One may argue that these findings are all obtained with stimuli that are presented de novo, using the classic stimulus-onset paradigms. In normal vision, things don’t suddenly appear out of nowhere. Or do they? We naturally make about three saccadic eye movements per second, and each time the eye lands on a “new” scene which is—from a retinotopic point of view—radically different from the previous one. In between, we are blind due to saccadic suppression. Moreover, little information seems to be transferred from one view to the next, although some (attended) neural representations seem to be remapped across saccades (see Bays & Husain 2007, for an overview of trans-saccadic memory and neural remapping). Such a remapping may allow for a more efficient saccade from one object to the next, when both were already present before the first saccade was made. The predictive coding framework seems to re-emerge in this context: objects that were present or attended on a first fixation form a sort of prior for the representation that is built during the second fixation (which may then arise more rapidly).
Melloni further claims that previous experience has different effects on what is perceived now depending on the temporal interval between prior and current experience. Bistable percepts show hysteresis or adaptation depending on these temporal intervals, or depending on whether the previous experience was conscious or not. But again, I fail to see how these findings support the idea that consciousness is stretched out over time instead of just happening now.[3]
So I appreciate the importance of the predictive coding framework. Previous experience plays a very important role in the conscious sensations we have, and the why and how of this is extremely important for fully understanding vision. But these contributions are unconscious. Consciousness happens now, and its neural correlates are likewise limited in time. Consciousness of the past we call memory.
Acknowledgements
This work was supported by an advanced investigator grant from the ERC.