The heart shapes social pain: Effects of cardiac cycle across younger and older adults

Social pain is a subjective negative experience induced by social exclusion. Recent research revealed that social pain is modulated by interoception, and attenuated during cardiac systole (a phase characterized by increased arterial baroreceptor signals) than cardiac diastole. However, little is known about differences in social pain between cardiac cycle phases in older adults. To address this issue, this pre-registered study investigated differences in social pain between cardiac cycle phases across younger and older adults. Participants completed a Cyberball task using a computerized ball-tossing game with two other players. In the exclusion condition, the other players kept tossing the ball to each other, and the ball was thrown to the participant only during the first several tosses and not thereafter. Throws between the other players were defined as exclusion events. The timing of the exclusion events was manipulated, such that they were presented either at cardiac systole (R-wave peak, +300 ms) or diastole (R-wave peak, +550 ms). Replicating previous findings, older adults demonstrated lower levels across several measures of interoception, including heart rate variability (HRV) and self-reported body awareness. However, they showed attenuated social pain during cardiac systole than diastole as seen in younger adults. These results suggest that the mechanisms by which cardiac cycle phases modulate social pain are preserved across the adult lifespan, despite age-related declines in HRV and self-reported body awareness.