Ok - This will be kind of a long Seth excerpt, but I just so impressed by (what I feel) are major similarities between the following ideas and the MBT model. I think this sheds a little light on the process whereby we experience this and other reality systems, and also ties into some of the responses already given here. -->
The probable realities connected with your own system are like the suburbs, say, surrounding a main city. If for simplicity's sake you think of other realities as different cities, then after you leave your own you would pass through the suburbs, then into the country, then after a time into other suburbs until you reached another metropolis. Here each metropolis would represent a conglomeration of consciousnesses operating within an overall general frequency of clearest focus, a high point of psychic communication and exquisite focus in the given kind of reality. Unless you are tuned in to those particular frequencies, however, you could not pick up that reality. You might instead perceive the equivalent of jumbled sound or meaningless static, or jigsaw images. You might simply realize that some kind of activity was there, but without being able to pinpoint it.
Now all consciousness, including your own, is highly mobile. While you focus your attention primarily in your own world, certain portions of your consciousness are always straying. When you are sleeping, then, your consciousness often ventures into other realities, usually in a wandering fashion without tuning itself in to any precise frequencies. Beneath many seemingly chaotic dreams there are often valid experiences in which your consciousness "lights" in another reality, without being attuned to it with the necessary precision that would allow for clear perception. The information cannot be sifted or used effectively and is translated into dream images, as your consciousness returns toward your own home station. Therefore, it has been difficult to achieve any kind of clear picture of such other realities.
Certain particular focuses then bring in different worlds, but unless your consciousness is tuned in with exquisite precision you will not be able to perceive dearly. You will instead pick up at best the ghost images, probabilities, and private data that are not officially recognized as part of the main reality's official structure of events.
Basically, consciousness is freewheeling. Such realities therefore always exist-in your own psyche-outside of your "home station, " and some portion of your own consciousness is always involved in them. Period. There are bleedthroughs, so to speak, in the form of unofficial perceptions that often occur, or "impossible" events that are seemingly beyond explanation. For now think of your own psyche, which is a consciousized identity, as a kind of "supernatural radio." All of the stations exist at once within the psyche. These do not come through with sound alone, but with all the living paraphernalia of the world. The "you" that you recognize is but one signal on one such station, tuned in to a certain frequency, experiencing that station's overall reality from your own viewpoint-one that is unique and like no other, and yet contributing to the whole life of the station.
(Smile:) The supernatural radio that is your entire psyche contains many such stations, however. These are all playing at the same time. It would be highly confusing in this analogy to experience or hear all of these at once, however, so different portions of the psyche tune in to different stations, concentrate upon them, and tune out the others for immediate practical purposes. Because these stations all operate within the same psyche or supernatural radio, the overall quality of the programs will have much to do with the nature of the psyche itself. Radios are wired and contain transformers and transistors. The overall reception is dependent upon the wiring and the inner workings of the radio-and (intently) those workings exist apart from the stations they are meant to pick up. In the same way, the "supernatural psyche" exists apart from the stations of consciousness that it contains. In this case indeed the psyche itself makes the radio, adding ever-new connections and stations
-Seth, Session 711