Making sense of what you sense: Disentangling interoceptive awareness, sensibility and accuracy

Garfinkel and Critchley (2013) recently proposed a three level model of interoception. Only few studies, however, have empirically tested this theoretical model thus far. The present study aimed at investigating (1) the central assumptions of this model, i.e. that Accuracy, Sensibility and Awareness are distinguishable facets of interoception and that Interoceptive Accuracy is the basic level of interoception, and (2) whether cardiovascular activation (as indexed by heart rate) is differentially related to the three facets of interoception. Analyses were conducted on a total sample of N=159 healthy participants (118 female [74.2%]; mean age = 23.9 years, SD = 3.3, range = 19-45) who performed either the heartbeat tracking task, the heartbeat discrimination task or both. The results suggest that Accuracy, Sensibility and Awareness are empirically distinct facets of interoception, showing no correlation when based on heartbeat tracking, but moderate correlations when based on heartbeat discrimination. The assumption that Interoceptive Accuracy is the basic level of interoception could only be partially confirmed. Instead, we conclude that the level of objective physiological states should be considered as the most basic level of interoceptive signal processing.