The Deep Sensibility of the Face

Residual sensibility following various definite peripheral nerve lesions has afforded the material for many original and productive investigations. The contributions of Henry Head and his collaborators have marked an epoch in the study of the peripheral sensory mechanism, and the numerous nerve injuries encountered during the Great War gave added impetus to further experiments. By virtue of their comparative inaccessibility and the scarcity of verifiable clinical lesions, little is accurately known of the sensory distribution of the cranial nerves in man. This is quite true of the sensibility of the face, the cranial nerve supply of which must be the trigeminal or facial nerves or both. Since Sir Charles Bell showed that facial palsy was dependent on a lesion of the seventh cranial nerve, for all practical purposes this nerve, with the exception of its chorda tympani branch, has been regarded as a motor nerve. The nervus intermedius without doubt