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Iacoboni 26
...a very interesting class of mirror neurons codes observed actions that are preparatory or logically related to the executed actions. A „logically related“ mirror neuron is one that, for instance, fires at the sight of food being placed on the table and also while the monkey grasps the piece of food and brings it to the mouth. This class of cells may be part of a neural chains of mirror cells that are important for coding not simply the observed action also the intention associated with it. This intention is achieved through a sequence of simpler actions: reaching for the cup, grasping it, bringing it to the mouth, and then drinking from it.
A really tell-tale feature of the macaques‘ mirror neurons is that they do or not fire at the sight of a pantomime. Performing a grasping action in the absence of an object does not trigger a discharge. This may seem odd to us, but it isn't particularly so, because these monkeys do not typically pantomime.
We humans, however, do pantomime, and indeed our mirror neurons areas are activated by more abstract actions than are those of the monkeys. The several evolutionary steps dividing monkeys from humans can easily account for such difference. A subject for future discussion will be the theory by computational neuroscientists Michael Arbib that mirror neurons at key precursors of a neural systems for language. He proposes that pantomime plays a critical role in the evolutionary progression from the relatively simple mirror neuron system in monkeys to the much more sophisticated neural system that supports the high level of abstraction in human language.
see also:
From Monkey-like Action Recognition to Human Language:
An Evolutionary Framework for Neurolinguistics
Michael A. Arbib
Computer Science Department, Neuroscience Program, and USC Brain Project
University of Southern California
Los Angeles, CA 90089-2520
arbib@pollux.usc.edu; http://www-hbp.usc.edu/
Merlin Donald:
... the changes in the architecture of cognition that occurred during the first two transitions. (Episodic to Mimetic (Pantomime))
At level I, the starting point, representational structure is very simple; the mind had only one way of representing reality - as event perceptions. Therefore, the whole range of complex event representations held by chimpanzees, and by extension australopithecines, is enclosed within a circle, labeled "episodic" (E). The transition from level I (episodic) to level II (mimetic) is also simple to conceive in this way; the entire range of mimetic knowledge, from games and tool making skills to group ritual and standardized gesture, is enclosed within another circle (M). Mimetic representations are metaphoric, rehearsable self-representations built upon episodic knowledge; therefore, by definition, episodic outputs are available to the mimetic representational process. An arrow indicates this access route. This relationship is asymmetrical: episodic systems cannot model the outputs of the mimetic representational system; hence, the arrow is unidirectional.
Note that the new representations emerge at the top of the system; cognitive structures that formerly served as the "central processor of mind are superseded, and encapsulated, by other structures. This is clearly the case after the first transition; episodic representations could not have been informationally encapsulated in the primate. In apes, episodic event representations are at the cognitive pinnacle; they are supramodal, and it is reasonable to assume that they can access outputs from all sensory modules and thus define the forms of their conscious experience. But, after becoming embedded in a matrix of higher representations at level II, the episodic mind would have be come encapsulated, gradually surrounded by more powerful methods of representing reality, while it continued to produce its traditional outputs. Fodor would have little choice but to place episodic experience in his "central processor" category in apes. But in humans the central processorthat is, the highest, unencapsulated structureseems to have moved elsewhere. The integrative machinery of episodic experience was superseded by higher mimetic structures: sic transit gloria mundi.
Mimetic skill was at the core of the cognitive style of erectus, and it could access all that went before. Therefore, in its time, it must have been unencapsulated; but it too was bypassed and relegated to the cognitive provinces, when the linguistic system emerged at level III, after the second transition.
Although mimetic representations continued to access episodic experience, they could not model linguistic content. Thus, they suffered the same fate as episodic mind and were encircled by a more powerful representational apparatus. Nevertheless, mimesis continues to exist as an independent representational system: for someone lacking language, mimesis remains the highest, or governing, way of representing reality and presumably dominates the forms of conscious experience. But a linguistically able mind will relegate mimesis to a secondary role.
Iacoboni
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