[stubish]

Copyright law does not apply to imaginary reproductions, such as your imagination. Your question becomes more interesting if get someone to draw that scene from Blade Runner. At that point, it comes down to if a judge considers the derivative work transformative enough (for hand drawn sketch, it would be, except maybe if drawn by a savant). And in the Batman case, you might violate trademark law depending on what you did with image after you drew it, which is a whole other set of rules.

When was the last time you heard the original Happy Birthday song sung on TV? It is now generally avoided, because producers don't want to pay royalties to the copyright holders.

[Glyptodon]

We should assume that at some point we'll be able extract imaginary and remembered images and sequences from neural activity - I think very poor/crude versions exist already.