by Nicole Murray, L.Ac.

Since this week’s feature article is about Multiple Sclerosis, a disease of the central nervous system, we wanted to take the opportunity to do an introduction to how the nervous system works.

The nervous system is the body’s control center-all your thoughts and movements are controlled here.

Nerve Cells

The way messages are sent between the body and the brain is via nerve cells called neurons. A nerve impulse (electrical signal) travels across a neuron to connect to another neuron via a tiny gap (called a synapse). This causes the release of neurotransmitters, or chemicals that relay the nerve signal to the next neuron.

The nervous system is divided into two networks, the central nervous system and the peripheral nervous system.

Central Nervous System

The central nervous system (CNS) is the hub of the nervous system, made up of the network of nerves in the brain and spinal cord. The brain and spinal cord are so critical to our survival and function that they are protected by the skull, thevertebral canal, and connective tissue called the meninges. Cerebrospinal fluid surrounds the brain and spinal cord to protect them from trauma and help deliver nutrients to the brain.

The brain processes and interprets information sent from the spinal cord.

It also receives information from and sends information to the peripheral nervous system (more on that system below).

The Brain

The brain is the control center of the body. Weighing just three pounds, the brain interprets senses, controls behavior and body movement, and is the seat of intellect, language and memory. It controls ‘subconscious’ functions like breathing, digestion, and swallowing. The primary functional unit is a cell called the neuron. “All sensations, movements, thoughts, memories, and feelings are the result of signals that pass through neurons.” (NIH). If you want to learn more about the workings of the brain, see this NIH fact sheet.

The Spinal Cord

The spinal cord is the link between the brain and the body. It is a cylindrical shaped bundle of nerve fibers connected to the brain, that runs down the center of the spinal column from the neck to the lower back.

Nerves from the spinal cord transmit information from your organs and from environmental stimulation to the brain. They also send information from the brain to other areas of the body.

Peripheral Nervous System

MedicineNet has a succinct summary of the Peripheral Nervous System (PNS). They write that the PNS is “the portion of the nervous system that is outside the brain and spinal cord…The nerves in the PNS connect the central nervous system (CNS) to sensory organs, such as the eye and ear, and to other organs of the body, muscles, blood vessels, and glands. The peripheral nerves include the 12 cranial nerves, the spinal nerves and roots, and the autonomic nerves. The autonomic nerves are concerned with automatic functions of the body, specifically with the regulation of the heart muscle, the tiny muscles that line the walls of blood vessels, and glands.”

The Nervous System and Acupuncture

Understanding the nervous system is critical to our work. Beyond the obvious reason that the CNS and PNS control every function of the body, we treat numerous disorders and diseases of the nervous system, including MS.

The Johns Hopkins Health Library has an excellent summary of nervous system disorders, as follows:

Vascular disorders, such as stroke, transient ischemic attack (TIA), subarachnoid hemorrhage, subdural hemorrhage and hematoma, and extradural hemorrhage
Infections, such as meningitis, encephalitis, polio, and epidural abscess
Structural disorders, such as brain or spinal cord injury, Bell’s palsy, cervical spondylosis, carpal tunnel syndrome, brain or spinal cord tumors, peripheral neuropathy, and Guillain-Barré syndrome
Functional disorders, such as headache, epilepsy, dizziness, and neuralgia
Degeneration, such as Parkinson’s disease, multiple sclerosis, amyotrophic lateral sclerosis (ALS), Huntington’s chorea, and Alzheimer’s disease