The Distribution of Useful Frequencies in Polygraph Sensor Channels

Purpose: to help other polygraph researchers better understand the distribution of energy across diff erent frequencies in the standard six polygraph channels in common use.Th e channels shown will be pneumo, electrodermal (Axciton), cardio cuff pressure, movement sensor, and infrared plethesmo (Axciton). In all cases we use a zero phase high pass filter with a fourth order roll off . Unless otherwise noted, all frequency traces are kept with a constant gain to show their relative energy or strength content.