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1.
Front Psychol ; 15: 1112103, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558777

RESUMO

Psychedelic substances are known to facilitate mystical-type experiences which can include metaphysical beliefs about the fundamental nature of reality. Such insights have been criticized as being incompatible with naturalism and therefore false. This leads to two problems. The easy problem is to elaborate on what is meant by the "fundamental nature of reality," and whether mystical-type conceptions of it are compatible with naturalism. The hard problem is to show how mystical-type insights, which from the naturalistic perspective are brain processes, could afford insight into the nature of reality beyond the brain. I argue that naturalism is less restrictive than commonly assumed, allowing that reality can be more than what science can convey. I propose that what the mystic refers to as the ultimate nature of reality can be considered as its representation- and observation-independent nature, and that mystical-type conceptions of it can be compatible with science. However, showing why the claims of the mystic would be true requires answering the hard problem. I argue that we can in fact directly know the fundamental nature of one specific part of reality, namely our own consciousness. Psychedelics may amplify our awareness of what consciousness is in itself, beyond our conceptual models about it. Moreover, psychedelics may aid us to become aware of the limits of our models of reality. However, it is far from clear how mystical-type experience could afford access to the fundamental nature of reality at large, beyond one's individual consciousness. I conclude that mystical-type conceptions about reality may be compatible with naturalism, but not verifiable.

2.
Front Psychol ; 15: 1341430, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558781

RESUMO

Understanding consciousness is central to understanding human nature. We have competing theories of consciousness. In interdisciplinary consciousness studies most believe that consciousness can be naturalized (i.e., consciousness depends in some substantial way on processes in - or states of - the brain). For roughly two decades, proponents of almost every theory have focused on collecting empirical support for their preferred theory, on the tacit assumption that empirical evidence will resolve the debates. Yet, it remains unclear how empirical evidence can do this in practice. Here I address this issue by offering (a sketch of) a methodology to quantify the divergent sets of empirical support proposed in favor of extant theories of consciousness. This in turn forms the foundation for a process of inference to the best explanation inspired by Bayesian confirmation theory. In interdisciplinary consciousness studies we are blessed with an abundance of theories, but we have reached a point where, going forward, it would be beneficial to focus on the most promising ones. Methods for assessment and comparison are necessary to identify which those are. While future refinement is likely, the methodology for assessment and comparison proposed here is a first step toward a novel way of approaching this through a quantification of empirical support for theories of consciousness.

3.
Heliyon ; 10(7): e27872, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560259

RESUMO

Climate change constitutes one of the greatest threats to human health globally and there have been increasing interests in understanding the dynamics of climate change consciousness particularly in less industrialised countries of Africa. Research on cross-country, sub-regional and continent differences in climate change consciousness are rare especially in sub-Saharan Africa. Thus, to complement the existing body of literature, this study was conducted on cross-national predictors of public climate change consciousness. Data from the Afrobarometer round 7 for thirty-four [34] African countries, collected between 2017 and 2020, were used to investigate the influence of geographical, socio-demographics, and source of information on public consciousness of climate change. Statistical analyses of t-test, ANOVA and multiple regression were conducted to test the formulated hypotheses. Results showed a low level of climate change consciousness (CCC) among participants. Radio news was the major source of information for the sampled African citizens. There were significant differences in the CCC of male and female as well as between urban and rural respondents. Significant differences were also found among the sub-regions, educational levels, age groups and occupations. Sources of information and demographic variables significantly influenced the level of CCC among participating citizens. Educational attainment was the single most potent predictor of climate change consciousness. The study recommends that African citizens need capacity building on climate change awareness and initiatives which would assist in mitigating the effects of climate change.

