Altered States Of Consciousness Research Articles

Glasgow Coma Scale: assessing consciousness for 50 years

The Glasgow Coma Scale, developed in 1974 by Teasdale and Jennett, has become a fundamental clinical tool in assessing consciousness and neurological response in patients with brain injuries or altered states of consciousness. Over the years, the Glasgow Coma Scale has undergone various modifications to improve its accuracy and applicability. In 2018, an enhanced version emerged, called the Glasgow Coma Scale with Pupillary Response, which included an additional criterion for assessing pupillary reactivity. The purpose of this article is to explore the temporal development of the Glasgow Coma Scale, its applications, and evolution over time. It is evident that the Glasgow Coma Scale continues to be an indispensable tool for assessing patients with altered consciousness, standing out for its simplicity and effectiveness. Its importance and adaptability in the medical field suggest that it will continue to evolve along with advances in medicine.

Virtual reality and neuromodulation in the induction of out-of-body experience (VR-NIOBE): A proof-of-concept new paradigm for psychological and neuroscientific study of an altered state of consciousness.

Virtual reality and neuromodulation in the induction of out-of-body experience (VR-NIOBE): A proof-of-concept new paradigm for psychological and neuroscientific study of an altered state of consciousness.

The secondary image as a psychocorrective resource: the search for new research opportunities

The authors consider in detail the problems of the "secondary image" in a historical context, as well as in modern research in connection with the state of the study of consciousness in philosophical and psychological concepts. The problem is the inattention of many, especially foreign authors, to this topic. The article considers the concept of "image-scheme" with the allocation of the "core" based on the primary image and the periphery of the figurative experience. In the article, the authors use a theoretical analysis based on the traditions of the Leningrad psychological school (B.G. Ananyev, B.F. Lomov), on the concept of "secondary image" in its correlation with primary sensory-perceptual images. Based on this basic content of images, the authors present a model of the formation and transformation of images in consciousness with the conditional allocation of a secondary image based on the traditions of the Leningrad psychological school. The correlation of the concept of "secondary image" with the images of "primary" – sensory-perceptual - is emphasized. The development of the theme of the "secondary image" in the context of its use in modern psychotherapeutic practice is proposed. In this regard, the relevance and theoretical significance of the problem of altered states of consciousness in general psychological and historical-psychological terms is emphasized. There is a high degree of multidimensionality and versatility of the figurative sphere as the most important component of consciousness. Based on the theoretical and methodological basis used, the author's vision of the topic is given in its application to the problem stated in the article. An adapted model of the formation and transformation of "primary" and "secondary" images in the stream of consciousness is proposed, highlighting the conditions for changing the integral imaginative sphere of a person in the psychocorrection process.

Changes in Intrinsic Connectivity Networks Topology Across Levels of Dexmedetomidine-Induced Alteration of Consciousness.

Human consciousness is generally thought to emerge from the activity of intrinsic connectivity networks (resting-state networks [RSNs]) of the brain, which have topological characteristics including, among others, graph strength and efficiency. So far, most functional brain imaging studies in anesthetized subjects have compared wakefulness and unresponsiveness, a state considered as corresponding to unconsciousness. Sedation and general anesthesia not only produce unconsciousness but also phenomenological states of preserved mental content and perception of the environment (connected consciousness), and preserved mental content but no perception of the environment (disconnected consciousness). Unresponsiveness may be seen during unconsciousness, but also during disconnectedness. Deep dexmedetomidine sedation is frequently a state of disconnected consciousness. In this study, we were interested in characterizing the RSN topology changes across 4 different and steady-state levels of dexmedetomidine-induced alteration of consciousness, namely baseline (Awake, drug-free state), Mild sedation (drowsy, still responding), Deep sedation (unresponsive), and Recovery, with a focus on changes occurring between a connected consciousness state and an unresponsiveness state. A functional magnetic resonance imaging database acquired in 14 healthy volunteers receiving dexmedetomidine sedation was analyzed using a method combining independent component analysis and graph theory, specifically looking at changes in connectivity strength and efficiency occurring during the 4 above-mentioned dexmedetomidine-induced altered consciousness states. Dexmedetomidine sedation preserves RSN architecture. Unresponsiveness during dexmedetomidine sedation is mainly characterized by a between-networks graph strength alteration and within-network efficiency alteration of lower-order sensory RSNs, while graph strength and efficiency in higher-order RSNs are relatively preserved. The differential dexmedetomidine-induced RSN topological changes evidenced in this study may be the signature of inadequate processing of sensory information by lower-order RSNs, and of altered communication between lower-order and higher-order networks, while the latter remain functional. If replicated in an experimental paradigm distinguishing, in unresponsive subjects, disconnected consciousness from unconsciousness, such changes would sustain the hypothesis that disconnected consciousness arises from altered information handling by lower-order sensory networks and altered communication between lower-order and higher-order networks, while the preservation of higher-order networks functioning allows for an internally generated mental content (or dream).

