Heart rate and sustained attention during childhood: Age changes in anticipatory heart rate, primary bradycardia, and respiratory sinus arrhythmia

This study examined age changes in three aspects of heart rate responsivity elicited in an auditory oddball task; anticipatory heart rate change, primary bradycardia, and respiratory sinus arrhythmia. Three age groups (5-, 7-, and 9-year-old boys) were presented with series of target (15%) and standard (85%) tones. The results were consistent with the findings reported previously in the adult literature. Heart rate decreased in anticipation of the target tone. The morphology of anticipatory deceleration was somewhat different for the 5-year-olds compared to the older children. Stimuli presented during the early part of the cardiac cycle induced added deceleration, but this primary bradycardia did not differ between age groups. Respiratory sinus arrhythmia did not discriminate between age groups but was suppressed during the performance of the oddball task relative to base level. It was concluded that these three aspects of heart rate responsivity show developmental constancy rather than change.