Dr. Jack Feldman

It also has signals coming from the brainstem down, which are called efference.

But it's getting major signals from the lung, from the gut.

And this is going up into the brainstem.

So it's there.

There are very powerful receptors in the lung.

They're responding to the expansion and relaxation of the lung.

And so if you record from the vagus nerve, you'll see that there's a huge respiratory modulation due to the mechanical changes in the lung.

Now, why that is of interest is that for some forms of refractory depression, electrical stimulation of the vagus nerve can provide tremendous relief.

Why this is the case still remains to be determined, but it's clear that signals in the vagus nerve, at least artificial signals in the vagus nerve, can have a positive effect on reducing depression.

So it's not a leap to think that under normal circumstances that that rhythm coming in from the vagus nerve is playing a role in normal processing.

Okay, let me continue.

carbon dioxide and oxygen levels.

Now, under normal circumstances, your oxygen levels are fine.

And unless you go to altitude, they don't really change very much.

But your CO2 levels can change quite a bit with even a relatively small change in your overall breathing.

That's going to change your pH level.

I have a colleague, Alicia Moret, who is working with patients who are anxious.

And many of them hyperventilate.

And as a result of that hyperventilation, their carbon dioxide levels are low.

She has developed a therapeutic treatment where she trains these people to breathe slower to restore their CO2 levels back to normal.