Neural complexity is increased after low doses of LSD, but not moderate to high doses of oral THC or methamphetamine.

Neural complexity correlates with one's level of consciousness. During coma, anesthesia, and sleep, complexity is reduced. During altered states, including after lysergic acid diethylamide (LSD), complexity is increased. In the present analysis, we examined whether low doses of LSD (13 and 26 µg) were sufficient to increase neural complexity in the absence of altered states of consciousness. In addition, neural complexity was assessed after doses of two other drugs that significantly altered consciousness and mood: delta-9-tetrahydrocannabinol (THC; 7.5 and 15 mg) and methamphetamine (MA; 10 and 20 mg). In three separate studies (N = 73; 21, LSD; 23, THC; 29, MA), healthy volunteers received placebo or drug in a within-subjects design over three laboratory visits. During anticipated peak drug effects, resting state electroencephalography (EEG) recorded Limpel-Ziv complexity and spectral power. LSD, but not THC or MA, dose-dependently increased neural complexity. LSD also reduced delta and theta power. THC reduced, and MA increased, alpha power, primarily in frontal regions. Neural complexity was not associated with any subjective drug effect; however, LSD-induced reductions in delta and theta were associated with elation, and THC-induced reductions in alpha were associated with altered states. These data inform relationships between neural complexity, spectral power, and subjective states, demonstrating that increased neural complexity is not necessary or sufficient for altered states of consciousness. Future studies should address whether greater complexity after low doses of LSD is related to cognitive, behavioral, or therapeutic outcomes, and further examine the role of alpha desynchronization in mediating altered states of consciousness.

Psilocybin-assisted psychotherapy for cancer patients

Despite significant advances in symptom management for patients affected by serious illness, physicians lack effective legal treatments for individuals suffering from demoralization, death anxiety, and existential distress. Psilocybin-assisted psychotherapy employs psilocybin-containing mushrooms or synthetic psilocybin grounded in indigenous traditions and within the context of a therapeutic mindset and environment ("set and setting") to achieve altered states of consciousness that promote healing and psychospiritual growth while reducing suffering. Current research evidence suggests that this form of therapy could serve as a safe and effective therapeutic tool for such patients.
 This presentation will describe a case series of patients with advanced cancer who received physician-supervised home-based psilocybin-assisted psychotherapy in Montreal, Canada. Our experience postulates the safety and efficacy of this laborious treatment process. By executing this clinical practice in the public healthcare system of Quebec for the first time, we have made an attempt to provide equitable access to these clinical therapies. Having performed these treatments outside the context of clinical trials, we have been able to tailor the therapeutic frame and treatment approach to a more patient-centric and culturally-informed manner. That being said, given the existing ​societal discrimination and stigma against this form of therapy, including by healthcare professionals, there remain further barriers to overcome in the equitable provision of care, especially to certain segments of the population. ​The authors will discuss these and potential solutions to addressing them.

Calling the tune in maladaptive daydreaming: The impact of music on the experience of compulsive fantasizing

This study aimed to shed light on the role of music in maladaptive daydreaming (MD), a psychological condition characterized by excessive, immersive daydreaming that interferes with well-being and functioning. Forty-one individuals with probable MD participated in asynchronous in-depth email interviews. A thematic analysis yielded three themes describing the role of music in MD. Two homogeneous themes pertained to outlier experiences: Music necessary and Music not desired. The third theme, Music enhances the MD experience, encompassed most of the data retrieved in this study and was further divided into five subthemes: Music avoided in “low energy” daydreaming scenes, Music as white noise, Music enhances MD creativity, Music as an MD trigger compromises the sense of agency; and Music as a powerful immerser that sets MD’s emotional “soundtrack.” This study adds to the sparse knowledge of complex visual narratives and identifies the essential role of music in inducing and formatting MD. The results led to the conclusion that music might be instrumental in MD by distancing the person from the external reality, triggering complex visual storylines, deepening the altered state of consciousness, and intensifying the vividness of the daydreamed plot by invoking an emotional response. Furthermore, hypothesis-driven controlled research was recommended.