5.
Cureus ; 16(3): e55356, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38562348

RESUMO

Triflumizole (TFZ) is a fungicide widely used in agriculture to prevent fungal infections of fruits and vegetables. Although it is considered safe for humans and animals, its toxicity profile in humans remains largely unexplored. Here, we describe a case where an individual experienced symptoms suggestive of intoxication after ingesting TFZ emulsion. A 70-year-old man ingested TFZ emulsion (Trifumin emulsionTM) and alcohol in an attempt to commit suicide. He developed a severe disturbance of consciousness, which was not explained by the estimated blood alcohol concentration, and experienced convulsions. We managed this patient with symptomatic treatment, temporary mechanical ventilation, and antiepileptic drugs. He subsequently recovered without any sequelae. We present the first case of acute oral intoxication with TFZ emulsion. Moreover, we review the literature on TFZ-induced organ dysfunction and discuss the possible mechanisms and management of this condition.

6.
Neurosci Conscious ; 2024(1): niae015, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38595737

RESUMO

The neurobiology of conscious experience is one of the fundamental mysteries in science. New evidence suggests that transcranial magnetic stimulation of the parietal cortex does not modulate bistable perception. What does this mean for the neural correlates of consciousness, and how should we search for them?

7.
World Neurosurg ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38599375

RESUMO

OBJECTIVE: To analyse the factors related to the efficacy of consciousness-regaining therapy for prolonged disorder of consciousness. METHODS: A retrospective analysis was conducted on the case data of 114 patients with pDOC admitted to the Department of Functional Neurosurgery of Tianjin Huanhu Hospital from January 2019 to January 2022 to explore the relevant factors that affect the efficacy of consciousness-regaining therapy (CRT) for prolonged disorder of consciousness (pDOC). Next, basic information on the cases, data on pDOC disease assessment, CRT methods, and efficacy evaluation were collected. RESULTS: These 114 patients were grouped, and a comparative analysis was done based on the efficacy at the end of treatment. Of these, 61 cases were allotted to the ineffective group and 53 cases to the effective group. There was a lack of statistical difference (P > 0.05) between the two groups based on gender, age, etiology, acute cerebral herniation, emergency craniotomy surgery, emergency decompressive craniectomy, time from onset to start of CRT, and CRT duration (P > 0.05). However, secondary hydrocephalus, CRT methods, CRS-R grading before treatment, and GOSE score at six months after treatment were found to be statistically different. The results of binary logistic regression analysis showed that the type of therapy (OR = 0.169, 95% CI: 0.057-0.508) affected the efficacy of CRT (P < 0.05). CONCLUSIONS: Personalized awakening therapy using various invasive CRT methods could improve the efficacy of therapy for pDOC compared with non-invasive therapy.

8.
Neurol Sci ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38589770

RESUMO

BACKGROUND: Transcranial direct current stimulation (tDCS) has been used for the restoration of awareness in patients with a minimal consciousness state (MCS). Most brains of patients in MCS may structurally and electrophysiologically differ from un-damaged brains. Moreover, tDCS is currently contraindicated for patients with craniotomy or skull with metallic implants. CASE PRESENTATION: We present a case with prolonged MCS over 1 year, who had severe brain damage, ventriculoperitoneal shunt, and cranioplasty with a titanium mesh, which was treated with tDCS which optimized with the simulation of the electric field based on the patient's brain MRI. The patient was resulting in emergence from MCS. Six months later, she ate meals orally and started walking with assistance. DISCUSSION AND PERSPECTIVE: This personalized simulation based on MRI would make the treatment available even to patients with severe brain structural changes and metallic instrumentation.

