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.
â¢ The trigger position control may be located in the horizontal control section of your oscilloscope. It actually represents the horizontal position of the trigger in the waveform record. Horizontal trigger position control is only available on digital oscilloscopes. â¢ Varying the horizontal trigger position allows you to capture what a signal did before a trigger event (called pretrigger viewing).