One way to approach an understanding of this is from classic definition.
Historically, psychic abilities have been referred to as "Gifts of the Spirit" and not "Gifts of the Brain."
If it were all that easy to develop, then we would all take Telepathy 101 in High School and never have to use the telephone again; as well as Astral
Projection 101 and never have to pay to see a movie on the silver screen again. *L*
The sporadic nature of psychic abilities also points to the source being from outside the brain.
When we increase our psychic ability, what we are really doing is increasing our receptivity to telepathic messages received from Spirit in a myriad
of ways.
Most scientists are of the Dialectical Materialistic mindset. This means that they do not believe or are even open to believing in the soul, life
after death, the ability for consciousness to exist independently of a physical body and so forth.
So their analyses and conclusions are all slanted to reflect that prejudice.
In my many years of experience as a Spiritual Medium and Intuitive, I have come to know that all dreams are channeled from Spirit. Try telling that to
a traditional (Freudian) psychologist! *L*