City Centre Chiropractic

Brisbane 3229 6993

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At City Centre Chiropractic, when we adjust your spine, we are stimulating a whole bunch of your sensory nerves, which in turn sends information to your brain where it determines an appropriate response - hopefully we can create enough change to make you feel better.  The cells involved in this process are quite complex so I thought I would jot down a few points about neurons and nerves,to help you understand how your body works.

The human body is made up of trillions of cells. Cells of the nervous system, called nerve cells or neurons, are specialized to carry "messages" through an electrochemical process. The human brain has approximately 100 billion neurons. Neurons come in many different shapes and sizes. Some of the smallest neurons have cell bodies that are only 4 microns wide. Some of the biggest neurons have cell bodies that are 100 microns wide. (Remember that 1 micron is equal to one thousandth of a millimeter!).

Neurons differ from other cells in the body because:

1. Neurons have specialized extensions called dendrites and axons. Dendrites bring information to the cell body and axons take information away from the cell body.

2. Neurons communicate with each other through an electrochemical process.

3. Neurons contain some specialized structures (for example, synapses) and chemicals (for example, neurotransmitters).


There are a few ways to classify neurons, one way is by the number of extensions that extend from the neuron's cell body:

Bipolar neurons have two processes extending from the cell body, Pseudounipolar cells have 2 axons rather than an axon and dendrite. One axon extends centrally toward the spinal cord, the other axon extends toward the skin or muscle.  Multipolar neurons have many processes that extend from the cell body. However, each neuron has only one axon.

Neurons can also be classified by the direction that they send information:

Sensory neurons: send information from sensory receptors (e.g., in skin, eyes, nose, tongue, ears) TOWARD the central nervous system, the brain .

Motor (or efferent) neurons: send information AWAY from the central nervous system to muscles or glands.

Interneurons: send information between sensory neurons and motor neurons. Most interneurons are located in the central nervous system.

Did you know?

Neurons are the oldest and longest cells in the body! You have many of the same neurons for your whole life. Although other cells die and are replaced, many neurons are never replaced when they die. In fact, you have fewer neurons when you are old compared to when you are young.

Neurons can be quite large – the longest axon in the body extends from the base of the spine to the big toe…..about 3 feet!

It has been said that if all the other body cells were somehow removed the network of fine nerves would be numerous  enough to enable you to easily recognize the individual concerned and to recognize every tissue layer in his or her body.

The adult human spinal cord weighs about 35 grams.

Although your brain can store virtually unlimited data, it weighs only about 1.5 kg.

The brain constitutes only 2% of the body weight, but it takes up to 20% of the blood from the heart (cardiac output), 25% of glucose utilization, as well as 20% of oxygen consumption.

There are no nerve endings inside the brain, so the brain itself can’t feel pain. You can cut open your brain and feel nothing (as long as you manage to do all this without touching the skull).

 Adapted from:

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