Establishing the neural mechanisms responsible for the altered global states of consciousness during anesthesia and dissociating these from other drug-related effects remains a challenge in consciousness research. We investigated differences in brain activity between connectedness and disconnectedness by administering various anesthetics at concentrations designed to render 50% of the subjects...
Recent years have seen a growing interest in the use of measures inspired by complexity science for the study of consciousness. The work done in this field has shown remarkable results in discerning conscious from unconscious states, and in characterizing states of altered conscious experience following intake of psychedelic substances as involving enhanced complexity. However, the relationship...
Psychedelics such as psilocybin reliably produce significantly altered states of consciousness with a variety of subjectively experienced effects. These include certain changes to perception, cognition, and affect,1 which we refer to here as the acute subjective effects of psychedelics. In recent years, psychedelics such as psilocybin have also shown considerable promise as therapeutic agents...
Interest in dream and madness, conceived as the loss of a world shared with others, and the individual’s entry into a private world governed by a personal logic unrelated to the waking state and to common feeling, recurs in at least three of Kant’s works: Essay on the Diseases of the Head, (1764), Dreams of a Spirit-Seer (1766), and Anthropology from a Pragmatic Point of View (1798). Hegel too,...
Abstract Psychedelics are a broad class of drugs defined by their ability to induce an altered state of consciousness 1,2 . These drugs have been used for millennia in both spiritual and medicinal contexts, and a number of recent clinical successes have spurred a renewed interest in developing psychedelic therapies 3–9 . Nevertheless, a unifying mechanism that can account for these shared...
Primary states of consciousness are conceived as phylogenetically older states of consciousness as compared to secondary states governed by sociocultural inhibition. The historical development of the concept in psychiatry and neurobiology is reviewed, along with its relationship to theories of consciousness. We suggest that primary states of consciousness are characterized by a temporary...
PURPOSE OF REVIEW: In this review, we summarize the current understanding of consciousness including its neuroanatomic basis. We discuss major theories of consciousness, physical exam-based and electroencephalographic metrics used to stratify levels of consciousness, and tools used to shed light on the neural correlates of the conscious experience. Lastly, we review an expanded category of...
SUMMARY: Substantial changes in behavior, physiology, and brain function occur when alertness decreases 1– 5 . These changes in brain function involve increased synchronization between cortical areas 6,7 as well as alterations in sensory processing pathways and networks connecting the thalamus and cortex 5,8–11 . Cognitive tasks engage overlapping functional networks with sensory pathways...
We used a multiteam system approach (MTS) to map the critical and constructive feedback from four invited Commentaries on Rock et al.’s (2023) probabilistic analysis of purported evidence for postmortem survival. The goal was to mine actionable insights to guide future research with the potential for important learnings or breakthroughs about the nature or limits of human consciousness and...
Recent studies have begun to understand sleep not only as a whole-brain process but also as a complex local phenomenon controlled by specific neurotransmitters that act in different neural networks, which is called "local sleep". Moreover, the basic states of human consciousness-wakefulness, sleep onset (N1), light sleep (N2), deep sleep (N3), and rapid eye movement (REM) sleep-can concurrently...