Sorry to be a bit pedantic, but circadian rhythm is "a natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours." I beli

Sorry to be a bit pedantic, but circadian rhythm is "a natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours." I believe you meant REM cycles, in your first sentence (which matches up to your next sentence).