Slow-paced breathing enhancing emotional control accompanied with the change of the ∼0.1 Hz heartbeat evoked EEG

Figures

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  Fig. 1. Experimental protocol. (A) Procedure for the emotional control regulation experiment. (B) Visual guidance for a single trial in the AA task. (C) Visual guidance for a single trial in the SPB task.

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  Fig. 2. Schematic representation of data analysis. (A) Procedure for HOP extraction. (B) Non-parametric tests of the cortical HOP in source space, including phase-based and marker-based permutation tests. (C) Comparisons between SPB and SB on the averaged HOP amplitude (across all subjects), and the phase distribution analysis of HOP across all HOP trials. (D) Analysis of the difference in actual respiratory rate and respiratory duration on HOP during the SPB task.

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  Fig. 3. Effects of SPB on emotional control ability and cardiac activity. (A) SPB improved emotional control ability, as indicated by the decreased congruency effect (CRCC- CRIC). Bar chart illustrating the 95 % confidence intervals around the mean of the dependent variable. SB: spontaneous breathing; SPB: Slow-paced breathing; CC: congruent condition; IC: incongruent condition. (B) The CR of the AA task across four conditions was analyzed using repeated measures analysis of variance followed by post-hoc pairwise comparisons (factor 1:in-task condition, CC vs. IC; factor 2: breathing condition, SPB vs. SB). (C) HRV power spectra of 37 subjects under SPB and SB conditions, showing an increase in the ∼0.1 Hz component of the LF (0.04–0.15 Hz; grey shaded area) during SPB. The purple area represents SPB, while the green area represents SB. (D-E) SPB significantly increased the ∼0.1 Hz HRV power and RMSSD. Each dot corresponds to one participant (*, p < 0.05, **, p < 0.01, ***, p < 0.001).

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  Fig. 4. Time-varying distribution of cortical HOP. (A) Cortical distribution of HOP with the trough of the ∼0.1 Hz heartbeat oscillations as onset, showing the 10 s time course of the HOP. The top row displays the sec averaged cortical HOP map, with the color bar indicating the absolute source amplitude. Areas without color fall below the minimum value threshold. The purple curve represents the ∼0.1 Hz heartbeat oscillations. The second row presents the p-maps after the phase-based permutation test of cortical HOP, with the color bar representing p-values and redder colors indicating smaller p-values. (B) Cortical distribution of HOP with the peak of the ∼0.1 Hz heartbeat oscillations as the onset.

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  Fig. 5. Spatiotemporal effects of SPB on HOP. (A) P-maps of cortical HOP are generated through a phase-based permutation test. The first row displays p maps for the SB condition, while the second row is for the SPB condition, with each p map averaged over seconds. The color bar represents p-values from the permutation test, with the redder reflecting lower p-values. In the SPB condition, significant regions are primarily concentrated in the parietal and right frontal lobes, highlighted by blue circles. (B) Comparison of HOP time series between SB and SPB conditions. Green waveforms represent the HOP time series in the SB condition, and purple waveforms represent the SPB condition. Shaded areas show ±1 SEM around the mean. The HOP time series corresponds to the ROI in the upper right corner. The x-axis represents time, and the y-axis indicates HOP amplitude. The gray area highlights the time windows with significantly higher HOP in SPB.

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  Fig. 6. Phase-specific distribution of HOP amplitudes. (A) Phase distribution of higher HOP trials around the peak of ∼0.1 Hz heartbeat oscillations in the right frontal lobe and right precentral gyrus. The 0 degree represents the trough of the ∼0.1 Hz heartbeat oscillations, 180 degrees for the peak. Green plots represent the phase distribution of higher HOP during SB, while purple plots represent SPB. Red lines indicate the mean phase direction for each plot. Statistical comparisons were conducted across all trials. For visualization purposes, only the top 30 % of the trial distributions with higher HOP amplitude were shown (20 bins). (B) Phase distribution of higher HOP trials around the trough of ∼0.1 Hz heartbeat oscillations, including right medial orbitofrontal and postcentral.

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  Fig. 7. Effect of respiratory rate and respiratory duration on HOP. (A) Scatter plot of respiratory rates. Light blue dots represent the respiratory rates of all subjects during SB, while green, black, and red dots indicate median, above-median, and below-median respiratory rates during SPB, respectively. The x-axis shows the subject number, and the y-axis represents the respiratory rate. (B) Lower respiratory rate subjects exhibited higher ∼0.1 Hz HRV power and improved emotional control ability compared to the higher respiratory rate group. Bar chart illustrating the 95 % confidence intervals around the mean of the dependent variable. (C) Effect of respiratory rate on HOP in superior frontal and rostral middle frontal cortices. Red waveforms represent the HOP time series in the below-median respiratory rate subjects, and purple waveforms represent the above-median respiratory rate subjects. Shaded areas show ±1 SEM around the mean. The HOP time series corresponds to the ROI in the upper right corner. The x-axis represents time, and the y-axis indicates HOP amplitude. Grey areas highlight significant time windows that survive after cluster-based permutations (*, p < 0.05). (D) Scatter…

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  Fig. 8. Directional connections between heart-brain interactions and emotional control ability. (A) HOP mediation diagram. Standardized regression coefficients for the relationship between ∼0.1 Hz HRV power and enhanced emotional control mediated by increased HOP neural response in the right superior frontal cortex. (B) The ∼0.1 Hz HRV power mediation diagram. The ‘a’ represents the effect of X on M, ‘b’ represents the effects of M on Y, and ‘c' represents the effect of X on Y (total effect). The proportions mediated (95 % confidence interval) are shown in each figure’s center (*, p < 0.05).