Background The autonomic nervous system (ANS) constitutes a fundamental regulatory mechanism for physiological homeostasis, comprising two primary branches: the sympathetic nervous system (SNS), which mediates “fight-or-flight” responses, and the parasympathetic nervous system (PNS), responsible for “rest-and-digest” functions (Wang et al., 2025). The ANS exerts multilevel control over cardiovascular, metabolic, and immune functions via pathways such as the neuro-cardiac axis.
