Dr. Charles Zuker

And that includes all the way from monitoring the frequency of heartbeats and the way that inspiration and aspirations in the breathing cycle operate to what happens when you ingest sugar and fat.

Let me give you an example.

So Pavlov, in his classical experiments in conditioning, you know, associative conditioning, he would...

take a bell, it will ring the bell every time it was going to feed the dog.

Eventually, the dog learned to associate the ringing of the bell with food coming.

The dog now, in the presence of the bell alone, will start to salivate.

And we will call that, you know, neurologically speaking, an anticipatory response.

Neurons in the brain that form that association now represent food is coming and they're sending a signal to motor neurons to go into your salivary glands to squeeze them so you release, you know, saliva because you know food is coming.

But what's even more remarkable is that those animals are also releasing insulin in response to a bell.

Somehow the brain created these associations and there are neurons in your brain now that no food is coming and send a signal somehow all the way down to your pancreas that now it says release insulin because sugar...

is coming down.

Now, the main highway that is communicating the state of the body with the brain is a specific bundle of nerves, which emerge from the vagal ganglia, the nodal ganglia.

And so it's the vagus nerve that is innervating the majority of the organs in your body.

It's monitoring their function, sending a signal to the brain,

and now the brain going back down and saying, this is going all right, do this, or this is not going so well, do that.

They all must be monitored.

I have no doubt that diseases that we abnormally associated with metabolism, physiology, and even immunity,

are likely to emerge as diseases, conditions, states of the brain.

I don't think obesity is a disease of metabolism.

I believe obesity is a disease of brain circuits.