A latent state-trait analysis of interoceptive accuracy.

Interoceptive accuracy (IAc), that is, the ability to accurately perceive one's own bodily signals, is widely assumed to be a trait, although experimental manipulations such as stress may affect IAc. We used structural equation modeling to estimate the reliability of IAc, and the proportions of individual differences in IAc, explained by a trait and occasion-specific effects of situation and person-situation interactions. We assessed IAc in 59 healthy participants (40 women, M  = 23.4 years) on three consecutive measurement occasions, approximately 1 week apart, in a rest and poststress condition, using a heartbeat counting and a heartbeat discrimination task. The results showed fair temporal stability (intraclass correlation coefficients ≥ 0.38) and good reliability (Mdn = .63; range .49-.83) for both methods. While around 40% of the variance of a single IAc measurement could be explained by a trait, approximately 27% was accounted for by occasion-specific effects of situation and person-situation interaction. These results suggest that IAc measures are relatively consistent and that situations and person-situation interactions impact IAc as measured at a certain point in time. An aggregation across at least two measurements is recommended when using IAc as a trait variable.