‘‘DIE LOKALISATION IM GROSSHIRN”’ 495 
nerve trunk only may be stimulated, and it may be urged that 
the reflex response occurs without the access of any other affer- 
ent impulses. Stimulation of a particular afferent nerve under 
constant conditions generally elicits a particular reflex response. 
Hermann embodied these facts in his statement of the law of 
specific response to stimulation. But the reflex response of a 
skeletal muscle involves other afferent impulses than those 
arising from stimulation of a given afferent nerve in a given 
manner, which may be regarded as the particular afferent im- 
pulses which elicit the response. Tschiriew showed that even 
the form of the curve of a single muscle twitch elicited by stim- 
ulation of the motor nerve to the muscle is modified by section 
of the afferent nerves from the muscle. Afferent impulses from 
the muscle itself are involved in its reflex response arising from 
stimulation of any other afferent nerve. And if the muscle is in 
situ, other, antagonistic, muscles are involved as well as the 
prime mover. The deportment of the antagonists is controlled 
by afferent impulses, arising in part in the antagonists them- 
selves, and in part in other regions, such as the joints. The 
analysis of even the simplest reflex response in an intact animal 
shows that it is far from simple in the mechanism involved. 
One should not lose sight of all the other phenomena following 
the application of the one form of stimulus to a given limited 
area or location which is said to elicit the reflex. To lose sight 
of what follows is to get a very imperfect idea of even the sim- 
plest reflex response of a skeletal muscle. In general, it is the 
accessory afferent impulses, if one may so speak of them—the 
impulses arising from sensory fields other than the limited one 
to which a given stimulus is applied—which makes the reflex 
response biologically adequate, to use Edinger’s phrase. That 
a reflex response may occur in the absence of some of the affer- 
ent impulses normally entering into its control does not affect 
the main statement. It is possible that under experimental 
conditions a reflex could be elicited which would involve affer- 
ent impulses from one and only one sensory field. But it is 
extremely doubtful whether such a condition ever arises in the 
intact animal. When we consider the liberation of one reflex 
