James Michael Howard <jmhoward at anthropogeny.com> wrote in message news:<fr9bj0d94bnbp56p66d7tulb5t3lcbkcrh at 4ax.com>...
> On Tue, 31 Aug 2004 19:44:26 -0400, Wolf Kirchmeir
> <wwolfkir at sympatico.ca> wrote:
>> >ray scanlon wrote:
> >
> >> David Longley writes:
> >>
> >>
> >>>Don't you think sleight-of-hand and metaphysics deserves derision?
> >>
> >>
> >> Well, then let's drop all the sleight-of-hand and metaphysical
> >> prejudices and talk about the brain.
> >>
> >> Since the neural net (interneurons) appeared in Cnidaria, what has
> >> changed? For one thing, the DNA has evolved to a point where it is
> >> able to construct a whole series of motor program generators, groups
> >> of neurons that when
triggered produce a motor act. These generators
> >> can be modified by experience but they are not learned. We are born
> >> with them.
> >>
> >> The location in the nervous system of some of these motor program
> >> generators can be more or less specified.
> >[...]
> >
> >Are you claiming that we are born able to walk?
> >
> >The development of the motor cortex is actually a good deal more
> >complicated than you appear to believe. Even in animals that can walk a
> >few minutes after birth. So I would prefer to say that we are born ready
> >to learn certain things. If that learning is impeded, we may never learn
> >to do the things we are "born with."
>> Walking awaits myelinization of the pertinent nerves; this causes the
> delay.
Might be that walking awaits connection of the proper synapses. In
babies, the #synapses in the brain increases by 500% or so over the
course of year 1.