9.
Drug Des Devel Ther ; 18: 1025-1034, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585256

RESUMO

Purpose: Explore the median effective dose of ciprofol for inducing loss of consciousness in elderly patients and investigate how frailty influences the ED50 of ciprofol in elderly patients. Patients and Methods: A total of 26 non-frail patients and 28 frail patients aged 65-78 years, with BMI ranging from 15 to 28 kg/m2, and classified as ASA grade II or III were selected. Patients were divided into two groups according to frailty: non-frail patients (CFS<4), frail patients (CFS≥4). With an initial dose of 0.3 mg/kg for elderly non-frail patients and 0.25 mg/kg for elderly frail patients, using the up-and-down Dixon method, and the next patient's dose was dependent on the previous patient's response. Demographic information, heart rate (HR), oxygen saturation (SpO2), mean blood pressure (MBP), and bispectral index (BIS) were recorded every 30 seconds, starting from the initiation of drug administration and continuing up to 3 minutes post-administration. Additionally, the total ciprofol dosage during induction, occurrences of hypotension, bradycardia, respiratory depression, and injection pain were recorded. Results: The calculated ED50 (95% confidence interval [CI]) and ED95 (95% CI) values for ciprofol-induced loss of consciousness were as follows: 0.267 mg/kg (95% CI 0.250-0.284) and 0.301 mg/kg (95% CI 0.284-0.397) for elderly non-frail patients; and 0.263 mg/kg (95% CI 0.244-0.281) and 0.302 mg/kg (95% CI 0.283-0.412) for elderly frail patients. Importantly, no patients reported intravenous injection pain, required treatment for hypotension, or experienced significant bradycardia. Conclusion: Frailty among elderly patients does not exert a notable impact on the median effective dose of ciprofol for anesthesia induction. Our findings suggest that anesthesiologists may forego the necessity of dosage adjustments when administering ciprofol for anesthesia induction in elderly frail patients.


Assuntos
Anestesia , Fragilidade , Hipotensão , Idoso , Humanos , Fragilidade/tratamento farmacológico , Bradicardia/induzido quimicamente , Hipotensão/induzido quimicamente , Hipotensão/tratamento farmacológico , Dor , Inconsciência
10.
Neurosci Conscious ; 2024(1): niae016, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585293

RESUMO

Consciousness arguably presents a "hard problem" for scholars. An influential position asserts that the "problem" is rooted in ontology-it arises because consciousness "is" distinct from the physical. "Problem intuitions" are routinely taken as evidence for this view. In so doing, it is assumed that (i) people do not consider consciousness as physical and (ii) their intuitions faithfully reflect what exists (or else, intuitions would not constitute evidence). New experimental results challenge both claims. First, in some scenarios, people demonstrably view consciousness as a physical affair that registers in the body (brain). Second, "problem intuitions" are linked to psychological biases, so they cannot be trusted to reflect what consciousness is. I conclude that the roots of the "hard problem" are partly psychological. Accordingly, its resolution requires careful characterization of the psychological mechanisms that engender "problem intuitions."

11.
Respir Med ; 226: 107624, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38570143

RESUMO

Assessment of self-conscious emotions is important to develop tailored interventions for people with chronic obstructive pulmonary disease (COPD). Previous instruments have largely been developed for mental health populations. The Self-Conscious Emotions in COPD Questionnaire was the first instrument to assess self-conscious emotions in people with COPD, but it was only available in English. The aim was to translate the Self-Conscious Emotions in COPD Questionnaire into Swedish and to evaluate its psychometric properties and internal structure in a Swedish context. The translation process included forward and backward translation, a multidisciplinary meeting, assessment of content validity, and cognitive interviews. The translated instrument was tested in a sample of 173 people with COPD between September 2021 and September 2022. Parallel analysis (PA), exploratory factor analysis (EFA), and test-retest reliability was performed. The content validity index (CVI) for the instrument was 0.88. Based on the PA, an EFA with a two-factor solution was conducted, with a high Cronbach's alpha (0.786-0.821), and one item about self-blame was excluded. The two factors were labelled: The burden of living with a disability and The desire to hide vulnerability. Test-retest reliability showed no difference between scale scores on factor or item level, except for one item. The Swedish Self-Conscious Emotions in COPD showed good validity and reliability. One item was excluded from the two subscales, indicating that the instrument needs to be further developed to cover the concept of self-blame. The instrument is expected to be a valuable tool for assessing self-conscious emotions in people with COPD.