Sacred Plants and Their Miraculous or Healing Properties

The purpose of this article is to study the 'sacred' plants’, diverse from those exclusively medicinal but with an unquestionable ethnobotanical value because, added to their healing properties, they develop mystical experiences and altered states of consciousness analogous to the ecstatic trance. _Psychoactive_ plants have played an important role in medicine, religion, _ritual_ life and recreation since ancient times and_ have been_ consumed by many cultures, cults and groups during religious rituals and ceremonies for centuries. Used in indigenous contexts and acting as divine intermediaries, they provide treatment for physical, psychological, spiritual and social symptoms, diagnosis and cure of diseases as well as supernatural experiences focused in religious rituals. First of all it will be interesting to analyze its perspectives on ritual, shamanism and ecstasy techniques, to reexamine the distinction between psychotropic, analgesic, stimulant and visionary substances, its distinguishing characteristics, the latest research on symbolic beliefs and the men's bodily reactions and effects produced by the ingestion. The altered states of consciousness (ASCs), induced by the badly called 'hallucinogenic' plants, include bodily sensations, intuitions, visions, dreams or cognitive impacts with perception of strange sounds that allow to get in touch with the deep psyche. People in this condition could activate emotionally arousing experiences that digging _deep_ to _unearth_ a well of _memories_, to face limitations, response to the basic emotion of fear, and even intensify physical pain to definitively cure it. Altered states of consciousness differ energetically on the dimensions of (a) arousal versus sedation, (b) pleasure versus pain, and (c) expansion versus contraction [1]. We will later provide some background on the different 'entheogenic' plants distinguishing their regional use and finally, by selecting two most ecologically representative species, mandrake and peyote, we will identify both basic characteristics and their long and very complex history. The similarities and differences between the mandrake, an ancestral toxic plant in force since ancient times, usually used in Western culture, and peyote, characteristic of the New World, will show us the strong biological effects produced by their powerful alkaloids in human organisms. The two have a long history of medicinal purposes, while peyote widely used both by drug abusers and by peoples of traditional cultures, stands out as a current psychedelic drug much sought after and consumed by Western intellectuals around 1960. It will be interesting to analyze their true characteristics and the symbolic beliefs that they aroused due to the strange effects that their ingestion produced.

Revising the core knowledge confusions scale: a measure of logical error associated with cognitive and personality traits

AbstractThe Core Knowledge Confusions scale (CKC) was designed to predict paranormal and spiritual beliefs, alternative health beliefs and the degree to which people assign meaning to events. It measures the likelihood of individuals' tendency to accept ontologically confused content as literally true and has been used to investigate beliefs such as the paranormal. However, the psychometric properties of the CKC have not been tested, limiting the scale’s practical utility. The CKC was revised and tested, internal consistency was checked, and associations to paranormal belief were assessed using a panel survey of 1010 Australian residents (Mage = 52, SD = 17.69, Female = 56%). Using structural equation modelling and regression, the revised scale (CKC-R) content deviated from previous findings. However, it demonstrated acceptable internal, construct, and divergent validity. External correlates of the CKC-R were aligned with expectations: associating with high verbal knowledge, an intuitive cognitive style, and the absorption personality trait (i.e., a tendency to experience altered states of consciousness). The CKC-R provides researchers with a validated measure predicting paranormal belief that is associated with both cognitive and personality-based traits. Interpretation of the CKC-R as a measure of ontological error is less clear and requires further investigation.

Supraglottic myxoedema successfully treated orally.

Myxoedema coma is a severe form of hypothyroidism with multiple organ dysfunction, characterised by an altered state of consciousness and hypothermia. Intravenous thyroid hormone replacement therapy is the preferred treatment for myxoedema. The mortality rate associated with this disease is high, and early detection and intervention are essential. Supraglottal myxoedema is a rare form of periglottic oedema and can be fatal. A previously healthy 66-year-old man presented with impaired consciousness, hypothermia, and nonpitting oedema. Blood tests revealed the presence of hypothyroidism and respiratory acidosis. He was intubated for type 2 respiratory failure; however, severe laryngeal oedema made the procedure difficult to perform. Oral thyroid hormone therapy was initiated under the diagnosis of myxoedema coma. Tracheostomy was performed because of prolonged type 2 respiratory failure and laryngeal oedema. Three weeks after admission, the patient was weaned off the ventilator. Approximately a week later, laryngeal oedema improved, and the tracheostomy tube was removed. The patient was discharged and remained stable for 3 months. This case report describes a patient with comatose myxoedema and supraglottic oedema who was successfully treated with oral medication alone. This case shows that supraglottic oedema should be considered even in the absence of wheezing or other signs of upper airway obstruction. Myxoedema coma is a differential diagnosis of respiratory acidosis. In myxoedematous coma, the possibility of difficult intubation due to supraglottic oedema should be considered. Tracheostomy should be considered for supraglottic myxoedema, which often results in prolonged ventilator use. Supraglottic myxoedema can be treated with oral medications.

