Philosophical transactions of the Royal Society of London. Series B, Biological sciences
September 19, 2018
Morten Overgaard
62 citations
In consciousness research, phenomenal consciousness (subjective experience) is often distinguished from access consciousness (cognitive availability). Some scientists, notably Ned Block, argue that phenomenal content can exceed what is cognitively accessed—a claim known as 'overflow'. This review examines the evidence and concludes that existing data do not demonstrate overflow. Overflow is theoretically possible but extremely difficult to prove if 'cognitive access' is defined as working memory or attention. However, if 'access' means information becoming 'cognitively available' in a broader sense, then a separation between subjective experience and access is impossible.
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
September 19, 2018
Peter Fazekas, Morten Overgaard
30 citations
The problem of explaining how subjective experiences like colors, sounds, and tastes arise from brain processes is often considered the greatest unsolved mystery. A key question is whether the neural basis of perceptual consciousness is separate from the neural basis of cognitive access mechanisms that allow reporting and reflecting on conscious experiences. This Theme Issue critically discusses current empirical findings, identifies methodological problems, and proposes novel approaches to this central issue in consciousness research.
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
September 19, 2018
Jesper Mogensen, Morten Overgaard
17 citations
Phenomenal consciousness cannot overflow the availability of information for action, but it may overflow working memory, which is seen as a surface phenomenon reflecting underlying dynamic strategies. This conclusion comes from the REF (reorganization of elementary functions) framework, a neurocognitive model based on connectionist networks where advanced processing modules called elementary functions reorganize connectivity to form dynamic strategies rather than fixed cognitive functions. The neural correlate of consciousness is understood within these models as tied to such reorganizations, and working memory is influenced by both experience and situational factors.
Front Psychol
September 23, 2025
Asger Kirkeby-Hinrup, Andreas Stephens, Aron Balogh Sjöstrand et al.
4 citations
The authors examine methodological challenges in consciousness research, focusing on how theories are compared, the role of empirical evidence, and a replication crisis. They argue that current approaches often lack rigorous theory comparison and that empirical evidence is sometimes insufficiently linked to theoretical predictions. The replication crisis further undermines confidence in findings. The paper calls for improved methods to ensure more reliable progress in understanding consciousness.
Communications psychology
November 26, 2025
Morten Overgaard, Peter Fazekas, Asger Kirkeby-Hinrup et al.
The field of consciousness research lacks consensus due to reliance on competing grand theories. A more productive path forward would shift focus toward construct-based, data-driven, and iterative approaches that identify empirical building blocks of conscious experience, enabling cumulative and integrative progress.
The European journal of neuroscience
November 1, 2022
Lau M Andersen, Mikkel C Vinding, Kristian Sandberg et al.
The neural correlates of consciousness may not be fixed within a single brain region; instead, they can shift depending on the task a person performs. Using magnetoencephalography, researchers compared a perceptual task and a conceptual task that used identical visual stimuli. The perceptual task recruited more occipital brain activity than the conceptual task, while frontal activity varied between the two tasks in partly unexpected ways depending on the level of perceptual awareness. These results suggest that what a person is doing—the task at hand—influences which brain areas support conscious perception, challenging the idea that consciousness can be localized to a consistent set of regions.
Consciousness and cognition
September 1, 2022
Timo L Kvamme, Mesud Sarmanlu, Morten Overgaard
A double-blind neurofeedback study tested whether participants could become aware of the experiment's purpose. Using a contingency awareness questionnaire developed from consciousness research, 5 out of 20 subjects correctly guessed that the experiment aimed to manipulate their attention and multisensory perception in line with their group assignment. The questionnaire took about 25 minutes to complete. The authors call for replication before applying the questionnaire in clinical neurofeedback studies, noting both the strengths and limitations of the approach and the increasing importance of double-blinding in this field.
Cortex; a journal devoted to the study of the nervous system and behavior
November 1, 2019
María Hernández-Lorca, Kristian Sandberg, Dominique Kessel et al.
Conscious perception of emotional images is linked to brain activity in the visual awareness negativity (VAN) time range (130–320 ms after stimulus onset), which is the earliest neural correlate of consciousness and extends beyond simple visual features. An emotional modulation of event-related potentials—termed emotional content awareness modulation (ECAM)—appears at this VAN latency. In binocular rivalry, where neutral and emotional images compete for conscious perception, positive valence is more likely to dominate as the first percept, indicating an emotional bias toward positive content. Negative and positive emotional content modulate conscious perception differently. These findings connect early perceptual brain activity with emotional influences on what we consciously see.