"What this exercise does:
In order to advance in psychic power, we must train our minds. When we are in a trance state, our brain waves slow down considerably. There are two sides to the brain- the left logical/intellectual masculine side and the right creative/intuitive feminine side. The right side is the seat of the subconscious. This is the area of the mind that is open to suggestion and programming and the seat of our astral power. When the left side of our brain is active in thinking, the right side cannot be accessed. Trance states shut off the left side so we can access and program the right side (subconscious).
It takes training to be able to induce a deep trance state. Deep trance states are not always necessary, but for specific workings, they are very important. Once we train our minds to go deeper and deeper into a trance, this becomes easier and easier and takes less and less time as we become adept. The mind is like a muscle and for most people, this exercise will be an introduction to a part of the mind that has never even been accessed before."
Source:
https://satanisgod.org/www.angelfire.com/empire/serpentis666/Trance.html