WAVE-FORM RELIABILITY OF THE PHASE RELATED EXTERNAL SUCTION BARORECEPTOR MANIPULATION METHOD

The phase related external suction (PRES) method of controlled carotid baroreceptor manipulation (a neck cuff with cardiac cycle timed press ure variations) has been used to investigate not only the human barore flex, but extrahomeostatic effects of baroreceptor activity (such as t he modulation of cortical activity, peripheral reflexes, and pain) as well. The present study provides quantitative within subject test-rete st reliability estimates of PRES effects on 6-s trial-length heart rat e waveforms. Mean within subject test-retest reliability for each aver aged heart rate response waveform was 0.77 for the baroreceptor stimul ation (systolic negative/diastolic positive cuff pressure) condition, 0.56 for the control condition (diastolic negative/systolic positive c uff pressure), and 0.69 for the difference between conditions. The imp ortance of analyzing time-intensity dynamics, rather than merely the m ean or maximum effect of any treatment variable is emphasized, and rec ommended for investigations of a wide variety of short duration, induc ed physiological time series processes.