knee-jerk reaction. Fig. an automatic or reflex reaction; an immediate reaction made without examining causes or facts. With one of his typical knee-jerk reactions, he said no immediately, citing some moral argument that no one understood. See also: reaction.
What did you see when the patients head was rolled to the opposite side? In horizontal canal BPPV, you should have seen a direction change. When the horizontal nystagmus is geotropic, the BPPV is suspected to be canalithiasis, occurring on the side with the more intense nystagmus.
(ËhÉr ÉËzÉn tl, ËhÉr-) adj. 1. at right angles to the vertical; parallel to level ground. 2. flat or level: a horizontal position. 3. being in a prone or supine position; recumbent. 4. near, on, or parallel to the horizon. 5. measured or contained in a plane parallel to the horizon: a horizontal distance.