What's the difference between lucid dreaming and day dreaming? After all, a lucid dreamer knows what they are dreaming and that they are dreaming, so wouldn't that mean they are awake, just day dreaming?
Rebecca says: When a person lucid dreams, his body is asleep. When a person day dreams, his body is awake. That's the main physiological difference - which we know for a fact because we can scientifically measure things like:
There are other marked differences between the sleeping body and the waking body, explained in the article Why Do We Sleep? These will help you differentiate between the bodily states during lucidity and day dreaming.
But what about the mental experience? Again, lucid dreams and day dreams are very different, although these differences are harder to measure. Because they are both internally generated, reporting of these states is a subjective task. I'll give you my personal view of the differences, which I think most lucid dreamers would roughly agree with:
While day dreams are fun (research shows we day dream for 70-120 minutes every day) they are really just waking thoughts. We slip in and out of day dreams, visualizing our hopes and fears, reflecting on the past, future and fantasy. We maintain awareness of the outside world, to some degree, and can stop and re-start the fantasy if our attention is directed back to reality. Day dreams are fairly intangible, so when you day dream of running across the sand, the sensation is not really there; it's only imagined.
In lucid dreams, the fact that you are asleep and switched off from the real world means you are fully immersed in the dream world - literally seeing, hearing and touching your surroundings in a way that can vividly mimic reality. Your brain perceives the lucid dream world as vividly as if it were waking reality and you are fully tuned in to the experience. The dreamscape is largely self-generating (even when you consciously manipulate parts of it) and allows for illogical and unexpected creations to appear from the unconscious mind...