Heartbeat-Evoked Potentials as a Neural Marker of Meditative Depth

Meditation is suggested to enhance psychological well-being through sustained cultivation of interoceptive attention and emotion regulation, yet objective neurophysiological markers of meditative depth remain inconsistent and largely focused on the central nervous system, overlooking interoceptive mechanisms. Heartbeat-evoked potentials (HEPs), cortical responses to cardiac signals, offer a psychophysiological index of interoceptive awareness and attentional states. This study investigated whether HEPs systematically track self-reported meditation depth in experienced Vipassana practitioners, a tradition emphasizing the coupling of sustained bodily attention with non-reactivity.Thirty experienced Vipassana meditators completed two sessions of 35-minute silent meditation with simultaneous ECG and 64-channel scalp EEG recordings. Self-reported meditation depth was continuously assessed via real-time button presses on an ordinal scale (1-5). HEPs were extracted (−200 to 800ms relative to R-peak) and analyzed using ANOVAs and cluster-based permutation testing across levels of meditative depth. Mixed linear models examined associations between HEP amplitude range (high vs. low depth) and post-session psychological outcomes.Frontal and central HEPs reliably tracked meditation depth across both grouped (high 4,5 vs. low 1,2) and graded (1-5) analyses, demonstrating particularly pronounced effect sizes in the latter (e.g., Channel C3: p<0.001, f²=5.55; FDR-corrected). Greater intra-session HEP amplitude range correlated with reduced mood disturbance (p<0.001), decreased fatigue (p<0.001), increased vigor (p<0.001), and enhanced decentering (p<0.001; all FDR-corrected). Notably, HEP amplitude did not covary with traditional meditation tracking metrics like frontal-midline theta power.HEPs provide a novel, ecologically valid, and inherently personalized neural index of meditative depth, linking interoception with contemplative state changes. We propose that sustained HEP enhancements, reflecting heightened cardiac influence over cortical processing, may underlie meditation's broad therapeutic efficacy, given interoceptive disruption is a fundamental pathway to psychological disturbance.