Glabellar reflex
The glabellar reflex, also known as the "glabellar tap sign", is a primitive reflex elicited by repetitive tapping on the forehead.[1] Subjects blink in response to the first several taps. If the blinking persists, this is known as Myerson's sign, and is abnormal and a sign of frontal release; it is often seen in people who have Parkinson's disease.[2][3]
The afferent sensory signals are transmitted by the trigeminal nerve to the brain stem; the efferent signals go to the orbicularis oculi muscle via the facial nerve, causing the muscle to reflexively contract, yielding blinking.
See also
References
- ^ Talley, Nicholas (2018). Clinical examination : a systematic guide to physical diagnosis. Chatswood, N.S.W: Elsevier Australia. p. 599. ISBN 978-0-7295-4259-3. OCLC 988941211.
- ^ Salloway, Stephen P. (2011-01-01). "Glabellar Reflex". In Kreutzer, Jeffrey S.; DeLuca, John; Caplan, Bruce (eds.). Encyclopedia of Clinical Neuropsychology. Springer New York. p. 1149. doi:10.1007/978-0-387-79948-3_1897. ISBN 9780387799476.
- ^ Vreeling, Fred W; Verhey, Frans R J; Houx, Peter J; Jolles, Jellemer (1993). "Primitive reflexes in Parkinson's disease". Journal of Neurology, Neurosurgery, and Psychiatry. 56 (12): 1323–1326. doi:10.1136/jnnp.56.12.1323. PMC 1015384. PMID 8270937.