“A deeper point is that since a gandhabba does not have a physical body and a brain, citta can just flow “without control”.
So the brain helps the mind rest: since the brain slows down the processing of sense input, the mind can fall back to the bhavanga state in between the times the brain sends signals to it. Also, in deep sleep the mind can rest in its bhavanga state.
In the gadhabba state, there is probably no chance to be in the bhavanga state, and no such thing as “sleep”?
On the other hand, the gandhabba must still retain the gati of the human who died. If the human had the gati of listening to Dhamma then the gandhabba may seek out opportunities for listening to desana.
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