Hemodynamic changes as a function of classical aversive conditioning in human subjects.

Abstract

ABSTRACTEleven subjects underwent a discriminative classical aversive conditioning paradigm while heart rate, stroke index, and hence cardiac index were continuously monitored. Ten out of 11 subjects showed heart rate decreases to the conditioned stimulus at the time of shock onset. This decrease in rate did not change other hemodynamic parameters. The hemodynamic response to the unconditioned stimulus was an increase in heart rate and cardiac index even though stroke index decreased. These results suggest that the conditioned heart rate changes in human heart rate conditioning are too small to alter other hemodynamic variables.