It's all coming together now,Ringo Starr wrote and sung Octopus's Garden and octopus have rings! It naturally follows that they also dream which has been studied with interesting results. When an octopus sleeps they change color and twitch,the color change is significant because it follows patterns of their waking color changes,for example if they see a crab (dinner) they get lighter colored and once they catch the crab they turn darker to blend in with the ocean bottom while they eat. I'm betting they do dream,why wouldn't they? We know how intelligent they are,using tools and figuring out fairly complex problems so dreaming doesn't seem beyond their pay grade.