Can one incubate on a specific idea in one's sleep?
This study found that REM sleep "enhances the integration of unassociated information for creative problem solving", and to an extent that surpasses the benefits of "quiet rest and non-REM sleep". try a google scholar search for 'psychology sleep  incubation '. 

Interestingly, the experiment that yielded the first discovery of a neurotransmitter was famously claimed to have been conceived of during a dream and was conducted during the middle of that same night. The scientist, Otto Lowel, had failed to successfully document the same dream nights prior.