Interoception—the ability to attend to internal bodily signals—is thought to support self-awareness, emotion regulation, and cognitive function, but empirical evidence for its neural basis is limited. In this study, 36 healthy adults performed the Heartbeat Counting Task while their brain activity was recorded with EEG. Source localization revealed that, compared to rest, the task increased alpha-frequency current density primarily in the right parahippocampal gyrus. Additionally, changes in beta-frequency activity in medial cortical structures, especially the cingulate gyrus, correlated with task performance. These findings suggest that EEG source localization can reveal neural correlates of interoceptive accuracy.
Electrophysiological recordings are commonly used to study the neural correlates of consciousness. Previous research is inconsistent as to whether awareness can be indexed with visual awareness negativity (VAN) at about 200 ms or if it occurs later. This preregistered study tested for VAN and whether stimulus size may account for inconsistent findings. Subjects viewed low-contrast Gabor patches in four visual quadrants; Gabor size (large and small) was varied and calibrated to each subject's threshold. Event-related potentials were derived from trials where subjects localized Gabors correctly, comparing trials with reported awareness versus no awareness. Bayesian analyses revealed very strong evidence for VAN for both sizes, but no evidence for or against an effect of stimulus size. The findings provide evidence for VAN as an early neural correlate of awareness.