[Evaluation of changes in pulse rate caused by stimuli (author's transl)].

Short acoustical stimuli induce a biphasic reaction in pulse rate. After an initial increase in frequency, pulse rate decreases below the value calculated before stimulation. This decrease is followed by a slow increase towards the baseline value. As described by other authors the maximum occurs at the 4th heart beat after onset of stimuli. It could be pointed out that the occurrence of the maximum is related to the pulse rate measured before the stimuli. The higher this rate, the "later" the maximum occurs if it is expressed in beats after stimulation. A new mode of evaluation which is independent of pulse rate pointed out that the time between stimulus and maximum is constant. It is proposed to use the evaluation described here in order to allow a most exact location of the extreme values. For experiments with very small variability of pulse rate the evaluation used till now will be sufficient, but only if the mean pulse rate and it's standard deviation before stimulation is mentioned.