High blood pressure responders show largest increase in heartbeat perception accuracy after post-learning stress...

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 min 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.