Last night I dreamed that I had a tip of the tongue experience. Tip of the tongue states are situations where you forget some piece of information, but have a strong sense that you actually know it. Often the information comes to you later in the absence of any outside reminder, strong evidence that the information was there all along.
In my dream, I could not recall the name of a university administrator I was meeting with. I experienced it just like a real TOT state. On waking, I not only remembered the dream, but I also had no problem recalling the administrator’s name. The TOT experience was completely confined to my dream.
This reminds me a bit of the phenomenon of state dependent memory, where a person’s physiological state serves as a memory cue. For example, some people will learn a fact well drunk, forget it when sober, but recall it again when inebriated. This was a central plot point in Chaplain’s film, City Lights.