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How are the brain and spinal cord protected inside the body?

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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 brain and spinal cord, which make up the central nervous system, are protected by a combination of bony structures, specialized membranes, and fluid cushioning.12

Bony Protection

The Brain: It is encased within the neurocranium, a bony vault often referred to as the skull, which provides a rigid, protective box for the brain tissue.13
The Spinal Cord: It is housed within the vertebral column, a series of connected vertebrae that form a protective canal.12

Membranes and Fluid

Meninges: Both the brain and spinal cord are enveloped by three protective membranes known as the meninges: the dura mater, the arachnoid, and the pia mater.14
Cerebrospinal Fluid (CSF): The central nervous system floats in cerebrospinal fluid, a clear, colorless liquid. This fluid acts as a mechanical barrier, cushioning the brain and spinal cord against shock and distributing the impact of physical trauma. It also helps maintain constant pressure within the cranium and transports metabolic waste away from nervous tissue.125