Central and Peripheral Nervous Systems

Abstract

Abstract The nervous system comprises billions of nerve cells in the body. It is the organization of the nervous system that allows different functions to occur effortlessly. The nervous system is divided into two systems, the central and peripheral nervous systems, based on their location. The central nervous system is organized from the cerebrum to the spinal cord, with layers of communicating inputs throughout. The peripheral nervous system can either respond autonomously to sensory inputs from the body, or relay messages from the central nervous system. Cerebral blood flow and cerebral perfusion pressure are tightly autoregulated to stay consistent across a range of mean arterial pressures. The blood brain barrier is a layer of endothelium with tight junctions, excluding many peripherally circulating molecules. Lipophilic molecules penetrate this barrier better than hydrophilic compounds.