Right, in some of these attempts cues are learned before the participants fall asleep, so that they react to it while dreaming. One could argue that the distinc

Right, in some of these attempts cues are learned before the participants fall asleep, so that they react to it while dreaming. One could argue that the distinction is subtle, and La Berge could've found the results these groups are showing today, had he ran the experiment. Nonetheless, experimenter->dreamer communication during sleep as suggested in this paper is AFAIK indeed new.