Thanks!

Marcy marcyatwork at hotmail.com
Sat Feb 17 16:03:52 EST 2001


Wow, thanks for the link! This is going to prove very useful in my research!
Marcy Italiano

Shamim Khaliq <shamimkhaliq at hotmail.comTakeThisOff> wrote in message
news:3a8c189f_3 at news.intensive.net...
> these two quotes imply it's an aspect of central imagery/representation,
not
> peripheral processes, i think. but if you're interested it quotes some
> reviews on the topic that might be interesting to read.
>
> "Amputated subjects, for example, report feeling movements of their
phantom
> limb, and seem to have a clear image of their intended action (for
complete
> description, see Schilder, 1935). Similar feelings are reported by
patients
> with deafferented limbs (due to peripheral deafferentation or other
causes).
> They may describe their intended action in great detail while no actual
> movements can be observed from the outside (e.g., Duchenne de Boulogne,
> 1855, Jeannerod et al, 1984). These data suggest that, in the condition of
> executed action, the content of the motor representation would not reach
> consciousness because it would be cancelled as soon as the corresponding
> movement is executed (perhaps by the incoming signals generated by
execution
> itself). By contrast, in the condition of motor imagery, where execution
is
> purposively blocked or delayed, the representation would be protected from
> cancellation and would become accessible to conscious processing. "
> (http://www.cogsci.soton.ac.uk/bbs/Archive/bbs.jeannerod.html)
>
> Patients who have been paralysed centrally report no effort trying to move
> paralysed limbs (Mach, 1906 ; Gandevia, 1982 ), while patients or
> participants paralysed peripherally use more effort to "move" their
> paralysed limbs (Gandevia and McCloskey, 1977 ). Force judgements of
> weakened muscles tend to be overestimated independent of actual muscular
> tension (Holmes, 1922 ). There's an increase in duration of a
goal-directed
> movement when this movement becomes more difficult. This occurs even
without
> visual feedback (Prablanc et al, 1979 ) so it's not due to more time
needed
> to process visual feedback but neural coding of the movement during the
> preparatory stage (Jeannerod, 1986a ; see Meyer et al, 1990  for a
review).
>
>
>
> --
> Shamim Khaliq shamimkhaliq at hotmail.com <http://shamimkhaliq.50megs.com/>
> Marcy <marcyatwork at hotmail.com> wrote in message
> news:3GUh6.138768$V22.27989982 at news4.rdc1.on.home.com...
> ...
> > Phantom limbs... Where is the information coming from? If the lower leg
is
> > amputated at the knee, does the sensation of an itchy foot come from the
> > nerve endings at the tip of the knee (point of amputation), or an
> > interpretation the brain is making based on the body image. If the
latter
> is
> > true, how does this affect all sensations we feel? Can that be measured?
> ...
>
>







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