later (I wrote a lengthy piece on them that was recently rejected by a major anthro publication, and I’m considering posting the original in the anthropology open source archive and then doing a MAJOR revision to seek publication elsewhere). Anyway, mirror neurons have been linked to action understanding, empathy, imitation (a personal interest), language, and ‘mind reading’ (not a sixth sense, but the abiltity to understand other’s intentions and perceptions).
A new paper by Caroline Catmur, Vincent Walsh, and Cecilia Heyes (one of the really innovative scholars working on mirror neuron research) in Current Biology has some fascinating implications for neuroanthropology(abstract or pdf download). In particular, the article suggests, in the words used in the abstract:
…it is unclear how mirror neurons acquire their mirror properties—how they derive the information necessary to match observed with executed actions. We address this by showing that it is possible to manipulate the selectivity of the human mirror system, and thereby make it operate as a countermirror system, by giving participants training to perform one action while observing another. Before this training, participants showed event-related muscle-specific responses to transcranial magnetic stimulation over motor cortex during observation of little- and index-finger movements. After training, this normal mirror effect was reversed. These results indicate that the mirror properties of the mirror system are neither wholly innate nor fixed once acquired; instead they develop through sensorimotor learning. Our findings indicate that the human mirror system is, to some extent, both a product and a process of social interaction [please note I’ve removed citation numbers that appear in the abstract].
Continue reading “Mirror effects in neurons learned?”