Polyvagal Theory: Current Status, Clinical Applications, and Future Directions.

Polyvagal Theory proposes an evolutionarily informed neurophysiological framework for understanding how the autonomic nervous system supports social engagement, emotional resilience, and adaptive physiological responses. At its core, the theory emphasizes a hierarchical organization of autonomic states mediated by the vagus nerve, highlighting the unique role of the ventral vagal complex in facilitating social behavior and physiological flexibility through mechanisms such as neuroception, co-regulation, and dissolution. This paper reviews the empirical foundations of Polyvagal Theory, addresses methodological critiques - particularly regarding anatomical specificity and respiratory sinus arrhythmia (RSA) - and consolidates recent advances in autonomic measurement. Furthermore, it explores wide-ranging clinical implications across diverse conditions including trauma, chronic pain, autism, developmental disorders, and mood disorders. Finally, the paper advocates for applying a "science of safety" in clinical practice, education, and public health, offering future directions for research, clinical practice, and the systemic design of institutions that support physiological safety at scale.