Nerves

I want to know the physiology of nervousness.

I want to know the biologic process that occurs when I think of something that I am anticipating with trepidation and it feels like someone reached into my gut and started clutching my stomach.

What causes that? What synapse exists between the mind and the stomach that relays the message "She's having anxiety. SQUEEZE!"

I'll be back tomorrow to let you know how things go.