In a recent review of some material I was doing research in Kashmir Shaivism, I came across a reference that seems to corroborate with some of the experiences that evocators refer to. Both the aspects of substantial spirit contact via vivid multi-sensory stimulation as well as the highly increased power of the manifestation of the operators intent.
The particular mental state referred to as vijnanakala pramatribhava is characterized by these phenomena that almost exactly correlate with reports of evocation to visible appearance.
Various signs referring to strong inner sounds, extreme joy, basically many inner senses stimulated. Also the state is characterized by the power of true speaking, where the yogi in this state finds that what he or she says comes to pass. Whether cursing or granting boons, or stating that such and such a thing will happen in a particular way, and then it does.
This is referred to as the third state of consciousness that follows after two others. Since it may be useful for others to corroborate with their own experiences I’ll briefly relate those here also.
The first state called sakala pramatribhava. This is a state of focused concentration where the yogi does not lose consciousness of the world around him. The senses are still active at this point, so one can hear others talking for example.
The second state called pralayakala pramatribhava. This is where the yogi sinks deep inside himself to the extent where he loses consciousness of what is happening around him, but also loses consciousness of the object of meditation. In this state it’s possible to enter into an early type of samadhi where breathing stops or slows down significantly.
These earlier stages, seem to correlate with EA’s description of the Theta/Gamma Synch, the dimming of sensory impression of the surrounding area, and the eventual position of reaching the Crossroads state. This combined with the statement of intent for the spirit matches very closely with the information I came across.
I thought this was a good reference that further substantiates EA’s methods, laying out another strong point of argument that is substantially irrefutable for anyone willing to do the research.
The text: Aspects of Kashmir Shaivism, Conversations with Swami Lakshmanjoo, Volume I, Chapter 10.