Human Heart Rate Conditioning Research Articles

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

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.

Conditioned heart rate deceleration under different dimensions of respiratory control.

ABSTRACTBoth accelerative and decelerative cardiac responses have been observed in studies on human heart rate conditioning. An interpretation of the contradictory responses regarded as conditioned seems to remain equivocal. Experiments generally have used shock or loud sound as the US, so that effects of respiratory and pressor reflexes on heart rate appeared to be implicated in the conditioning process.In the present experiment, the period following a simple non‐aversive signal‐detection task established a heart rate deceleration as the UR. During this period, subjects of three experimental groups controlled part of their respiratory cycle for 20 seconds. Respiratory control was either sustained inhalation, sustained exhalation or maintained shallow resting cycle, while control subjects exercised no respiratory restraint. The non‐aversive stimulation excluded excessive heart rate acceleration and permitted a CS to coincide with onset of relaxation in the postdecision period. Only in experimental subjects was a significant conditional deceleration of heart rate found. Conditional deceleration occurred in addition to a gradual drop in heart rate level during the experiment. When respiratory activity was not controlled, a biphasic response of heart rate was observed.

Minimal and maximal sensory intake and exercise as unconditioned stimuli in human heart-rate conditioning.

Minimal and maximal sensory intake and exercise as unconditioned stimuli in human heart-rate conditioning.