The PNS contains neurons that junction with the CNS and have long axons that extend to all parts of the body. Unlike the CNS, the PNS is not protected by the vertebral column and skull, or by the blood–brain barrier, which leaves it more exposed to toxins and mechanical injuries. The PNS acts as a relay, transmitting information between the CNS and the rest of the body. The reason why patients are not simply given dopamine is that dopamine itself is not able to cross the blood brain barrier. A related example would be the manufacture of L-Dopa, a man-made version of the neurotransmitter dopamine which is used as treatment for Alzheimer’s disease. It does however allow the transfer of beneficial molecules such as amino acids and glucose into the CNS. As its name suggests, the blood brain brain barrier prevents the transfer of non-lipid soluble molecules, which may include toxic molecules. The Blood Brain Barrierīetween the brain and its blood supply is the blood brain barrier. The CNS acts as the control centre, using neurons to send and receive information to and from muscles, glands, organs and others systems in the body primarily through the Peripheral Nervous System. Both are made of soft delicate tissue protected by the skull and spinal vertebrae.

The CNS consists of the brain and the spinal cord. The nervous system is separated in two classes: the central and peripheral nervous systems.ĭivisions of the Nervous System Credit: Cenveo CC BY 3.0 US Central Nervous System (CNS) Electrochemical signals connect the circuitry of the body and the brain, allowing for bidirectional signaling.

Much of the executive activity occurs in the brain, while the spinal cord mostly acts as an information highway to connect the brain to many cells throughout the body. The human nervous system is an extensive network of specialized cells that allow us to perceive, understand and act on the world around us.

Noah ringer 2020