However, when the animal was exposed to novelty some ours before, the expression is still high during waking, it's decreased during slow wave sleep but then it's reinduced, it's increased again during REM sleep this is the first demonstration that there is a molecular day residue, not just an electrophysiological not just what happens at the membrane level with the potentials, but if you go inside the nucleus, there's a switch in the gene expression program so as to generate long term memories during REM sleep, but only when there's something new to learn, OK? 