Augmentation of the auditory event related potentials of the brain during diastole.

Previous studies demonstrated that stimuli synchronized with systolic and diastolic phases of the pulse pressure wave enhanced the visual event related potentials (ERPs) of the brain. The present study extended these observations to the auditory ERP in passive and attentional conditions. Pure tones were synchronized with systolic and diastolic phases of the cephalic and palmar arteries. During one condition, subjects were paid a bonus for reporting accurately the number of times they heard a tone (attention condition) and in a second condition they listened passively (non-attend). Stimuli synchronized with the diastolic phase, reliably produced augmentation of the N1 component across all conditions. The N2 component was smaller in the right hemisphere of attentive subjects when stimulation was synchronized with diastole. These results were discussed in the context of the cognitive psychophysiology proposed by Picton and Hillyard (1974).