36 A κ coefficient for interclinician agreement could not be calculated because data about how each clinician scored each patient was not included. The glabellar tap reflex is elicited through repeated stimuli to the glabellar region of the forehead, inducing concomitant blinking with each tap. Friedman JH, Abrantes AM Int J Neurosci 2013 Jun;123(6):417-9. Successive tapping of the glabella eventually leads to habituation with blinking being suppressed. Alex Rajput, Ali H. Rajput, in Handbook of Clinical Neurology, 2007. The glabellar reflex is a poor measure of Parkinson motor severity. The glabellar reflex is a primitive reflex. Parkinson's Disease and Related Disorders, Part II. Myerson's sign also called as glabellar tap sign is a medical condition where a patient is unable to resist blinking when tapped on the glabella, the area above the nose and between the eyebrows. Epub 2013 Feb 11 doi: 10.3109/00207454.2012.762917. Interclinician reliability in eliciting the glabella tap sign was found to be 88% among patients with intracranial disease and 100% in controls. It is elicited by tapping the forehead between the eyebrows and nose and observing that the eyes blink.