Task-Dependent Heart-Brain Interactions Regulate Human Self-Awareness

Heart-brain interaction is the basis of self-awareness, a fundamental function to identify and distinguish us from others. However, how self-awareness is modulated by heart-brain interaction and whether this modulation is governed by task-induced internal states remains unclear. Using own-, celebrity-, and stranger-faces, human subjects' internal states (self-related and non-self-related) were induced by two different tasks: Own-Face and Celebrity-Face Recognition, respectively. Results showed that heart-brain interactions, indexed by pre-stimulus heartbeat-evoked potential, not only predicted subsequent subjects' self-recognition but also moderated the relationship between self-recognition and stimulus-driven sensory differences among external stimuli. Intriguingly, both this prediction and modulation were strongly task-dependent, showing in the Own-Face Recognition task but not in the Celebrity-Face Recognition task. Together, our results reveal for the first time adaptive heart-brain interactive self-awareness processing, placing a necessary constraint, namely, the task-induced internal state, on our understanding of how heart-brain interactions, or, more generally, body-brain interactions, regulate human self-awareness.