The rishis looked closer and detected between each of these states a gap that acts like a pivot as one reality turns into another.
For example, just before falling asleep, the mind gradually leaves the waking state, withdrawing the senses, shutting out the waking world, but at the junction point before the mind actually falls asleep, a brief gap is opened, identical to the one that flashes by between each thought: it is like a little window into the field that is beyond either wakefulness or sleep.
This realization opened the possibility for leaving behind the usual boundaries of the five senses by diving through the gap.
Adapted from Quantum Healing: Exploring the Frontiers of Mind/Body Medicine, by Deepak Chopra (Bantam Books, 1990).