The nervous system is a complex network of specialized structures (brain, spinal cord and nerves) whose mission is to control and regulate the functioning of the various organs and systems, coordinating their interrelation and the relationship of the organism with the external environment. It is organized to detect changes in the internal and external environment, evaluate this information and respond by causing changes in muscles or glands.
The nervous system is divided into two major subsystems: 1) the central nervous system (CNS) composed of the brain and spinal cord; and 2) the peripheral nervous system (PNS), which includes all nervous tissues located outside the central nervous system.
The CNS consists of the brain and the spinal cord. The encephalon is the part of the central nervous system contained in the skull and which comprises the cerebrum, the cerebellum, and the brainstem. The spinal cord is the part of the central nervous system located inside the vertebral canal and connects to the brain through the occipital foramen of the skull.
The CNS (brain and spinal cord) receives, integrates, and correlates different types of sensory information. In addition, the CNS is also the source of our thoughts, emotions, and memories. After integrating the information, through motor functions that travel through nerves of the PNS, it executes an appropriate response. The peripheral nervous system is made up of nerves that connect the brain and spinal cord to other parts of the body.
Nerves originating in the brain are called cranial nerves, and those originating in the spinal cord are called spinal or spinal nerves. Ganglia are small clusters of nerve tissue located in the PNS, which contain neuronal bodies and are associated with cranial nerves or spinal nerves. Nerves are bundles of peripheral nerve fibers that form centripetal information pathways (from sensory receptors to the CNS) and centrifugal pathways (from the CNS to effector organs).
I invite everyone to read Matias’ post with the topic of the day.