Nervous System Foundations 05 What Is The Limbic System

Today's video,

We're going to chat about the limbic system.

So the limbic system is a collection of structures in the brain that are responsible for a certain set of actions in the body.

So the limbic system is made up of officially four structures,

The hippocampus,

The hypothalamus,

The amygdala,

And the thalamus.

What does it do?

The limbic system is responsible for four main things in the body,

And we have an acronym for them.

That acronym is HOME.

H-O-M-E.

H standing for homeostasis,

O standing for olfaction,

Which is a smell,

M standing for memory,

And E for emotion.

Let's break those down.

H,

Homeostasis.

Homeostasis is a technical word that means equilibrium or balance.

And so the limbic system,

What it does is based on the information that comes into it,

It will relay that information out and activate certain parts of the body to keep it in check,

To keep it in balance,

In equilibrium.

What does that mean?

Things like temperature regulation are a big part of homeostasis.

Things like activating our autonomic and our fight or flight system,

If something needs to be brought into check,

Or activating our parasympathetic division of our autonomic nervous system,

If something needs to be brought into check.

So the homeostatic mechanism of the limbic system is something that is always trying to bring the body back into balance.

And so that can mean many different things,

But that is the overarching definition of homeostasis.

O,

Olfaction,

Is the O in home.

Olfaction,

Like I said,

Is a smell.

I'm not entirely sure how it managed to get lumped into the limbic system,

But it is actually super,

Super interesting that it's in here.

And I'm going to circle back to that later in the video because it's kind of more of a fun fact than anything.

However,

Olfaction or smell is grouped into the function of the limbic system.

M,

Memory.

Memories are consolidated from short-term to long-term memory in the limbic system.

So the limbic system is responsible for helping to transmute our short-term memory into long-term memory.

Typically,

Our short-term memories happen kind of on a short-term circuit,

And unless they're super important,

They don't get transmuted into long-term memory.

So the limbic system has a role in deciding what's important enough to turn it into a long-term memory.

Now,

Typically,

These long-term memories are things that are important for keeping us safe.

So,

Unfortunately,

The big word trauma tends to get stored in and amongst the limbic system.

But other things,

You know,

Really happy memories,

Really important things.

The limbic system is responsible for storing memory long-term.

And the last letter of home is E,

Emotion.

So the limbic system has a large role in regulating our emotions and also deciding,

If an emotion is big enough,

What to do about it in the body.

So,

For example,

Fear.

If we have a threat,

Something that we're really fearful of,

The limbic system will signal to our autonomic nervous system to perhaps kick the sympathetic nervous system into high drive so that we can do something about this fear that we're seeing.

So emotions are a big part of what the limbic system is doing.

Oftentimes,

Those emotions are tied into the memories that it's storing.

I told you I'd circle back to smell,

Olfaction.

It's super interesting.

And the purpose of smell being linked into this,

You know,

Emotion,

Memory,

Homeostasis piece isn't entirely clear in the literature,

But I think it's really cool because smell is often really tied to memory.

It's really tied to emotion.

And I'm sure lots of people can relate to having a smell bring a really,

Really strong memory to the forefront,

Often a really emotional memory.

Super,

Super common for that to happen.

An example,

I recently was having a shower somewhere that wasn't at my home,

And the face wash that happened to be in the shower was one that I used while I was on a clinical placement in India several years ago.

Hadn't seen this face wash in forever.

And all of a sudden I go and I wash my face,

And I was like,

Holy smokes,

I'm right back into this environment where I was,

You know,

Showering in India using this particular face wash.

And it was so strong,

And it had such a nostalgia,

Joyful,

And yet like,

You know,

Very,

Very specific emotion that came with it.

And it was so strong.

So,

You know,

Perhaps the purpose is just to help us recall memories that are really important.

Speculation,

But who knows?

Anyway,

Limbic system.

Remember that acronym,

H-O-M-E,

Homeostasis,

Memory,

And emotion.

Hope that's helpful for you.

Enjoy.