Oculo-auricular phenomenon

The oculo-auricular phenomenon, first described by Kinnier Wilson in 1908,^[1] is the phenomenon of an extreme lateral gaze inducing a slight but perceptible backwards movement of the upper part of the pinna.^[2] It is a muscle synergy involving the Abducens innervated lateral rectus muscle, an external muscle of the eye, and the facial innervated posterior auricular muscle, an external muscle of the ear.^[3] Wilson's phenomenon had attracted attention at the time because of his renown and for its implications regarding Darwin's theory of natural selection.^[4] According to (Urban 1993), "In patients with brainstem disease abnormal transverse auricular muscle coactivation is characterized by absence of activity in one or both ear muscles during lateral gaze in either or both directions."^[5]

References

1. Caplan, Louis R.; Hopf, Hanns C. (2012-12-06). Brain-Stem Localization and Function. Springer Science & Business Media. ISBN 9783642781728.
2. Schmidt, D.; Thoden, U. (1978-06-19). "Co-activation of the M. transversus auris with eye movements (Wilson's oculo-auricular phenomenon) and with activity in other cranial nerves". Albrecht von Graefes Archiv für Klinische und Experimentelle Ophthalmologie. Albrecht von Graefe's Archive for Clinical and Experimental Ophthalmology. 206 (4): 227–236. doi:10.1007/bf02387334. ISSN 0065-6100. PMID 308327. S2CID 26892630.
3. Wagner, A. "Oculo-auricular phenomenon and its value in neurologic diagnosis".
4. Hackley, Steven A. (2015-10-01). "Evidence for a vestigial pinna-orienting system in humans". Psychophysiology. 52 (10): 1263–1270. doi:10.1111/psyp.12501. ISSN 1469-8986. PMID 26211937.
5. Urban, P. P.; Marczynski, U.; Hopf, H. C. (June 1993). "The oculo-auricular phenomenon. Findings in normals and patients with brainstem lesions". Brain. 116 (3): 727–738. doi:10.1093/brain/116.3.727. ISSN 0006-8950. PMID 8513400.