Exploring effects of anesthesia on complexity, differentiation, and integrated information in rat EEG.

To investigate mechanisms underlying loss of consciousness, it is important to extend methods established in humans to rodents as well. Perturbational complexity index (PCI) is a promising metric of "capacity for consciousness" and is based on a perturbational approach that allows inferring a system's capacity for causal integration and differentiation of information. These properties have been proposed as necessary for conscious systems. Measures based on spontaneous electroencephalography recordings, however, may be more practical for certain clinical purposes and may better reflect ongoing dynamics. Here, we compare PCI (using electrical stimulation for perturbing cortical activity) to several spontaneous electroencephalography-based measures of signal diversity and integrated information in rats undergoing propofol, sevoflurane, and ketamine anesthesia. We find that, along with PCI, the spontaneous electroencephalography-based measures, Lempel-Ziv complexity (LZ) and geometric integrated information (ΦG), were best able to distinguish between awake and propofol and sevoflurane anesthesia. However, PCI was anti-correlated with spontaneous measures of integrated information, which generally increased during propofol and sevoflurane anesthesia, contrary to expectations. Together with an observed divergence in network properties estimated from directed functional connectivity (current results) and effective connectivity (earlier results), the perturbation-based results seem to suggest that anesthesia disrupts global cortico-cortical information transfer, whereas spontaneous activity suggests the opposite. We speculate that these seemingly diverging results may be because of suppressed encoding specificity of information or driving subcortical projections from, e.g., the thalamus. We conclude that certain perturbation-based measures (PCI) and spontaneous measures (LZ and ΦG) may be complementary and mutually informative when studying altered states of consciousness.

Music and the Altered State of Consciousness

"Tourists travelling to Turkey may encounter circling (mevlevi) dervishes in Konya, spinning in circles to achieve a kind of altered state of consciousness and enter a trance-like state of ecstasy. The world of popular music has also been inspired by the concepts of Christianity and ecstasy, and some rock bands have emerged from a combination of the two. This altered state of consciousness is brought about by the combined effect of dance and music, which they believe can be an ecstatic experience of dual action, freeing one from the agonies and pains of everyday life. In some religions, the ecstatic and altered state of consciousness is part of ritual and worship as a power unleashed. The question is, is there a place for music-induced ecstasy in Christian worship? In this sub-chapter, we will discuss the ecstatic effect of music, the altered state of consciousness experienced as a result, and the increasingly prevalent binaural beats and music at 432 hertz. Keywords: music, altered state of consciousness, ecstatic dimension, binaural beats, 440 Hz, rhythm"

Are tattoos symbols of transformation?

This research was motivated by the exponential interest in tattoos over the past four decades, which led to my research question: “Are tattoos symbols of transformation?” An examination of both current and historical literature generated an understanding of the tattoo process as a rite of passage, which considers the possibility of tattoos as transformative symbols between the mundane and transpersonal realms of existence. This generated a deeper understanding of tattoos from the essence of indigenous knowledge and why its revival is important in our current world context. The qualitative approach of intuitive inquiry was chosen for its creative and intuitive alignment with the subject of tattooing. The five hermeneutical cycles of intuitive inquiry aligned with the five stages of tattooing. Ten participants with personally meaningful tattoos were interviewed. Thematic analysis was applied to the data and five themes emerged: Ritual, symbol / non-verbal communication, pain, altered state / sacred dimension, and transformation. These themes were explored, revealing altered states of consciousness and embodiment, resulting in personal growth and an expansion in worldview. This research suggests that tattoos can be cultural and natural symbols carrying our stories and meaning through time, while restoring relationship to ourselves and a unified consciousness.

