Consciousness science is fragmented, and empirical investigations are confined within each theory of consciousness’ (TOC) framework. Proliferating ToCs accumulate anomalies without progress, operating orthogonally. The principle of recurrency – functional and architectural – offers a unifying, mechanistic scaffold for consciousness to arise. We show that all theories tacitly invoke feedback...
A popular view holds that mental experiences uniquely differ between wakefulness and sleep, yet recent work suggests continuity across these stages. Here, we address this question by examining the wake-sleep transition, a window marked by rapid shifts in wake/sleep stages and mental experiences. We recorded electroencephalography (EEG) activity in 92 participants during two daytime resting...
A main characteristic of biological systems is their capacity to dynamically adapt to environmental changes. In the brain, synaptic plasticity enables the strengthening or weakening of connections between neurons, allowing neural circuits to adapt based on experience, learning, and environmental changes. Yet, it is homeostatically regulated such that it avoids excessive proliferation of...
Conscious experience depends on the coordinated activity of neural processes that span multiple scales: from synapses to whole-brain dynamics. A recently introduced measure, dynamical independence (DI), identifies, characterises, and quantifies these multi-scale relationships using an information-theoretic dimensionality reduction approach. Here, we use DI to examine changes in the emergent...
Does being awake necessarily mean being conscious of something? This study investigates the phenomenon of mind blanking (MB), characterized by an "emptiness of mind," comparing it with mind wandering (MW) and on-task (ON) states. Using a sustained attention task and electroencephalogram monitoring, behavioral, and neurophysiological signatures of MB were examined in 62 participants. MB...
Lucid dreaming (LD) – in which dreamers become aware that they are currently dreaming – has gained increasing attention in consciousness studies, yet its fine-grained experiential dynamics remain undercharacterized. We conducted in-depth micro-phenomenological interviews on 22 signal-verified lucid dreams experienced in a controlled sleep-laboratory setting, mapping within-episode dynamics from...
Ketamine is an NMDA-receptor antagonist, which alters the state of wakeful consciousness at high doses. At lower doses, it induces reversible psychotic-like symptoms and has been used as a pharmacological model of psychosis. In this study, we explore whether low doses of ketamine disrupt conscious access in relation with its psychotomimetic effects, and investigate the neural correlates of its...
Consciousness research is commonly divided into two main areas: the study of states of consciousness and the study of contents of consciousness. States of consciousness refer to discrete modes of awareness elicited by normal states of the brain, such as those associated with wakefulness and sleep, and by abnormal factors, including brain lesions, pharmacological agents and other external...
Magneto/electroencephalography (M/EEG) studies of dreaming are an essential paradigm in the investigation of neurocognitive processes of human consciousness during sleep, but they are limited by the number of observations that can be collected per study. Dream research also involves substantial methodological and conceptual variability, which poses problems for the integration of results. To...
Conscious experience depends on the coordinated activity of neural processes that span multiple scales—from synapses to whole-brain dynamics. A recently introduced measure, dynamical independence, identifies, characterises and quantifies these multi-scale relationships using an information-theoretic dimensionality-reduction approach. Here, we use DI to examine changes in emergent dynamical...
During wakefulness, our thoughts transition between different contents. However, there are moments that are seemingly devoid of reportable content, referred to as mind blanking (MB). It remains unclear what these blanks represent, highlighting the definitional and phenomenological ambiguities surrounding MB. We map out MB in terms of its reportable expressions, neurophysiology, and relationship...
Fluctuations in the presence, experiential quality and contents of consciousness occur naturally during sleep and wakefulness and are core features of the healthy human mind. The purpose of this article is to consider the possibility that such fluctuations, including mind wandering and dreaming, which we refer to collectively as spontaneous thoughts and experiences (STE), may also be important...
Attention shapes our consciousness content and perception by increasing the probability of becoming aware and/or better encoding a selection of the incoming inner or outer sensory world. Engaging interoceptive and exteroceptive attention should elicit distinctive neural responses to visceral and external stimuli and could be useful in detecting covert command-following in unresponsive patients....
Understanding what makes us conscious is one of the major frontiers of science. There are two main approaches to the mystery of consciousness. The first regards conscious states (i.e., being conscious) and how certain global states (e.g., of arousal) can support the formation of any conscious experience. Insights into the neural processes underlying the capacity for consciousness stem from...
Wakefulness, non-rapid eye-movement (NREM) and rapid eye-movement (REM) sleep differ from each other along three dimensions: behavioral, phenomenological, physiological. Although these dimensions often fluctuate in step, they can also dissociate. The current paradigm that views sleep as made of global NREM and REM states fail to account for these dissociations. This conundrum can be dissolved...
Magneto/electroencephalography (M/EEG) studies of dreaming are an essential paradigm in the investigation of neurocognitive processes of human consciousness during sleep, but they are limited by the number of observations that can be collected per study. Dream research also involves substantial methodological and conceptual variability, which poses problems for the integration of results. To...
Attentional lapses occur commonly and are associated with mind wandering, where focus is turned to thoughts unrelated to ongoing tasks and environmental demands, or mind blanking, where the stream of consciousness itself comes to a halt. To understand the neural mechanisms underlying attentional lapses, we studied the behaviour, subjective experience and neural activity of healthy participants...
Abstract Attentional lapses are ubiquitous and can negatively impact performance. They correlate with mind wandering, or thoughts that are unrelated to ongoing tasks and environmental demands. In other cases, the stream of consciousness itself comes to a halt and the mind goes blank. What happens in the brain that leads to these mental states? To understand the neural mechanisms underlying...
Sleep leads to a disconnection from the external world. Even when sleepers regain consciousness during rapid eye movement (REM) sleep, little, if any, external information is incorporated into dream content [1-3]. While gating mechanisms might be at play to avoid interference on dreaming activity [4], a total disconnection from an ever-changing environment may prevent the sleeper from promptly...
We spend a third of our lives asleep, and sleep teems with vivid dreams. While most people rarely remember their dreams, laboratory studies using timed awakenings show that healthy adults experience multiple dreams per night. Dreams have been hypothesised to play a key role in the development of consciousness and cognition1,2. Dreams are believed to contribute to sleep-related memory...
In their recent article, the unfolding argument, Doerig et al argue that a theory of consciousness cannot be based in the characterization of the physical structure of the brain. They argue that such theories must be “either false or outside the realm of science”. Instead, they prefer theories of consciousness based only on “input-output” descriptions. By their implicit treatment of phenomenal...