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.

In the present paper it is argued that the “neural correlate of consciousness” (NCC) does not appear to be a separate “module” – but an aspect of information processing within the neural substrate of various cognitive processes. Consequently, NCC can only be addressed adequately within frameworks that model the general relationship between neural processes and mental states – and take into account the dynamic connectivity of the brain. We presently offer the REFGEN (General Reorganization of Elementary Functions) model as such a framework. This model builds upon and expands the REF (Reorganization of Elementary Functions) and REFCON (Reorganization of Elementary Functions and Consciousness) models. All three models integrate the relationship between the neural and mental layers of description via the construction of an intermediate level dealing with computational states. The importance of experience based organization of neural and cognitive processes is stressed. The models assume that the mechanisms of consciousness are in principle the same as the basic mechanisms of all aspects of cognition – when information is processed to a sufficiently “high level” it becomes available to conscious experience. The NCC is within the REFGEN model seen as aspects of the dynamic and experience driven reorganizations of the synaptic connectivity between the neurocognitive “building blocks” of the model – the Elementary Functions.

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.

We describe a patient LS, profoundly deaf in both ears from birth, with underdeveloped superior temporal gyri. Without hearing aids, LS displays no ability to detect sounds below a fixed threshold of 60 dBs, which classifies him as clinically deaf. Under these no-hearing-aid conditions, when presented with a forced-choice paradigm in which he is asked to consciously respond, he is unable to make above-chance judgments about the presence or location of sounds. However, he is able to make above-chance judgments about the content of sounds presented to him under forced-choice conditions. We demonstrated that LS has faint sensations from auditory stimuli, but questionable awareness of auditory content. LS thus has a form of type-2 deaf hearing with respect to auditory content. As in the case of a subject with acquired deafness and deaf hearing reported on a previous occasion, LS’s condition of deaf hearing is akin in some respects to type-2 blindsight. As for the case of type 2 blindsight the case indicates that a form of conscious hearing can arise in the absence of a fully developed auditory cortex.

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