Injuries of nerves and their consequences - Reflex Sympathetic ...

NEURAL MALADIES OF STUMPS. 359
and necessitated by, the originative act of will, or else are
messages sent to the sensorium from the spinal ganglia
which every act of motor volition excites.
The influence of electrical currents on the nerves of
the stump introduces into our calculations
and puzzling considerations.
certain novel
If we faradise the track of the nerves in or above the
stump, we may cause the lost fingers and thumb to seem
to be flexed or extended, and, what is most remarkable,
parts of which the man is conscious, but which he has not
tried to stir for years, may thus be made to appear to
move to his utter amazement. In one case I thus acted
on the nerves, so as to cause a thumb which for years
was constantly and violently bent in on the palm to
straighten out completely. On breaking the circuit,
without warning, the patient exclaimed that his thumb
was cutting the palm again, and the same result was obtained
by shifting the conductors so as to put the nerves
out of the circuit.
In a case of amputation at the shoulder-joint, in which
all consciousness of the limb had long since vanished, I
suddenly faradised the brachial plexus, when the patient
said at once, " My hand is there again. It is bent all
up
and hurts me." These impressions are correctly referred
by the patient, so that faradisation of the musculo-spiral
the related
or the ulnar gives sensation of movement in
parts. It is of course impossible that the motor nerves
stimulated should convey any impression centrally, and
we must therefore conclude that irritation of sensory
trunks may occasion impressions of muscular motion in
the sensorium.
It would appear, then, that when we will a movement,
there arises coincidently, or from the spinal ganglia
through which it is carried out, impressions as to the
force of the act and the position of the parts which we