How do people get insights during dreams?

From: Nirmesh Joshi

Many a times i have heard people saying that in unconscious state of mind means in dreams they have observed that some formula, some idea,some slokas,some advise given in dream which is not possible for them when they are awake, so how it is possible? and we have heard that due to KARMA one is gifted with intelligence,intellectual power so does this differ when person is conscious or unconscious state