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.
The subtropics refers to the zones immediately north and south of the tropic zone. The term can be used loosely to mean a range of latitudes between 23.5 and approximately 40 degrees. These areas typically have hot summers-- even hotter than tropical climates.