I've readed McKenna, Robert Anton Wilson, Antero Alli, etc. Even studied Zen and vaious kind of meditation. And know what you mean.
But keep in mind that all that knowledge is somewhat buried, there are no modern "shamans" readily available, and if they exist, how would we differentiate them from charlatans?.
A person with this kind of "disorders" has a wrong map for reality, and i don't know if it's possible to self cure.
On the other hand all this kind of theories are not so mainstream and you will get massively downvoted for expressing your point of view on the matter.
On my very humble opinion, this so called disorders are problems with symbols assosiations, combined with very sensitive human beings. And where modern science tries to get the individual to adapt to the environment, older techniques tried to build a new map for reality, using the unique talents that every person has, and reordering the symbols on the mind.
Some similarities to this kind of work can be found in NLP (Bandler) and the work of Alejandro Jodorowsky.
Maybe shamanism is not the preferred theme in this forum, bu come on guys, shamans where the first hackers!
- Sorry if there are errors, i'm in a hurry and english is not my first language.