Melloni discusses some impressive experiments that show the crucial importance of prior information and expectation in shaping or simply altering conscious experience (and her example, figure 1, is enlightening and flattering at the same time). In all these cases, however, consciousness is portrayed as the outcome or result of an otherwise unconscious inferential process. The result may come earlier or later, as in the experiment on letter priming that Melloni describes, resulting in earlier (200ms) or later (300ms) electrophysiological correlates of conscious recognition depending on the presence or absence of appropriate priors. Further experiments are discussed, showing that neural correlates of consciousness may shift (neural) location, depending on expectation and priors. Yet still, the end result—consciousness—occurs at the end of a cascade of neural operations. Consciousness, in this account, may occur at variable moments and locations, but moments they are.
These results complement earlier findings that the latency of recurrent processing—and hence the emergence of a conscious sensation—may vary. Super et al. (2001) showed that degrading stimulus quality may increase the latency of recurrent signals to V1 in the monkey visual cortex (see figure 5c of Supèr et al. 2001), and that this affects the latency of behavioral responses of animals that are consciously reporting the presence or absence of the stimuli. Latency of recurrent signals may also vary spontaneously between trials, which correlates with the latency of memory-guided—but not reflexive—saccades to the targets that elicit these recurrent signals (Supèr et al. 2004). In humans, the latencies of electrophysiological correlates of recurrent processing also vary, either spontaneously or depending on stimulus properties (Jolij et al. 2011), or depending on the IQ of the subject (Jolij et al. 2007). Likewise, this has consequences for the latency of conscious sensations. The Jolij 2011 study, for example, found that variations in the latency of recurrent EEG signals co-vary with variations in subjective simultaneity of the stimuli evoking these signals.[2] These results invariably imply that consciousness arises at a particular moment in time. That moment may vary from stimulus to stimulus, from trial to trial, from person to person, from prior to prior. But nothing is flowing or stretched out over time.