Når spiritualitet blir kroppslig

Spiritual awakening is becoming a common phenomenon in alternative spiritual communities and is no longer exclusive to a small elite of religious saints and disciples. There is limited research on spiritual experiences outside religious contexts in the Nordic countries. While relevant theological research exists on religious experiences in Christian contexts, much of the research on alternative spirituality is based on outsider perspectives that miss out on the deeper psychological phenomena experienced by “spiritual, but not religious” individuals. This article is based on three qualitative interviews with individuals in contemporary spiritual communities in Norway who have experienced spontaneous spiritual awakenings and speak openly about this. Focus is on the experience of altered states of consciousness, intense feelings of love, and physical energies in the body, which lead to permanent psychological transformation. Starting with a review of relevant Norwegian and Swedish research in the field, we apply a theoretical approach drawn from humanistic and transpersonal psychology to make sense of our interviewees’ experiences, and then discuss how these cases of embodied spiritual transformation differ from religious conversion and are better understood in terms of psychological concepts of trauma healing, self-actualization and human potential.

Opium Art and Truffle Texts in the Aegean and Ancient Near East

From the third millennium BC on, the opium poppy was exploited by the civilizations of the Aegean and Near East. While the terms for it in the ancient languages of the region are still unknown, the distinctive features of the harvest-ready seed pod would seem to find reflection in numerous works of Minoan, Mycenaean, Mesopotamian, and related art. This paper proposes that the corpus of opium imagery is far more extensive than previously recognized, including pins, finials, jewelry, seals, vessels, and weapons. It would also seem that certain elite women played vital roles in ancient opium matters. As for the desert truffle, it thrives in the area’s arid and semi-arid ecosystems, where the opium poppy cannot. We have no truffle art, so far as can be determined, but its suggestive presence in cuneiform documents, among them the seven Mari letters collected here, may signal that it was prized for its ability to engender altered states of consciousness, in addition to its nutritional and pharmaceutical benefits.

Hierarchical rhythmic propagation of corticothalamic interactions for consciousness: A computational study

Clarifying the mechanisms of loss and recovery of consciousness in the brain is a major challenge in neuroscience, and research on the spatiotemporal organization of rhythms at the brain region scale at different levels of consciousness remains scarce. By applying computational neuroscience, an extended corticothalamic network model was developed in this study to simulate the altered states of consciousness induced by different concentration levels of propofol. The cortex area containing oscillation spread from posterior to anterior in four successive time stages, defining four groups of brain regions. A quantitative analysis showed that hierarchical rhythm propagation was mainly due to heterogeneity in the inter-brain region connections. These results indicate that the proposed model is an anatomically data-driven testbed and a simulation platform with millisecond resolution. It facilitates understanding of activity coordination across multiple areas of the conscious brain and the mechanisms of action of anesthetics in terms of brain regions.

Clinical and systems of care factors contributing to individual patient decision-making for early mobilization post-stroke

IntroductionMany stroke guidelines recommend against starting intensive out-of-bed activity (mobilization) within 24 h post-stroke. Few guidelines address care after the first 24–48 h, and little information is provided about how early mobilization decisions should be tailored to patients. We aimed to identify clinical and systems of care factors contributing to individual patient decision-making for early mobilization post-stroke.MethodsExpert stroke clinicians were recruited to participate in an interactive one-on-one session that included an introductory semi-structured interview followed by an assisted data exploration session using an early mobilization data visualization tool.ResultsThirty expert stroke clinicians with a median (interquartile range) 14 (10–25) years of experience were included. Stroke type and severity, and medical stability were identified as important clinical decision-making factors by the majority of expert stroke clinicians. Inadequate staffing and equipment were frequently indicated as barriers to early mobilization. The perceived characteristics of early mobilization responders were mild or moderate stroke severity, ischemic stroke, partial anterior circulation stroke, younger age, and one or fewer comorbidities. Perceived characteristics of early mobilization non-responders included severe stroke severity, hemorrhagic stroke, total anterior circulation stroke, older age, those with persistent vessel occlusion or high-grade stenosis, hemodynamic instability, multimorbidity and an altered state of consciousness. Some characteristics led to uncertainty amongst interviewees e.g., early mobilization decision-making were moderate stroke severity, older patients, and those with lacunar circulation infarcts.DiscussionWe gained unique, in-depth insights into patient and systems of care factors that contribute to individual patient decision-making related to early mobilization post-stroke. The identified areas would benefit from further empirical research to develop structured decision support for clinicians.

