Perhaps it's analogous to CPUs? Perhaps it's better to power down your brain when you're not really using it rather than keeping it running hot at full frequenc

Perhaps it's analogous to CPUs? Perhaps it's better to power down your brain when you're not really using it rather than keeping it running hot at full frequency? The idle mind being the devils workshop and all... Perhaps (and again speculating) it allows currently active pathways to cool down, allowing different ones to activate. This is especially useful if you're trying to solve a difficult problem and seem to be going in circles along the same line of thought. Your inability to break out of the line of thought might at times be more neurological than cognitive.