Imagine yourself looking at a cascading waterfall or listening to the song of a skylark. Physical time is flowing linearly forward, with no letup in the relentless passage from instant to instant. The stimuli that are reaching your sense organs are always changing. Many a new stimulus is over just as soon as it arrives.
But this is not how you experience it at the level of sensation. Rather, the present moment, the “now” of sensation, has a paradoxical dimension of temporal depth. Each instance of sensation is still there for you for a brief period after you create it, as if it happens for longer than it happens. Thus successive instances are co-present in consciousness. But this is not because the old is lasting into the time territory of the new; it is because each new instance lives on for a little while in its own time. You have co-presence of sensations without simultaneity.
— Humphrey, Nicholas. Soul Dust: The Magic of Consciousness. Princeton, New Jersey: Princeton University Press, 2011.
