I go through phases where, when I sleep, I don't have any dreams (that I remember, at least). I sleep well and I wake up rested. Every few months I go through a week or two when I have nights full of incredibly vivid dreams and I wake up remembering at least five or six of them. Because of all these vivid dreams, I wake up feeling far less rested than I do when I don’t dream at all. Is there a particular reason for this? Does dreaming more at night mean your sleep is less restful?