Single-trial electroencephalogram predicts cardiac acceleration: a time-lagged P-correlation approach for studying neurovisceral connectivity.

Cortical efferences to the heart are important for cardiovascular health, psychopathology, emotion regulation and other dimensions of human functioning. Although researchers have already begun to outline the underlying neuroanatomy, the timing of neurovisceral communication in humans is difficult to study non-invasively. A possible coupling between the brain and the heart can be observed following feedback stimuli, which have been shown to evoke both, early (i.e. <500 ms) signatures in the electroencephalogram (EEG) and changes in the chronotropy of subsequent heart beats. Because standard approaches may be insufficient to study how these responses are related, we suggest a method termed "Cardio-Electroencephalographic Covariance Tracing" (CECT), which is based on time-lagged P-correlations (i.e., correlations within individuals) between single-trial EEG magnitudes and heart period changes. When CECT was applied to data from n=31 individuals who performed a gambling task, central midline EEG magnitudes from 280 to 340 ms after feedback reliably P-correlated with cardiac acceleration 2 to 5 s thereafter. In addition positive vs. negative feedback lead to enhanced event related potential amplitudes from 200 to 280 ms and to relative cardiac acceleration from 1 to 3.5 s after feedback presentation. The results imply that neurogenic cardiac modulations begin to be affected 200 to 400 ms after stimulus presentation and demonstrate the utility of CECTs for future investigations.