Neurology and vocal imitation

["Dr. John Skoyles" <skoyles@GLOBALNET.CO.UK>]

Echololia and vocal imiation are key clinical neurophysiological phenomena.
Our understanding of them depends, however, upon our understanding of the
processes that enable the brain to transform the sounds of spoken words
into the motor commands. At present, the nature of this process has
attracted no scientific explanation either from neurologists, speech
scientists, linguists or those seeking to understand the origins of
language. Last week, I have proposed a theory that makes vocal imitation a
trivial property of speech and speech circuits while linking it in with the
origins of speech in the commentary ejournal Noetica.
http://psy.uq.edu.au/CogPsych/Noetica/OpenForumIssue9/

Since it is a commentary journal, those with experience of echololia might
like to submit commentaries upon it from a clinical perspective.

Here is its abstract:

Mirror Neurons and the motor theory of speech.
Dr. John R. Skoyles
skoyles@globalnet.co.uk
http://www.users.globalnet.co.uk/~skoyles/index.htm

Mirror (imitation) neurons have recently been discovered in the homologous
area to the Broca area in monkeys (Rizzolatti, Fadiga, Gallese & Fogassi,
1996; Rizzolatti & Arbib, in press; Gallese, Fadiga, Fogassi & Rizzolatti,
1996). How might the existence and evolution of speech link to them? Here I
argue that informationally the one unique feature of human speech is that
it is a vocabulary-based communication. As such, its existence requires
that human infants can directly learn from overheard speech thousands of
words in a short time by direct imitation. Cognitively, how infants vocally
imitate overhead words is unexplained. In a revised motor theory of speech
I tackle this problem. The motor theory of speech arose to explain why
speech (in the form of phones) is characterised by motor articulation
information. Originally, it did so in terms of enabling vocal mimicry and
word perception (Liberman, 1957, p. 122). Subsequently, the imitation role
was dropped; I restore it. Speech, I suggest, contains motor information so
that infants can quickly imitate all its thousands of words merely from
hearing them. Vocal imitability is created by a cognitive trick involving
speech motor goals: these goals are always innate high-level auditory
processing categorial invariants (innate and processed in the Wernicke's
area). Because they are innate, these goals are easily extracted by infants
from speech. This allows an infant's motor system to duplicate them and so
duplicate vocalisations. This gaol duplication occurs in imitation circuits
(using mirror neurons in the Broca's area).