RESUMO
Ketamine is a dissociative anesthetic that induces a shift in global consciousness states and related brain dynamics. Portable low-density EEG systems could be used to monitor these effects. However, previous evidence is almost null and lacks adequate methods to address global dynamics with a small number of electrodes. This study delves into brain high-order interactions (HOI) to explore the effects of ketamine using portable EEG. In a double-blinded cross-over design, 30 male adults (mean age = 25.57, SD = 3.74) were administered racemic ketamine and compared against saline infusion as a control. Both task-driven (auditory oddball paradigm) and resting-state EEG were recorded. HOI were computed using advanced multivariate information theory tools, allowing us to quantify nonlinear statistical dependencies between all possible electrode combinations. Ketamine induced an increase in redundancy in brain dynamics (copies of the same information that can be retrieved from 3 or more electrodes), most significantly in the alpha frequency band. Redundancy was more evident during resting state, associated with a shift in conscious states towards more dissociative tendencies. Furthermore, in the task-driven context (auditory oddball), the impact of ketamine on redundancy was more significant for predictable (standard stimuli) compared to deviant ones. Finally, associations were observed between ketamine's HOI and experiences of derealization. Ketamine appears to increase redundancy and HOI across psychometric measures, suggesting these effects are correlated with alterations in consciousness towards dissociation. In comparisons with event-related potential (ERP) or standard functional connectivity metrics, HOI represent an innovative method to combine all signal spatial interactions obtained from low-density dry EEG in drug interventions, as it is the only approach that exploits all possible combinations between electrodes. This research emphasizes the potential of complexity measures coupled with portable EEG devices in monitoring shifts in consciousness, especially when paired with low-density configurations, paving the way for better understanding and monitoring of pharmacological-induced changes.
Assuntos
Encéfalo , Estudos Cross-Over , Eletroencefalografia , Ketamina , Humanos , Ketamina/farmacologia , Masculino , Adulto , Método Duplo-Cego , Adulto Jovem , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Anestésicos Dissociativos/farmacologia , Anestésicos Dissociativos/administração & dosagem , Descanso , Estado de Consciência/efeitos dos fármacos , Estado de Consciência/fisiologiaRESUMO
Consciousness is one of the most complex aspects of human experience. Studying the mechanisms involved in the transitions among different levels of consciousness remains as one of the greatest challenges in neuroscience. In this study we use a measure of integrated information (ΦAR) to evaluate dynamic changes during consciousness transitions. We applied the measure to intracranial electroencephalography (SEEG) recordings collected from 6 patients that suffer from refractory epilepsy, taking into account inter-ictal, pre-ictal and ictal periods. We analyzed the dynamical evolution of ΦAR in groups of electrode contacts outside the epileptogenic region and compared it with the Consciousness Seizure Scale (CCS). We show that changes on ΦAR are significantly correlated with changes in the reported states of consciousness.
Assuntos
Epilepsia , Cristalino , Unionidae , Humanos , Animais , Estado de Consciência , Teoria da Informação , ConvulsõesRESUMO
Self-awareness, the ability to take oneself as the object of awareness, has been an enigma for our species, with different answers to this question being provided by religion, philosophy, and, more recently, science. The current review aims to discuss the neurocognitive mechanisms underlying self-awareness. The multidimensional nature of self-awareness will be explored, suggesting how it can be thought of as an emergent property observed in different cognitive complexity levels, within a predictive coding approach. A presentation of alterations of self-awareness in neuropsychiatric conditions will ground a discussion on alternative frameworks to understand this phenomenon, in health and psychopathology, with future research directions being indicated to fill current gaps in the literature. This article is categorized under: Philosophy > Consciousness Psychology > Brain Function and Dysfunction Neuroscience > Cognition.
