SLAP UPSIDE THE HEAD

I occasionally hear the expression ‘(s)he should be slapped upside the head’. It is used when someone exhibits a lack of judgment. I read recently that moral decisions are made in the area of the brain behind the right ear. Could it be that people exercise better judgment when a slap to the head gets blood flowing to that part of the brain? What about the expression ‘their conscience has been seared’? In light of recent studies focused on this area of the brain behind the right ear and ancient colloquial expressions like the above, I presume these brain muscles can experience atrophy from lack of use, or benefit from better blood flow.