The mediumistic drawing is probably something very primal, basic, essential, probably far more natural than art itself.
Jan Švankmajer The sale of Heaven 2000
Automatic or mediumistic drawing is "passive" listening to the echo. It requires absolute release of the mind, similar to meditation. The deeper the release the more you feel it is not you who draws. The hand seems to detach from your will and does what it wants. In other words, it does what you can't control but what has an obvious but still incomprehensible meaning to us.
The mediumistic drawing feeds on the psychic world of spiritualism. That means the hand drawing medium is not controlled by its consciousness, but by the vast underground world of the dead, which often transcends cosmic boundaries.
Jan Švankmajer Roads of Salvation 2018