It would be easy to get theological on this subject, but it really doesn't help that much.
"Going into Emptiness" as a brain state (thanks for MRI's and experimental adapts) is the forebrain shutting down and the limbic brain lighting up. Heh, the doctors became VERY alarmed, because by the rules of neurology, as we understand them, she should have been comatose right then, or at the very least unable to speak. Yet, she was able to speak clearly and understand what was going on around her.
The best way to explain the reason a person can or would do something like that is through the example of math. When we process math with our forebrains, it's an exercize in symbolic manipulation. The symbol for "2" combined with the symbol "X" and another symbol "2" yields the results of the symbol "4". With limbic processes, you go onto Emptiness and touch the Platonic Reality of "2 X 2 = 4".
If you like reading biography, consider finding out more about the Indian math-wiz Ramanujan. He claimed that he knew the answers to complex mathematical problems because the Goddess Namagiri wrote the answers on his tongue. This is how his mind perceived the act of going into Emptiness. (Or, to remain more agnostic on the subject, Namagiri exists in Emptiness and brought Ramanujan into it to give him the answers).