12.
Physiol Rep ; 12(7): e16000, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38584117

RESUMO

Few standardized tools are available for evaluation of disorders of consciousness (DOC). The potential of heart rate variability (HRV) during head-up tilt (HUT) test was investigated as a complementary evaluation tool. Twenty-one DOC patients and 21 healthy participants were enrolled in this study comparing clinical characteristics and HRV time- and frequency-domain outcomes and temporal changes during HUT test. During the 1st-5th min of the HUT, DOC group showed a significant increase and decrease in log low frequency (LF) (p = 0.045) and log normalized high frequency (nHF) (p = 0.02), respectively, compared to the supine position and had lower log normalized LF (nLF) (p = 0.004) and log ratio of low-to-high frequency (LF/HF) (p = 0.001) compared to healthy controls. As the HUT continued from the 6th to the 20th min, DOC group exhibited a significant increase in log LF/HF (16th-20th min) (p < 0.05), along with a decrease in log nHF (6th-10th and 16th-20th min) (p < 0.05) and maintained lower log LF, log nLF, and log LF/HF than controls (p < 0.05). 1st-10th min after returning to the supine position, DOC group demonstrated a significant decrease in log nHF (p < 0.01) and increases in log LF/HF (p < 0.01) and had lower log LF (p < 0.01) and log nLF (p < 0.05) compared to controls. In contrast, the control group exhibited a significant decrease in log nHF (p < 0.05) and increase in log LF/HF (p < 0.05) throughout the entire HUT test. Notably, no significant differences were observed when comparing time-domain outcomes reflecting parasympathetic nervous system between the two groups. HRV during HUT test indicated a delayed and attenuated autonomic response, particularly in the sympathetic nervous system, in DOC patients compared with healthy individuals.


Assuntos
Transtornos da Consciência , Sistema Nervoso Simpático , Humanos , Frequência Cardíaca/fisiologia , Teste da Mesa Inclinada , Sistema Nervoso Autônomo/fisiologia
13.
Neuroscience ; 546: 143-156, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38574798

RESUMO

Identifying the neural correlates of consciousness (NCCs) is an important way to understand the fundamental nature of consciousness. By recording event-related potentials (ERPs) using EEG, researchers have found three potential electrophysiological NCCs: early positive correlate of consciousness (enhanced P1), visual awareness negativity (VAN), and late positivity (LP). However, LP may reflect post-perceptual processing associated with subjective reports rather than consciousness per se. The present experiment investigated the relationship between LP and subjective reports. We adopted two subjective reporting tasks that differed in the requirement for subjective reports. In the low-frequency reporting task, participants needed to report whether they saw the target picture in 25% of trials, whereas in the high-frequency reporting task, participants needed to report whether they saw the target picture in each trial. Behavioral results showed that the hit rates were lower and false alarm rates were higher on reporting trials in low-frequency reporting tasks than on reporting trials in high-frequency reporting tasks. Unexpectedly, VAN was larger on reporting trials in the low-frequency reporting task than on reporting trials in the high-frequency reporting task. Importantly, our ERP results showed that LP was larger on reporting trials in the high-frequency reporting task than on reporting trials in the low-frequency reporting task. Thus, our findings indicated that when the frequency of reports was increased, the task relevance of the stimuli increased, which led to larger LP amplitudes. These findings suggest that LP correlates with subjective reports.

14.
Neurosci Biobehav Rev ; 161: 105670, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615851

RESUMO

Consciousness science is marred by disparate constructs and methodologies, making it challenging to systematically compare theories. This foundational crisis casts doubts on the scientific character of the field itself. Addressing it, we propose a framework for systematically comparing consciousness theories by introducing a novel inter-theory classification interface, the Measure Centrality Index (MCI). Recognizing its gradient distribution, the MCI assesses the degree of importance a specific empirical measure has for a given consciousness theory. We apply the MCI to probe how the empirical measures of the Global Neuronal Workspace Theory (GNW), Integrated Information Theory (IIT), and Temporospatial Theory of Consciousness (TTC) would fare within the context of the other two. We demonstrate that direct comparison of IIT, GNW, and TTC is meaningful and valid for some measures like Lempel-Ziv Complexity (LZC), Autocorrelation Window (ACW), and possibly Mutual Information (MI). In contrast, it is problematic for others like the anatomical and physiological neural correlates of consciousness (NCC) due to their MCI-based differential weightings within the structure of the theories. In sum, we introduce and provide proof-of-principle of a novel systematic method for direct inter-theory empirical comparisons, thereby addressing isolated evolution of theories and confirmatory bias issues in the state-of-the-art neuroscience of consciousness.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38573407

