Abstract
The following thesis contains a record of the
results anatomical and physiological of a number of
experiments undertaken at the suggestion of Professor Schafer with a view to determine the path
pursued by the fibres of the pyramidal tract in
their course from the large pyramidal cells in the
cerebral motor cortex to their termination in the
lower levels of the brain and spinal cord, but more
particularly their mode of ending in relation to
the nuclei of the cranial nerves in the mid-brain,
pons and medulla oblongata. Although this - the
motor path - has been more carefully investigated
and is probably better understood than any other
tract or path in the central nervous system, still
much remains to be discovered, especially regarding
the terminal connections of its fibres with the
motor nuclei of the cranial nerves and with the
cells in the anterior horns of the spinal cord.
Writing on this matter, Barker says:- "The exact
place where the fibres for these nuclei" (cranial
motor nuclei) "leave the main bundles" (of the
pyramidal tract) "and the exact path which they
follow to the nuclei have not as yet been fully
determined." . . . "The statement that nerve fibres
from these bundles do pass to these nuclei is based
mainly, but not solely, upon clinical experience,
physiological experiment, and analogy." That is
to say, the anatomical connections of the fibres of
the pyramidal tract with the cells of the anterior
cornua of the spinal cord and of the cranial motor
nuclei have never yet been satisfactorily established, and it was with the object of throwing some light
if possible on this subject that the work embodied
in the present thesis was undertaken.