Assuntos
Neurociência Cognitiva , Neurociências , Humanos , Cognição , Estado de Consciência , Percepção , ConscientizaçãoRESUMO
A prática de mindfulness tornou-se um tema relevante devido às evidências de sua eficácia para o tratamento de muitas condições de saúde, especialmente as de saúde mental, que suscitaram o interesse de clientes e psicoterapeutas quanto a sua aplicação clínica. No entanto, não há dados sobre o conhecimento de mindfulness por parte de psicólogos clínicos, o que afeta diretamente a habilidade de utilizar ou recomendar práticas baseadas na. Este estudo, de levantamento descritivo, exploratório e transversal, buscou caracterizar o conhecimento sobre mindfulness descrito por psicólogos clínicos brasileiros. Participaram do estudo 417 psicólogos de diferentes abordagens e estados brasileiros, que responderam a um questionário online. Dados quantitativos foram analisados por frequências, proporções e teste qui-quadrado. Para dados qualitativos, utilizou-se o método de classificação hierárquica descendente. Dessa maneira, foram identificadas cinco classes de descrição de mindfulness: ausência de conhecimento, efeitos, abordagem terapêutica, técnicas e definição operacional. Concluiu-se que os resultados refletem a necessidade de integrar o tema na formação acadêmica em psicologia, capacitando mais o psicólogo para fornecer adequadamente ao cliente informações, recomendações ou aplicação de mindfulness no contexto da prática clínica.(AU)
The practice of mindfulness has become a relevant topic due to the evidence of its effectiveness for treating many health conditions, especially those of mental health, which aroused the interest of clients and psychotherapists regarding its clinical application. However, there is no data on the knowledge that clinical psychologists have about mindfulness, which directly affects their ability to use or recommend practices based on the technique. This descriptive, exploratory, and cross-sectional study aimed to characterize the knowledge about mindfulness described by Brazilian clinical psychologists. A total of 417 psychologists from different approaches and Brazilian states, which answered an online questionnaire, participated in the study. Quantitative data were analyzed by frequencies, proportions, and chi-square test. For qualitative data, the descending hierarchical classification method was used. Thus, five classes of mindfulness description were identified: lack of knowledge, effects, therapeutic approach, techniques, and operational definition. In conclusion, the results reflect the need to integrate the theme in professional training in psychology, better training the psychologist to adequately provide the client with information, recommendations, or application of mindfulness in the context of clinical practice.(AU)
La práctica de atención plena ha cobrado relevancia debido a la evidencia de efectividad para muchas afecciones de salud, sobre todo de salud mental, la cual despertó el interés de clientes y psicoterapeutas con respecto a su aplicación clínica. Sin embargo, no existen datos sobre el conocimiento que tienen los psicólogos clínicos sobre la atención plena, lo que incide directamente en la capacidad de utilizar o recomendar prácticas basadas en esta práctica en el contexto clínico. Este estudio descriptivo, exploratorio y transversal tuvo como objetivo caracterizar el conocimiento sobre atención plena descrito por psicólogos clínicos brasileños. En este estudio participaron 417 psicólogos de diferentes enfoques y estados brasileños quienes respondieron un cuestionario en línea. Los datos cuantitativos se analizaron por frecuencias, proporciones y prueba de chi-cuadrado. Para los datos cualitativos se utilizó el método de clasificación jerárquica descendente. Como resultado, se identificaron cinco clases de descripción de atención plena: falta de conocimiento, efectos, enfoque terapéutico, técnicas y definición operativa. Se concluye que los resultados muestran la necesidad de integrar el tema en la formación académica en psicología, ofreciendo más capacitación al psicólogo para proporcionar al cliente información, recomendaciones o aplicación de la atención plena en el contexto de la práctica clínica.(AU)
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Prática Profissional , Psicologia , Conhecimento , Atenção Plena , Ansiedade , Percepção , Psicologia Clínica , Psicoterapia , Qualidade de Vida , Relaxamento , Respiração , Estresse Psicológico , Pensamento , Comportamento , Budismo , Humanos , Terapia Cognitivo-Comportamental , Oxigenação , Saúde Mental , Inquéritos e Questionários , Cognição , Consciência , Estado de Consciência , Meditação , Relações Metafísicas Mente-Corpo , Terapias Mente-Corpo , Emoções , Existencialismo , Comportamento Exploratório , Terapia de Aceitação e Compromisso , Autocontrole , Angústia PsicológicaRESUMO
