When the heart and the brain meet: Brain-heart interactions in feature integration

Abstract

In contemporary Cognitive Neuroscience, increasing attention is devoted to brain-body interactions, as an expanding body of literature suggests that processing the external world may not emerge from the brain in isolation but rather from the coordinated contribution of multiple bodily systems. These interactions have been extensively studied in the context of interoception. However, evidence linking them to visual perception remains scarce. To address this gap, the present study reanalyses a previously published dataset from 25 participants to investigate heart-brain interactions during a visual feature integration task. Participants were required to integrate shape and colour features to identify a target while inhibiting distractor-related information. Cardiac and neural activity were simultaneously recorded, enabling the assessment of the heart rate (HR), heart evoked potentials (HEP), and, albeit seldom reported previously, heart evoked oscillations (HEO). Prestimulus HEP amplitude briefly differed between correctly and incorrectly integrated features. HEO analysis revealed alpha and low beta band modulations before target onset. These effects were absent when the analyses were aligned to external events and exceeded surrogate distributions obtained after disrupting heartbeat EEG alignment, indicating that they depended on cardiac timing rather than on spontaneous prestimulus EEG differences alone. These findings provide preliminary evidence that HEO dynamics are associated with successful perceptual integration and extend previous work on HEPs from stimulus detection to higher-level perceptual processes. More broadly, they suggest that heartbeat-locked neural activity may influence early brain states linked to perceptual outcomes, aligning with theoretical frameworks proposing an active role for bodily signals in perceptual processing.