Because it doesn't exist and won't be found on any brain scans - ever - anywhere.
It came out of the post Freudian psychoanalytical circular world of the protected class of self appointed intellectuals who traded reality in for words.
It places your thinking process onto a foundation of quicksand where anything and everything can be justified and always ends up with you being a weak victim of circumstance with no will.
They tried to mainstream that lack of integrity parading as psychoanalysis of the subconscious in the mid century era. They were laughed at and ridiculed so hard they had to lay low and hide out in the world of art galleries that psychoanalysed modern art into a pseudo fake acceptability. These were the truly stupid ones that claimed their visual art had to have wordy explanations accompany them because if you didn't have their education, you couldn't understand that visual art which was always the artist's subconscious.
Up until 40 years ago every medical professorial knew for a fact that autism was caused by the mother's subconscious rejection of the child and that ulcers were caused by stress.Today they believe that buildings are phallic symbols put there to oppress women, but men do that subconsciously. They said that in the 1950s and in the 1970's. Men hate women "subconsciously" you see, so men have to kneel to beg forgiveness and get better.
Psychology is a religion of superstition and control belonging to jews and communists