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How convincing is current evidence for unconscious processing? Recently, a major criticism suggested that this evidence might be fully explained by a mere statistical phenomenon: regression to the mean (RttM). Since excluding participants based on an awareness assessment is a common practice in such studies, this post-hoc data selection might evoke RttM and lead to false effects that are driven by aware participants wrongfully classified as unaware. Here, we examined this criticism using both simulations and data from 15 studies probing unconscious processing (43 effects overall). In line with the original criticism, we confirmed that the reliability of awareness measures in the field is concerningly low. Yet using simulations we showed that reliability measures might be unsuitable for estimating error in awareness measures. Furthermore, we examined three proposed ways to assess whether an effect is genuine or reflects RttM; all suffered from substantial limitations, such as a lack of power or an unjustified linearity assumption. Accordingly, we suggest a new nonparametric solution, which enjoys high sensitivity and relatively high power. Together, this work emphasizes the need to account for the contribution of measurement error to effects of unconscious processing. It further suggests a way to meet the important challenge posed by RttM, in an attempt to establish a reliable and robust corpus of knowledge in studying unconscious processing.

Extensive research has shown that objects that are salient or match our task goals are most likely to capture our attention. But are we at the mercy of the constant changes occurring in our environment, and automatically move our attention to the ever-changing location with the highest priority? Or do we wait for clues that the appropriate moment has arrived to deploy our attention? We addressed this hitherto neglected issue in three experiments. Using a spatial-cuing paradigm, we examined whether attention is deployed as soon as a salient change occurs (the cue), or only when the context signaling that attention should be deployed appears (the search display). The cue matched the target color and was expected to enjoy high attentional priority. We used two separate response compatibility manipulations, one pertaining to the cue, in the cuing display, and the other to the cued distractor, in the search display. Neutral conditions allowed us to disentangle the respective effects of these manipulations. Participants deployed their attention in the search display when they could rely on contextual information, and in the cue display when such information was absent. These findings challenge the traditional interpretation of spatial-cuing effects. They are discussed within the Priority Accumulation Framework (PAF) that we confront to other attention models.

Understanding how consciousness arises from neural activity remains one of the biggest challenges for neuroscience. Numerous theories have been proposed in recent years, each gaining independent empirical support. Currently, there is no comprehensive, quantitative and theory-neutral overview of the field that enables an evaluation of how theoretical frameworks interact with empirical research. We provide a bird's eye view on studies that interpreted their findings in light of at least one of four leading neuroscientific theories of consciousness (N=412 experiments), asking how methodological choices of the researchers might affect the final conclusions. We found that supporting a specific theory can be predicted solely from methodological choices, irrespective of findings. Furthermore, most studies interpret their findings post-hoc, rather than a-priori testing critical predictions of the theories. Our results highlight challenges for the field and provide researchers with a unique, open-access website to further analyze trends in the neuroscience of consciousness.

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Extensive research has shown that objects that are salient or match our task goals are most likely to capture attention. But are we at the mercy of the constant changes occurring in our environment, and automatically move our attention to the ever-changing location with the highest priority? Or do we wait for clues that the appropriate moment has arrived to deploy our attention? We addressed this hitherto neglected issue in three experiments. Using a spatial-cueing paradigm, we examined whether attention is deployed as soon as a salient change occurs (the cue), or only when the context signaling that attention should be deployed appears (the search display). The cue matched the target color and was therefore expected to enjoy high attentional priority. We used two separate response compatibility manipulations, one pertaining to the cue, in the cueing display, and the other to the cued distractor, in the search display. Neutral conditions allowed us to disentangle the respective effects of these manipulations. Our results support the hypothesis that attention does not occur until the search-relevant context appears. These findings challenge the traditional interpretation of spatial-cueing effects. They are discussed within the Priority Accumulation Framework (PAF) that we confront to other attention models.

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A wave of criticisms and replication failures is currently challenging claims about the scope of unconscious perception and cognition. Such failures to find unconscious processing effects at the population level may reflect the absence of individual-level effects, or alternatively, the averaging out of individual-level effects with opposing signs. Importantly, only the first suggests that consciousness may be necessary for the tested process to take place. To arbitrate between these two possibilities, we tested previously collected data where unconscious processing effects were not found (26 effects from 470 participants), using four Bayesian and frequentist tests that are robust to individual differences in effect signs. By and large, we found no reliable evidence for unconscious effects being masked by individual differences. In contrast, when we examined 136 non-significant effects from other domains, a novel non-parametric sign consistency test did reveal effects that were hidden by opposing individual results, though as we show, some of them might be driven by design-related factors. Taken together, four analysis approaches provide strong evidence for the restricted nature of unconscious processing effects not only across participants, but also across different trials within individuals. We provide analysis code and best-practice recommendations for testing for non-directional effects.