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.
anisotropic. 1. having unlike properties in different directions. 2. doubly refracting, or having a double polarizing power. 3. in cardiac physiology, having nonuniform conduction; used to describe the nonuniform characteristics of the myocardium in the direction perpendicular to the conduction direction of a fiber. See also isotropic.