I'm aware of a few concepts, primarily from dream research, which indicate that dreams feature or integrate observed objects from the past several days into dream content.
For example, seeing a bike commercial can make a person dream of riding a bike; finding a molten piece of chocolate in one's pocket can make one dream of something brown and sticky. The colloquial term for this phenomenon is "day residue", invented by Freud.
Anecdotal evidence from my own life makes me question if something similar happens in the waking state. Do events from the past few days "prime" the brain to create new ideas based on those events?
Have there been studies that demonstrated that exposing a person to emotionally neutral objects causes them to come up with ideas related to those objects in the next few days? For example, is seeing art supplies more likely people to start an art project?