I think you are conflating all brain function with intellect. That is not the case. Will and, for want of a better word, spiritthese are transcendent functions that go beyond logic and reason.
Unlearning slowly is a matter of self-calming of a person’s reactions/responses to specific stimuli. It takes time, even years; so some of the beneficial side effects are a growth of patience and self-encouragement to avoid or endure tough situations. The person wanting to change learns to shift gears mentally, not to treat every hard-on as a critical emergency demanding response. As time goes on, abstinence from the “undesired desires” becomes learned in place of the impulse to seek gratification.
Will is part of intellect and ‘spirit’ remains undefined.
Remember, the arrow goes both ways. If anyone can, over time, change physiological sexual responses from gay to straight, they are be able to go the opposite way. I don’t believe any amount of self-calming can make me respond to some guy’s hairy back. Not only would I never want to, but I don’t think it’s possible.
There’s a reason pedophiles are said to be incurable. If response is malleable, why aren’t pedophiles being cured?
As time goes on, abstinence from the undesired desires becomes learned in place of the impulse to seek gratification.
But gratification is. The attempt to eliminate gratification leads to the problems such as pedophilic ‘celibate’ clergy. Gratification is part of human nature which means there are consequences to its smothering.