Location of efferent neurons to the labyrinth of the green tree frog (Hyla cinerea). A horseradish peroxidase study.

The origin of centrifugal fibers to the labyrinth was determined by application of horseradish peroxidase to the severed octavus nerve of the green tree frog (Hyla cinerea). Labeled neurons were found exclusively in the nucleus reticularis medius of the reticular formation ipsilateral to the injection site. In particular, no retrogradely labeled neurons were found in the octavus nuclei.