Thanks Kora , 
That’s really interesting ! Even nail biting has the same origin( cortex) ? how do we relate it to cortex ? Can you help plz , is there any clue to relate it ? Or it’s a general rule for compulsions ?

2. Feeling here you mean the beliefs that come with the conflict ? Because feelings in devaluation are always nearly the same ( I can’t do that, I can’t …) ، so here we work on his belief and on what he feels he can’t do and we try to reverse this ! Right ? 
Like in EVe’s case it was a belief that lead us to the original conflict and the persistence as you mentioned , did I get it right ?