From studies I've done I've found that chronic gaslighting can lead to multiple different forms of coping methods. The shutting off of (or repression) emotions being the main one. Primarily the feelings of emotion which from what I've read is the frontal lobe. The emotions are still generated by the limbic system though so they have a passive influence on thought patterns and actions. I'd guess that eventually through further manipulation and gaslighting the limbic system starts to lose its potency as well. I don't have any scientific articles though. Just theories and passive interest into the field. When your emotions are used against you often you tend to avoid them all together.