Multiple Sclerosis 101: Understanding the Nervous System

Last updated: July 2022

I have a theory that education leads to empowerment, and empowerment leads to people being good advocates for themselves and improved health overall. It can be difficult for healthcare providers to explain complicated diseases, such as multiple sclerosis, during office visits. There is so much to cover in such a short time, that often education is minimized or cut out altogether in order to make sure that we have plenty of time to address other issues during the office visit.

Researching everything I could about MS after my diagnosis

My first reaction to being diagnosed with MS was to go on an information binge and learn everything I possibly could. I had the advantage of already being a neurosurgical nurse and of having nearly a decade of training and education in human biology, anatomy, physiology, and pathology. However, the average person diagnosed with a serious neurological disease doesn’t have a background in neurology. I can’t imagine how difficult it would be to try to understand it all on your own, without any prior knowledge. After all, even some of the nurses and doctors I know recoil at the thought of neurology because it is a difficult topic to learn and master.

Learning neurology concepts to better understand MS

However, I have confidence that you all will be naturals since you live these concepts every single day. Firsthand experience is always the best way to learn! So, I want to attempt to teach you the major concepts of neurology, with the hope that you will get a deeper understanding of what MS is and how it affects you. If you’ve ever had a symptom and wondered “what in the world was that?”, then this is for you!

What exactly is the nervous system and what does it do?

First, the basics: the nervous system is divided into two parts, the central nervous system (CNS), and the peripheral nervous system (PNS). It is easiest to picture the nervous system as a tree. The CNS is the tree’s roots and truck, consisting of the brain and the spinal cord. The PNS is the tree’s branches, consisting of nerves that travel to our organs, glands, muscles, and skin.
Overall, the main job of the nervous system is to organize and keep all the cells in your body on task. It acts as the body’s drill sergeant and leader. Since the brain can’t scoop up a megaphone and yell marching orders, it communicates with its army of cells via electrical and chemical signals. These signals travel from the nervous system through nerves and down to cells until the command is carried out.

The nervous system never sleeps

The nervous system never sleeps and is constantly gathering information and reacting to it at an astonishing speed. For example, when your stomach is empty it sends a signal that your brain recognizes as hunger, and you become aware that you need to eat something. Some signals are automatically detected and responded to, without you even having to think about them. These are known as reflexes.

What is a reflex?

An example would be when you touch a hot stove the sensation travels up your nerves and into your spinal cord. This triggers an instant response, and your muscles quickly jerk your hand away. Your brain simultaneously processes the incident which makes you say, “Ouch, that was hot!”.

Every task our body does, consciously or unconsciously, must travel through the nervous system in order to be completed. This information is usually communicated so quickly that we don’t even realize how complicated a process it is.

Sensory nerves and motor nerves

The PNS is made up of sensory nerves and motor nerves. Sensory nerves do exactly what they are named for! They sense what is going on in the body by gathering information from our skin, muscles, bones, joints, and organs such as the bladder, stomach, and lungs. They then take this information and send it to the CNS for processing and further commands. Once commands are issued by the CNS, it is the job of the motor nerves to carry out these orders. This is the basic principle behind all of our bodies’ voluntary functions, and it is also where communication breaks down and problems start to occur in people with MS.

Explaining MS bladder dysfunction

Bladder dysfunction is a perfect example. Sensory nerves sometimes “over-sense” and signal our brain that our bladder is full long before it really is, and the result is an overactive bladder that constantly gives you the urge to urinate. In others, the nerves “under-sense” and fail to alert your brain that your bladder is full and can result in leaking of urine or incontinence. Motor nerves can affect the bladder too. Since the bladder is a muscle, and we depend on muscles to hold in urine, muscle weakness can cause incontinence. Additionally, leg weakness can make it difficult to make it to the bathroom.

And that’s really the basics. Not so bad right? Now, if you are feeling brave, let’s move onto Part 2: Everything You Need to Know About Nerves.

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This article represents the opinions, thoughts, and experiences of the author; none of this content has been paid for by any advertiser. The team does not recommend or endorse any products or treatments discussed herein. Learn more about how we maintain editorial integrity here.

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