Shared functional connectome fingerprints following ritualistic ayahuasca intake

The knowledge that brain functional connectomes are unique and reliable has enabled behaviourally relevant inferences at a subject level. However, whether such “fingerprints” persist under altered states of consciousness is unknown. Ayahuasca is a potent serotonergic psychedelic which produces a widespread dysregulation of functional connectivity. Used communally in religious ceremonies, its shared use may highlight relevant novel interactions between mental state and functional connectome (FC) idiosyncrasy. Using 7T fMRI, we assessed resting-state static and dynamic FCs for 21 Santo Daime members after collective ayahuasca intake in an acute, within-subject study. Here, connectome fingerprinting revealed FCs showed reduced idiosyncrasy, accompanied by a spatiotemporal reallocation of keypoint edges. Importantly, we show that interindividual differences in higher-order FC motifs are relevant to experiential phenotypes, given that they can predict perceptual drug effects. Collectively, our findings offer an example of how individualised connectivity markers can be used to trace a subject's FC across altered states of consciousness.

Acute psychotropic, autonomic, and endocrine effects of 5,6-methylenedioxy-2-aminoindane (MDAI) compared with 3,4-methylenedioxymethamphetamine (MDMA) in human volunteers: A self-administration study.

The acute psychoactive, autonomic, and endocrine effects of the new psychoactive substance (NPS) 5,6-methylenedioxy-2-aminoindane (MDAI; 3.0mg/kg, range 180-228 mg) were investigated in six healthy volunteers (four males, two females) in a non-blinded fashion without placebo. Subjective, cardiovascular, and endocrine responses were compared with two different doses of 3,4-methylenedioxymethamphetamine (MDMA) (75 mg and 125 mg) described in previously published placebo-controlled studies, which used identical outcome measures including Visual Analogue Scales (VAS), the Adjective Mood Rating Scale (AMRS), and the 5 Dimensions of Altered States of Consciousness (5D-ASC) scale. MDAI was well tolerated and produced subjective effects comparable with those of 125 mg MDMA. MDAI increased blood pressure similar to 125 mg MDMA but did not increase heart rate or body temperature. MDAI increased cortisol and prolactin levels and could be detected in serum about 20 min post ingestion and remained detectable at least for 4days. In urine, MDAI was detectable over a period of at least 6days. Further clinical investigations are warranted to assess whether MDAI could serve as drug with medicinal properties.

Thalamocortical dysrhythmia in patients with delirium: an EEG possible marker of prodromal dementia with Lewy bodies

AbstractBackgroundEEG in DLB is characterized by pre‐alpha dominant frequency (DF) [6–7.5] Hz. The appearance of prealpha rhythm in the cortex is linked to a dysfunctional thalamocortical connection, the thalamocortical dysrhythmia (TCD). The hypothesis that TCD is implicated in DLB has been demonstrated by several structural, functional, and molecular imaging studies. TCD has been implicated in the appearance of altered conscious states, including fluctuating cognition and delirium, two clinical core features of DLB. Delirium can represent the onset of DLB and is listed among the symptoms of prodromal DLB. We aimed to assess specific QEEG abnormalities akin to those found in DLB, also in delirium, to detect a prodromal stage of DLB.MethodCross‐sectional multicentre cohort study and longitudinal prospective study, nested in the multicentre. rsEEG activity was compared in hospitalized patients with delirium vs. patients without delirium. In a subset of 23 patients, rsEEG was also recorded in patients with delirium at resolution of symptom and and at 1‐month follow‐up. DF and DF variability (DFV) were analysed. ResultCross‐sectional multicentre study: 65 subjects with acute delirium were matched for age/sex with 41 controls. Abnormal EEGs were found in 100% delirium patients vs. 34% no‐delirium patients. DF was lower in delirium group (p<0.001), which showed pre‐alpha DF; no‐delirium group had alpha DF. DFV was higher in delirium group (p<0.001). Single‐centre longitudinal study: After delirium resolution, 21 patients had EEG normalization and were cognitively unimpaired. 2 patients had abnormal EEG and were respectively diagnosed as DLB and MCI.ConclusionAcute delirium was characterized by pre‐alpha rhythm, expression of TCD. In most patients EEG normalized after resolution, making EEG a state marker of acute delirium, when the thalamocortical system becomes unstable, but it is still able to recover. TCD may become unrecoverable when the neurodegenerative process of DLB progresses.