Elizabeth Weise at USA Today put it succinctly in her lede: "Researchers know that sleep deprivation makes people and animals less functional. Now a team of researchers in Wisconsin and Italy has found that in rats kept awake past their bed times, their brains begin to turn themselves off, neuron by neuron, though the rat is still awake."
So, in rats at least, individual neurons (oddly floating in a void in the artist...