(Imagination) is one of the characteristics that set us apart from animals. We barely understand how knowledge is stored in the brain ... can we explain imagination?
Anyone who has ever spent more than a few minutes with a cat knows that humans are not the only creatures with imagination.
I had a cat years ago that would spontaneously attack an otherwise empty spot on the wall, then bolt from the room as if its tail was on fire.
I have no doubt that our language skills and knack for abstract thought gives us a different sort of imagination than is experienced by various animals - however, I can't fathom a means by which this claim could be tested definitively.