Morten Overgaard

To study whether the distinction between introspective and non-introspective states of mind is an empirical reality or merely a conceptual distinction, we measured event-related potentials elicited in introspective and non-introspective instruction conditions while the observers were trying to detect the presence of a masked stimulus. The ERPs indicated measurable differences related to introspection in both preconscious and conscious processes. Our data support the hypothesis that introspective states empirically differ from non-introspective states

In recent years increasing attention has been given to systematic comparison of theories of consciousness. Laudable practical projects have emerged in this regard, such as adversarial collaboration and the development of databases lending themselves to comparisons of empirical support for theories. In addition to the practical advances, theoretical advances have been made, such as a list of issues a theory of consciousness must address. We propose adding the issue of the ontogenetic emergence (O-emergence) of consciousness to the list of issues we use to evaluate theories of consciousness. O-emergence concerns how and when consciousness emerges ontogenetically in human beings. The underlying assumption is that there exists a point in the development of a human individual before which that individual is not and cannot be conscious. This assumption, in turn, depends on a widely shared assumption of cognitive neuroscience, which is that consciousness somehow depends on — or derives from — brain activity. In this paper, we lay out the O-emergence criterion and investigate whether it can be accounted for within the Global Neuronal Workspace theory, the Self-Organizing Meta-representational Account, and the Reorganization of Elementary Functions framework.

The contrasts between so-called objective and subjective measures of consciousness have been a dominating topic of discussion for decades. The debate has classically been dominated by two positions – that subjective measures may be completely or partially reduced to objective measures, and, alternatively that they must exist in parallel. I argue that many problems relate to subjective reports as they can be imprecise and vulnerable to a number of potential confounding factors. However, I also argue that despite the fact that subjective reports are fallible, all objective measures are derived from subjective measures, and, thus, will never under normal circumstances be more correct. I propose that the best and possibly only realistic way forward is a specific version of a “middle ground”: to attempt to improve subjective reports in a collaboration with objective research methods.

In this Letter to the Editor, we seize the opportunity to respond to the recent comments by Anzulewicz and Wierzchoń, and further clarify and extend the scope of our original paper. We re‐emphasize that conscious experiences come in degrees, and that there are several factors that determine this degree. Endorsing the suggestions of Anzulewicz and Wierzchoń, we discuss that besides low‐level attentional mechanisms, high‐level attentional and non‐attentional mechanisms might also modulate the quality of conscious experiences.

In this paper we argue that awareness comes in degrees, and we propose a novel multi-factor account that spans both subjective experiences and perceptual representations. At the subjective level, we argue that conscious experiences can be degraded by being fragmented, less salient, too generic, or flash-like. At the representational level, we identify corresponding features of perceptual representations—their availability for working memory, intensity, precision, and stability—and argue that the mechanisms that affect these features are what ultimately modulate the degree of awareness. We conclude the paper by demonstrating why the original interpretations of certain empirical findings that apparently pose problems for our account are, in fact, flawed.

Drawing on neuroscientific research and metacognitive theory, this ground-breaking volume examines the theoretical implications that are elicited when neural correlates of consciousness are identified. The relationship between consciousness and the brain has concerned philosophers for centuries, yet a tacit assumption in much empirically-minded consciousness research seems to be that if we can only develop a map of correlations, no further questions remain to be asked. Beyond Neural Correlates of Consciousness starts where others stop, by asking what these correlations may tell us about the nature of consciousness. The book contains chapters considering the upshots of finding the neural correlates of consciousness in light of the most prominent contemporary theories in the field. This illuminates the theoretical consequences of succeeding in the quest for the neural correlates of consciousness from the perspective of global workspace theory, higher-order thought theory, local recurrency theory, and REFCON models, in addition to considering how this quest is shaped by different conscious phenomena, such as dreaming, altered states of consciousness and different levels of consciousness. This insightful text features sophisticated theories that goes beyond correlational inferences and neural mapping, and will be of interest to students and researchers of consciousness, particularly those interested in interpreting neural correlates.

A number of recent publications have argued that a scientific approach to consciousness needs a rigorous approach to first-person data collection. As mainstream experimental psychology has long abandoned such introspective or phenomenological method, there is at present no generally agreed upon method for first-person data collection in experimental consciousness studies. There are, however, a number of recent articles that all claim to provide a unique contribution to such a methodology. This article reviews these suggestions and extracts their core features. It is argued that the suggested methods are generally overlapping and compatible, and a number of concrete methods that easily are applied to experimental studies are put forward.

Comparison of behavioural measures of consciousness has attracted much attention recently. In a recent article, Szczepanowski et al. conclude that confidence ratings predict accuracy better than both the perceptual awareness scale and post-decision wagering when using stimuli with emotional content . Although we find the study interesting, we disagree with the conclusion that CR is superior to PAS because of two methodological issues. First, the conclusion is not based on a formal test. We performed this test and found no evidence that CR predicted accuracy better than PAS . Second, Szczepanowski et al. used the present version of PAS in a manner somewhat different from how it was originally intended, and the participants may not have been adequately instructed. We end our commentary with a set of recommendations for future studies using PAS

In a recent article, [Sergent, C. & Dehaene, S. . Is consciousness a gradual phenomenon? Evidence for an all-or-none bifurcation during the attentional blink, Psychological Science, 15, 720–729] claim to give experimental support to the thesis that there is a clear transition between conscious and unconscious perception. This idea is opposed to theoretical arguments that we should think of conscious perception as a continuum of clarity, with e.g., fringe conscious states [Mangan, B. . Sensation’s ghost—the non-sensory “fringe” of consciousness, Psyche, 7, 18]. In the experimental study described in this article, we find support for this opposite notion that we should have a parsimonious account of conscious perception. Our reported finding relates to the hypothesis that there is more than one perceptual threshold [Merikle, P.M., Smilek, D. & Eastwood, J.D. . Perception without awareness: perspectives from cognitive psychology, Cognition, 79, 115–134], but goes further to argue that there are different “levels” of conscious perception

In their comment on Sandberg, Timmermans, Overgaard, and Cleeremans , Dienes and Seth argue that increased sensitivity of the Perceptual Awareness Scale is a consequence of the scale being less exclusive rather than more exhaustive. According to Dienes and Seth, this is because PAS may measure some conscious content, though not necessarily relevant conscious content, “If one saw a square but was only aware of seeing a flash of something, then one has not consciously seen a square.” In this reply, we claim that there is a difference between conscious visual experience, which may be partial, and the resulting conscious content, which is conceptual. Whereas PAS measures the first, confidence judgments and post-decision wagering measure the second

Blindsight is classically defined as residual visual capacity, e.g., to detect and identify visual stimuli, in the total absence of perceptual awareness following lesions to V1. However, whereas most experiments have investigated what blindsight patients can and cannot do, the literature contains several, often contradictory, remarks about remaining visual experience. This review examines closer these remarks as well as experiments that directly approach the nature of possibly spared visual experiences in blindsight.