The abnormal plantar response that occurs in disease of the pyramidal tract, as described by Babinski,1 consists of a group of simultaneously occurring movements, the most conspicuous of which are dorsiflexion of the big toe, separation—generally associated with plantar flexion of the other toes and eversion of the foot. The reflexes with which the phenomenon should properly be identified are, therefore, the coordinate or purposive reflexes. These reflexes, in addition to exhibiting themselves in simultaneous contraction of a large number of muscles, are like the Babinski response in that they occur exclusively or are especially prominent after the cerebral influence has been removed. Sherrington2 and Riddoch3 give details concerning these reflexes in the "spinal" animal and "spinal" man.
PREVIOUS INTERPRETATIONS OF THE BABINSKI TOE RESPONSE
Among the explanations of the origin and mechanism of the toe response are: Knapp4 attributed the dorsiflexion of the big toe