Look, it's like this (I bin lookin up notes).

Ego happens in the prefrontal cortex of the brain. It has to call upon info from many other parts to present a context (which includes details of the situation plus risks associated with various outcomes taken from past experience if you have it (inc what the limbic has to offer) all brought into working memory in the pre-frontal. The orbitofrontal cortex warns of socially embarrassing actions. (I think some of that comes from the anterior cingulate cortex but that's a vague marginal note I made.)

On that basis your response is decided. Your behaviour and reaction to it are fed back to the areas the info originated from, modulating what’s there.

So it looks like you're in trouble at any level if your frontal lobe is shut down. You can't stop it working. Unless I'm wildly out that's the anatomy of it.
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