Human Beings have an Autonomic Nervous System (ANS) that is actually comprised of three separate subsystems, the Parasympathetic Nervous System (PNS), the Sympathetic Nervous System (SNS) and the Enteric Nervous System (ENS). The enteric nervous system has been described as a "second brain," which communicates with the central nervous system (CNS) through the parasympathetic (e.g., … Continue reading Function of the Vagus Nerve