RESUMO

This article explores the profound impact of visualism and visual perception in the context of medical imaging diagnostics. It emphasizes the intricate interplay among vision, embodiment, subjectivity, language, and historicity within the realm of medical science and technology, with a specific focus on image consciousness. The study delves into the role of subjectivity in perception, facilitating the communication of opacity and historicity to the perceiving individual. Additionally, it scrutinizes the image interpretation process, drawing parallels to text interpretation and highlighting the influence of personal biases and individuality in medical practice. By revisiting Husserl's conceptualization of "image consciousness" and introducing the notion of "image theme", the paper seeks to establish a theoretical framework for making sense of images within the context of technological interpretation. A key objective is to enhance the phenomenology of technology through a systematic analysis of medical imaging diagnosis, contributing to an expanded epistemological foundation for medical practice. The article recognizes that the construction of medical knowledge incorporates subjective elements, especially within a historical context. The interpretation of images involves both instrumental and expert interpretation, with human subjectivity playing a crucial role. The article asserts that human creativity and conscious engagement are indispensable in interpreting all medical images.

16.
Front Psychol ; 15: 1360699, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577120

RESUMO

Inner speech is commonly understood as the conscious experience of a voice within the mind. One recurrent theme in the scientific literature is that the phenomenon involves a representation of overt speech, for example, a representation of phonetic properties that result from a copy of speech instructions that were ultimately suppressed. I propose a larger picture that involves some embodied objects and their misperception. I call it "the Body Error Theory," or BET for short. BET is a form of illusionism, but the particular version I favor is a cross-modal illusion. Newly described here, my hypothesis is that the experience of inner speech arises from a mix of interoception and audition. Specifically, there is the detection of slight but well-confirmed activities in the speech musculature that occur during inner speech, which helps to transform representations of normal but quiet nonverbal sounds that inevitably occur during inner speech, from breathing to background noise, into a mistaken perception of inner speech. Simply put, activities in the speech musculature mix with sounds to create the appearance of speech sounds, which thus explains the "voice within the mind." I also show how BET's cross-modal system fits with standard information processing accounts for speech monitoring and how it accommodates the central insights of leading theories of inner speech. In addition, I show how BET is supported by data from experience-sampling surveys and how it can be empirically tested against its rivals.

17.
Front Psychol ; 15: 1283980, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577121

RESUMO

Consciousness has intrigued philosophers and scholars for millennia and has been the topic of considerable scientific investigation in recent decades. Despite its importance, there is no unifying definition of the term, nor are there widely accepted measures of consciousness. Indeed, it is likely that consciousness-by its very nature-eludes measurement. It is, however, possible to measure how consciousness manifests as a lived experience. Yet here, too, holistic measures are lacking. This investigation describes the development and validation of the Awareness Atlas, a measure of the manifestation of consciousness. The scale was informed by heart-based contemplative practices and the resulting lived experience with a focus on the impacts of manifestation of consciousness on daily life. Four hundred forty-nine individuals from the USA, Canada, India, and Europe participated in psychometric testing of the scale. Exploratory and confirmatory factor analyses were used for validation, demonstrating excellent validity in measuring manifestation of consciousness. The final model fit exceeded all required thresholds, indicating an excellent fitted model with a single dimensionality to measure the manifestation of consciousness comprised of four subscales: Relationship to Others; Listening to the Heart; Connection with Higher Self; and Acceptance and Letting Go. Number of years meditating and practicing Heartfulness meditation were positively related to the total and subscale scores. Test-retest reliability was excellent for the total scale, and good to excellent for the four subscales. Findings demonstrate that the Awareness Atlas is a well-constructed tool that will be useful in examining changes in manifestation of consciousness with various experiences (e.g., meditation, life-altering conditions).

