node of Ranvier

Axons coated in insulating myelin conduct impulses faster than non-myelinated ones, partly because instead of just triggering one channel at a time in a chain reaction, a current can effectively leap from one gap in the myelin to the next.

These little gaps are the delightfully named nodes of Ranvier, and this kind of propagation is known as saltatory conduction, from the Latin word for leaping.

What happens when an action potential hits the end of its axon and is ready to do more than leap and jump all the way to another neuron? That, you will find out next time.

Today, you learned how your body is kind of like a big bag of batteries, and how ion channels in your neurons regulate this electrochemistry to create an action potential from resting state to depolarization to repolarization and a brief bout of hyperpolarization.

Yeah, creating an insulated section called an internode.

The bare gaps between these Schwann cells are the nodes of Ranvier, which allow the electrical signal to jump rapidly down the nerve.

Now, the reason this distinction matters clinically is that certain devastating diseases are highly specific to which type of myelinator is being attacked.

Yes.

It'll be a 40-yarder just inside the right hatch.

Ranvier, a right-footed kicker from Lexington, Kentucky.

Snap, set, Ranvier's kick on the way.

Good!

We worried about transfer portal special teams players, or are we just going to sit back until the big game's on the line? Mike Keith on the call.

Kick on the way.

Good.

Ranvier from 40 and now 43.

Danny's tactic seems to be just shouting.

He looks at Ranvier.

Yeah, well, I've written

Donald Trump, but okay.

He looks at Ranvier and the look he gives her is kind of like, why has she gone to all this effort? he looks like jay from the in-betweeners here when he's looking at her so

their topic is that christmas parties should be banned yeah

yeah

There are these little bits of exposed neuron along the axon, which have the sweetest names in this whole episode.

They're called the Nodes of Ranvier, which seems like an excellent working title for the eighth Harry Potter novel.

Harry

Potter and the Nodes of Ranvier.

Anyway, these nodes allow signals to hop from node to node, which lets the signal travel down a nerve

faster.

spots where there's insulation and spots where there aren't.

Now, the spots where there are no insulation, those are called the nodes of Ranvier.

That's where the actual ion transport is happening.

Into and out of the

Now why is that important? You can have faster charging, right? For the same amount of voltage, you need less ions.

That's always good.

And the signal travels a lot faster because of what we just said, right? And between these nodes of Ranvier, that's where the signal is traveling.

This mechanism is called saltatory conduction, where it goes from one node of Ranvier to the next node of Ranvier.