Event-related potentials, heart period, and brain-heart responses during a threat of shock oddball task: Replicability and 6-month-reliability

Abstract

In a previous study (Gerpheide et al., 2024), we observed that unpredictable threat modulated event-related potentials (N1 and P2, but not P3) and heart responses during an oddball task as well as the communication between brain and heart as measured with cardio-electroencephalographic covariance tracing (CECT). Individual differences in brain, heart, and brain-heart responses to threat may provide biological markers for threat-related personality traits and psychopathology. However, to serve as psychophysiological markers the observed phenomena need to be replicable and individual differences in these phenomena must be reliably assessed and be temporally stable. To address this issue, N = 60 participants of our previous study completed the same auditory oddball paradigm with threat of shock vs. safe contexts 6 months after the initial study. With regard to replicability, all experimental effects that were observed during the first time were also significant 6-months later. With regard to reliability, amplitudes of original ERP waveforms, evoked HP changes and one CECT component showed substantial split-half and test-retest correlations. Moreover, difference scores (threat minus safe) for the P2 and N1 also showed substantial split-half (.55 < r < .72) and test-retest correlations (.41 < r < .67) indicating that individual differences in brain responses to threat vs. safety can be reliably assessed and show moderate stability. Taken together, ERP, HP and CECT thus provide replicable and relatively reliable measures in the context of unpredictable threat and may be helpful for better understanding key mechanisms of and individual differences in threat processing.