from what I've experienced precognition and communication (whether after death or living) occur during sleep cycles, but only during a specific period of sleep cycle. I have nothing to prove this, it's just what I feel is going on.
The events that tend to come true are those that if I were to trace them back, they can be seen as already being in the midst of happening, such as worldly events, earthquakes, economical rise/fall, etc. What's interesting though is that a season or month, year, etc. can be found somewhere in the dream as well.
Communication during dream cycles seem to just be a matter of picking up mental or energetic signals, ESP, telepathy, etc. It could be the rest of our radio stations are closed during sleep with one particular channel wide open to recieve thought communication.
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Elleise
Clairvoyance Editor
Angel Therapy, Consultations & Courses