Recommended book : Shamans Among Us: Schizophrenia, Shamanism and the Evolutionary Origins of Religion Kindle Edition by Joseph Polimeni

Shamans Among Us is a thought-provoking essay on the idea that the
psychology of people who we today diagnose with schizophrenia is akin
to that of shamans in ancestral societies. Joseph Polimeni’s scholarly
book challenges several traditional concepts of both evolutionary
biology and medicine. I strongly recommend it to all those who dare to
think outside the box.”
– Martin Brüne, MD, author of Textbook of Evolutionary
Psychiatry: The Origins of Psychopathology

“What an aptly named book. Joseph Polimeni raises the interesting
notion that present-day schizophrenics are, in a real sense, descendants
of latter-day shamans— evolutionary selectees who served the
important societal function of communication with the supernatural.”
– David Koulack, PhD, author of To Catch a Dream:
Explorations of Dreaming

“As with other evolutionary theories, it casts a new light on matters
which were previously confusing and even inexplicable.”
– John Price, DM, MRCP, MRCPsych, DPM, co-author of Evolutionary
Psychiatry: A New Beginning and Prophets, Cults and Madness

From the Foreword (written by John Price):
This book is about man’s contact with the supernatural, and about the
people who make that contact, and how, if their contact does not go well,
they run the risk of being labelled as mad. The author, as an atheist,
analyses this process according to the latest knowledge of anthropology
and psychiatry.

Contact with the supernatural has at least three advantages for a group
of human beings, and these advantages may be described as morals,
divination and morale. There is little doubt that a group with a good
moral code functions well, and better than groups lacking a moral code.
If the code has the backing of the supernatural, it is more likely to be
followed by the group members; and if violation of the moral code is
punishable by supernatural forces rather than by other group members,
then so much better for the peace of the group.

Joseph Polimeni’s book makes a case for the shaman as a facilitator of
group processes and an agent of cohesion for the group. It may seem odd
that I am strongly recommending this book when I co-authored Prophets,
Cults and Madness with Anthony Stevens (Duckworth, 2000) in which we
made a case for the medico-religious practitioner being an agent of group
splitting, as the prophet proclaimed a new world order which made him
and his followers unacceptable to the group, as a result of which they
went off to a “promised land.” Is the medico-religious practitioner an
agent of homeostasis or an agent of change? It seems likely that he is
both. While the group is growing in size he is an agent of homeostasis,
but when the group gets to a certain size, he uses the same talents which
made him a shaman to become a prophet of a New Religious Movement
and so split the group. Like an amoeba, the same genetic material which
makes the group cohere changes function when it is time to split, and then
it organises meiosis and enables the amoeba to divide into two. Rapid
group splitting is important in evolution because it favours selection at
the group level rather than the individual level, enables the members of
the group to put the group interest before their own private interests, and
so makes the group more effective in its competition with other groups
(Price 2010). The idea of selection at the level of the group as well as
at the level of the individual and the gene has been out of fashion for
half a century, but is coming back into mainstream biology as a result of
arguments made by David Sloan Wilson and Edward O. Wilson (Wilson
1997,Wilson and Sober 1994,Wilson 2012). The human race is eusocial,
like ants and termites and some bees and wasps, and this has enabled it
to be almost as successful in conquering the earth as the eusocial insects.

Personal Note : The history of enlightenment dates back to thousands and thousands  of years of enlightening traditions in the past, and is similar to the rise of christianity, islam, judaism, freemasonry and so on and so forth, both esoterically and exoterically in nature. Shamanic people for decades have been pointed out as weirdo's without any evolutionary task in the West, but these views are changing, fortunately. The so called mentally ill and hypersensitives of today might, in a way, become the shamans, prophets, healers, visionaries, artists, writers, doctors, psychologists and / or psychics of tomorrow. How they will co-opt their gifts is a great challenge for the future.?Will they take an ordinary job in psychology or healing, or remain in a kind of counterculture and do their work overthere? It's very hopeful that the evolutionary purpose of altered states of consciousness and spiritual crises in the early ages might lead to a great future, once the community starts to understand what is going on. All might benefit from understanding of these facts. This might be an important task for the healthcare professionals and those involved in government policy on these subjects.

https://www.amazon.com/Shamans-Among-Schizophrenia-Shamanism-Evolutionary-ebook/dp/B00AZZ9FEM