18.
Heliyon ; 10(7): e28421, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38623251

RESUMO

This behavioral study was undertaken to provide empirical evidence in favor of or opposed to the notion that animals across a wide breadth of the animal kingdom have subjective (personal) experience that varies with their lifestyles, ecological constraints, or phylogeny. Twelve species representing two invertebrate phyla and six vertebrate classes were observed unobtrusively in 15-min episodes, during which three modes of behavior (volitional, interactive, and egocentric) were quantified according to the frequency, variety, and dynamism of each mode. Volitional behavior was the most prevalent and dynamic mode for nearly all species, largely without regard to phylogenetic position. Interactive behavior likewise varied inconsistently across the entire evolutionary spectrum. Egocentric behavior was concentrated among the avian and mammalian species, but evidence of it were observed in the invertebrate species as well. Diagrams of the matrix constructed from the three qualitative modes and three quantitative attributes for each mode provide a metaphorical representation of the unique experiential profile of each species. To the extent that these behavioral measures correlate with the nature of the animal's subjective experience, they support the growing view that phenomenology is heterogeneous, multimodal, and non-linear in extent across the animal kingdom.

19.
Front Netw Physiol ; 4: 1292388, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628469

RESUMO

Identity-differentiating self from external reality-and agency-being the author of one's acts-are generally considered intrinsic properties of awareness and looked at as mental constructs generated by consciousness. Here a different view is proposed. All physiological systems display complex time-dependent regulations to adapt or anticipate external changes. To interact with rapid changes, an animal needs a nervous system capable of modelling and predicting (not simply representing) it. Different algorithms must be employed to predict the momentary location of an object based on sensory information (received with a delay), or to design in advance and direct the trajectory of movement. Thus, the temporal dynamics of external events and action must be handled in differential ways, thereby generating the distinction between self and non-self ("identity") as an intrinsic computational construct in neuronal elaboration. Handling time is not what neurons are designed for. Neuronal circuits are based on parallel processing: each bit of information diverges on many neurons, each of which combines it with many other data. Spike firing reports the likelihood that the specific pattern the neuron is designed to respond to is present in the incoming data. This organization seems designed to process synchronous datasets. However, since neural networks can introduce delays in processing, time sequences can be transformed into simultaneous patterns and analysed as such. This way predictive algorithms can be implemented, and continually improved through neuronal plasticity. To successfully interact with the external reality, the nervous system must model and predict, but also differentially handle perceptual functions or motor activity, by putting in register information that becomes available at different time moments. Also, to learn through positive/negative reinforcement, modelling must establish a causal relation between motor control and its consequences: the contrast between phase lag in perception and phase lead (and control) in motor programming produces the emergence of identity (discerning self from surrounding) and agency (control on actions) as necessary computational constructs to model reality. This does not require any form of awareness. In a brain, capable of producing awareness, these constructs may evolve from mere computational requirements into mental (conscious) constructs.

20.
Neuron ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38653247

RESUMO

The study of consciousness has developed well-controlled, rigorous methods for manipulating and measuring consciousness. Yet, in the process, experimental paradigms grew farther away from everyday conscious and unconscious processes, which raises the concern of ecological validity. In this review, we suggest that the field can benefit from adopting a more ecological approach, akin to other fields of cognitive science. There, this approach challenged some existing hypotheses, yielded stronger effects, and enabled new research questions. We argue that such a move is critical for studying consciousness, where experimental paradigms tend to be artificial and small effect sizes are relatively prevalent. We identify three paths for doing so-changing the stimuli and experimental settings, changing the measures, and changing the research questions themselves-and review works that have already started implementing such approaches. While acknowledging the inherent challenges, we call for increasing ecological validity in consciousness studies.

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