The temporal advantage for reloading vs. uploading conscious representations decays over time

Abstract

In motion-induced blindness (MIB), a static target superimposed on a global moving pattern frequently disappears and reappears into consciousness. We previously reported an intriguing illusory temporal reversal whereby a new stimulus onset (e.g. a dot flash) presented during MIB triggers an early reappearance of the target, yet is systematically perceived as occurring after the target reappearance. This illusion implies that the unconscious target representation can be quickly reactivated, with a temporal advantage for its conscious reloading as compared to the conscious uploading of a newly presented visual stimulus. However, it remains unclear whether the temporal advantage for conscious representation reloading strengthens, decays, or remains constant over time after we lose the initial conscious access to the stimulus. To address this question, we examined the relation between the duration of MIB and the percentage of illusory temporal reversals, and we found a negative correlation between the two measures, both between and within observers. The results suggest that although the unconscious target representation retains a certain level of activation during MIB, the temporal advantage for reloading its preexisting representation into consciousness decays over time.

Keywords: illusory temporal reversal; motion-induced blindness (MIB); unconscious object representation; visual awareness.

Figure 1

(a) Actual sequence of events during a trial in the test session. The task was to indicate the disappearance and reappearance of the ring target as well as the perceived temporal order of the dot probe and ring target. After participants reported the onset of MIB, the dot probe was flashed inside the ring target at a particular time delay of either the first, second, or third quartile value of the MIB duration distribution obtained in the pretest session. (b) Perceived sequence of events during a trial when an illusory reversal of temporal order occurs. Although the onset of the dot probe is the event that brought the ring target back into awareness, participants usually reported that they saw the ring target before they saw the dot probe.

Figure 2

The group averaged histograms of MIB durations for the three different probe onset delay conditions in the pretest and test sessions. Before averaging, all participants’ MIB duration distributions were first aligned to the corresponding probe onset time (i.e. PreQ25, PreQ50, and PreQ75 indicated by the gray vertical lines), which is one of the quartiles computed from each participant’s MIB distribution in the pretest session. For all three conditions, the onset of the dot probe triggered an early reappearance of the ring target, as indicated by the significantly truncated distribution after probe onset.

Figure 3

Negative correlations across participants between the percentage of ring-first responses and the corresponding quartile value. In each of the probe onset delay condition, participants with longer quartile values show less illusory temporal reversals (as indicated by less ring-first responses), suggesting that the unconscious target representation decays over time in MIB and gradually loses its temporal advantage for conscious access. Note that the baselines refer to the expected percentages of ring-first responses that would occur due to a natural termination of MIB.