High blood pressure responders show largest increase in heartbeat perception accuracy after post-learning stress following a cardiac interoceptive learning task

Mental disorders with physical symptoms, e.g. somatic symptom disorder, are characterized
by altered interoceptive accuracy (IAc), which can be explained by individual differences in
interoceptive learning (IL). We investigated if stress facilitates IL. Seventy-three healthy
participants performed a heartbeat counting task (HCT: T1) and a heartbeat perception training
(HBPT). After exposure to a socially-evaluated cold pressor stress test (SECPT; n=48) or a control
condition (n=25), two more HCTs were performed (T2: 30 minutes after SECPT; T3: 24 h later).
After the HBPT, all participants showed an increase in IAc. We separated the stress group into
high vs. low systolic blood pressures (SBP) responders (n=24 each), with high SBP responders
showing the largest IAc increases. Only SBP, but not cortisol responsiveness significantly
predicted IAc increase from T1 to T2. Our results indicate that post-learning autonomic stress
response facilitates IL, whereas the HPA axis response may be less important for this effect.