The problem is....they’re already used brains. We don’t know the changes in the brain since birth. What makes the brain change....obviously repeated stimulation plays a role
And unless you take a purely religious point-of-view, we don't know the state of the brain at birth.
I think it is generally accepted that many things can go wrong during the nine month gestation period of human development. Some birth defects take place during development in the womb and we are far from knowing how such might affect the brain.