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Which structures make up the central nervous system?

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Diagram of a human figure showing the full nervous system, including the brain, spinal cord, and branching peripheral nerves throughout the body, with labels for each part. — human nervous system The conduction of electrochemical stimuli from sensory receptors in the human nervous system occurs via organized groups of specialized cells, consisting largely of neurons, various neural support cells, and tracts of nerve fibers.

The central nervous system (CNS) is composed of two primary structures: the brain and the spinal cord.12

Both of these structures are derived from the embryonic neural tube and are centrally positioned along the midline axis of the body. To ensure their protection, the brain is encased within the skull (the neurocranium), while the spinal cord is housed within the vertebral canal, which is formed by successive vertebrae connected by dense ligaments.12

Additionally, both the brain and spinal cord are surrounded by protective membranes known as the meninges and are cushioned by cerebrospinal fluid, which circulates throughout the system. Functionally, the CNS serves as the primary center for receiving, processing, and coordinating information, playing a critical role in regulating both voluntary and involuntary movements, as well as supporting complex cognitive processes.123