Nervous System Foundations 01 What Is The Nervous System

So what is the nervous system?

It's,

You know,

Pretty trendy these days to learn a lot about the nervous system,

Which as a huge neuro nerd is very promising to me.

I think it's really,

Really amazing that so many people are interested in learning about it.

And because it's so buzzy,

I just wanted to break it down to make it really simple to understand.

So here we go.

What is it?

The nervous system is a collection of structures that is made up of nerve cells or neurons,

Is what we would call them.

And we'll get into the physiology and specifics of how it works and how it all communicates in another video,

Because that'll be a little more complex.

So in this one,

All you need to know is that the nervous system is made up of nerve cells.

The primary structures within the nervous system are broken down into different categories,

And I'm going to walk you through it with this beautiful drawing that I've made.

So have a look here.

The nervous system at the top,

As you can see by my beautiful printing,

Is broken down into two parts.

So we have the central nervous system and the peripheral nervous system.

Cool.

Got it.

The central nervous system is made up of two primary structures,

The brain and the spinal cord.

And they're considered the central nervous system because they behave slightly differently and have different properties than the rest of the nervous system,

Which we call the peripheral nervous system over here.

So brain,

Spinal cord.

The brain is essentially grand central station of the nervous system.

Every message that comes in and every message that comes out is processed in grand central station in the brain.

And the brain is broken down into several different areas and has much more complex information beyond that.

However,

That's all you need to know.

Grand central station.

The spinal cord is the super highway that information travels on.

It's kind of like the freeway.

So connecting the peripheral nervous system to the brain is that central structure,

The spinal cord.

And that spinal cord is information going in and information coming out constantly up and down the spinal cord.

Moving over to our peripheral nervous system.

The peripheral nervous system is the rest of the nervous system that isn't in the brain or spinal cord.

So as you can see here,

We have it further broken down into the autonomic nervous system and the somatic nervous system.

You've probably heard the term fight or flight,

Rest and digest.

The autonomic nervous system is what governs this part of our nervous system.

So the autonomic nervous system is part of the peripheral nervous system,

Meaning it comes off of the spinal cord and has special branches,

Special types of nerves that are on alert at all times,

Keeping us safe.

And this part of the peripheral nervous system is exactly that,

That governs whether we are in fight,

Flight or freeze,

Which is what we would call our sympathetic nervous system.

And on the flip side of that,

The parasympathetic nervous system is what governs us to be in more of a rest,

Digest,

Calm state.

And we'll get into the specifics of the autonomic nervous system.

It's,

You know,

Much more information than that.

However,

Knowing that the autonomic nervous system is part of the peripheral nervous system is basic enough for our purposes today.

So moving on,

We have the somatic nervous system over in this corner here.

So the other portion of the peripheral nervous system that we focus on is the somatic nervous system.

The somatic nervous system is our communication with the outer world.

So the two main things that it does are sensory information inward and motor control or muscular control outward.

And so this is where we interface with our environment.

We'll get more specific about how nerve endings and receptors work as we move into,

You know,

Some more of the nitty gritty of it all.

However,

Understanding that our spinal nerves,

Which are one portion of the peripheral nervous system,

How they interface with the world is by sense,

Sensation,

Right?

And so if we touch something,

A nerve ending is going to pick that up.

It's going to travel on a spinal nerve and go to the spinal cord,

Now transferring over to the central nervous system.

That message is going to go up to the brain,

Grand central station.

It's going to process the information it just received and then decide what it wants to do about it.

So sometimes it does nothing.

Sometimes it says,

Hey,

What I just touched didn't feel so great.

Perhaps I will activate muscles via the spinal cord and then the spinal nerves to perhaps remove my hand from that sensation that didn't feel so great.

So the somatic nervous system is exactly that.

It's the part of the nervous system that is constantly communicating and interacting with,

You know,

Everything that we're touching,

Things that we're seeing or smelling,

Hearing,

Etc.

So within the somatic nervous system,

There are two further divisions.

And I mentioned spinal nerves.

Our spinal nerves are the nerves that come off of the spinal cord,

Meaning that any information that comes off of a spinal nerve must travel via the spinal cord up to the brain and vice versa.

There is another subset to the somatic nervous system called cranial nerves.

And cranial nerves behave just like spinal nerves,

Except they don't travel from the spinal cord.

So these are the nerves that come directly from the brain.

And for the most part,

Most part,

There are exceptions to this.

They perform actions that are largely on the head.

So things like vision,

Things like hearing and taste,

These are all governed by our cranial nerves.

And they also govern muscles of the head,

The neck,

The jaw.

And there's a lot of same concept.

You're getting inward sensation and outward activation,

But we're just skipping the spinal cord.

I won't make it more complicated than that.

However,

I hope that this has been helpful to understand the main overarching structures of the nervous system.

And I'll give you another little shot at this just to break it down now that we've gone over it.

So Overall,

We have the nervous system.

We have the central nervous system,

Which is broken down into the brain and spinal cord.

Over here,

We have the peripheral nervous system,

Which is broken down into our autonomic nervous system and our somatic nervous system.

Our autonomic nervous system is broken down into our sympathetic nervous system and our parasympathetic nervous system.

And then over here,

Back over to that somatic nervous system,

We have our cranial nerves and our spinal nerves.

I hope you've enjoyed this video,

My beautiful drawings that go with it.

And I will see you next time.

Thanks for watching.