In article <9502241702.AA15112 at mail.ngc.PeachNet.EDU>,
rjl at S1500.NGC.PEACHNET.EDU wrote:
> Help -
>> As I try to help my gross students understand PNS composition I see
> statements that appear contradictory re nomenclature for, and fiber-type
> composition of, peripheral nerves. Your thoughts, for their edification,
> are earnestly solicited.
>I think some of the confusion of which you complain is due to the
difference in the clinical and physiological uses of the terms "sensory"
and "motor" (and mixed) as applied to nerves. In clinical language, a
sensory nerve is one like the sural which supplies only skin. Whereas a
motor nerve (like those you list) is simply a branch to a muscle which
does not also innervate the skin. This distinction has some utility in
physical examination, clinical neurophysiology and histopathology where
one needs to know of specific nerves with a predominance of one type of
fiber in order to diagnose diseases with a predeliction for one type
(among other goals).
As physiologists, we know that (all?) motor nerves contain sensory fibers
from muscle and tendon with the possible exception of some facial muscles
which may rely on skin receptors exclusively for control.
I hope this helps. BTW how "gross" are your students?
Eric Wassermann