Ayahuasca is a brew with psychoactive properties that has been used as an entheogen for centuries, with more recent studies suggesting it is a promising treatment for some clinical disorders. Although there is an emerging scientific literature on its effects, to the best of our knowledge no study has explored the self-reported experiences of first-time ayahuasca users with quantitative textual analysis tools. Accordingly, the current study aimed to analyze the subjective experience of naive individuals with depression and healthy controls after consuming ayahuasca. For this purpose, responses from a subsample of participants from a previous clinical trial to open-ended questions regarding their experience with ayahuasca underwent textual analysis. Data from nine patients with treatment-resistant depression and 20 healthy individuals were included, and quantitative textual analysis was performed using IRaMuTeQ 0.7 alpha 2 and R 3.1.2. The analysis identified five clusters: alterations in the state of consciousness, cognitive changes, somatic alterations, auditory experiences, and visual perceptual content. Additionally, findings suggest specific features of the experience of people with depression with ayahuasca, such as increased aversive bodily reactions. The results are consistent with previous findings indicating central axes of the psychedelic experience, and may inform therapeutic approaches using ayahuasca.
Assuntos
Banisteriopsis , Alucinógenos , Humanos , Depressão/tratamento farmacológico , Alucinógenos/farmacologia , Alucinógenos/uso terapêutico , Estado de Consciência , AfetoRESUMO
Dreaming is a complex phenomenon that occurs during sleep, involving various conscious dream experiences. Lucid dreams (LDs) involve heightened awareness within the dream environment, while out-of-body experiences (OBEs) involve the sensation of being outside one's physical body. OBEs occur during sleep paralysis (SP), where voluntary movements are inhibited during sleep/wake transitions while remaining aware of the surroundings. The relationship between LDs and OBEs is debated, with some viewing them as distinct phenomena and others considering them different manifestations of the same underlying experience. This study aimed to characterize non-lucid dreams, LDs, and OBEs by analyzing dream reports' structural properties. OBE reports displayed a condensed and interconnected network structure compared to non-lucid dreams and LDs. Additionally, OBE reports exhibited a specialized network structure, with specific nodes playing a more central role. These findings suggest that OBE dreams may have a more coherent and unified narrative, with certain nodes being pivotal in the network structure.
Assuntos
Conscientização , Sono REM , Sonhos , Sono , Estado de ConsciênciaRESUMO
Sugar, salt, and fat content in processed products are important concerns for consumers. Hence, alternative "healthy" versions of conventional foods such as chocolate, potato chips, and yogurt are offered. This work aimed to define the emotional response of consumers from different cultural backgrounds (Spain vs. Brazil) evoked by healthier versions of conventional products and the relationship between hedonic responses and health consciousness. A total of 186 Brazilian and 152 Spanish consumers participated in this online cross-cultural study. Participants answered a Health Consciousness Questionnaire and an emotional check-all-that-applies questionnaire using picture stimuli of conventional chocolate, potato chips, and yogurt and their healthier versions with less sugar, salt, and fat content, respectively. The Brazilians' emotional responses were more diverse for all stimuli compared to the Spaniards'. However, participants from both cultures rated an average of "slightly agree" on the health consciousness scale; a higher level of consumption, liking, and willingness to buy; and a higher frequency of positive emotional terms for the stimuli of conventional products compared to their healthier versions. A higher frequency of evocation of "active" is strongly associated with higher levels of health consciousness. Strategic actions by the food industry and government must consider cultural, emotional, and health-conscious factors to encourage the consumption of healthier foods. PRACTICAL APPLICATION: Food manufacturers can use the information obtained from this study to create healthier versions of their products that appeal to consumers' emotional responses and health consciousness levels. The findings can assist in designing strategic actions to promote healthier food consumption by emphasizing the benefits of healthier food choices and making them more appealing to consumers. The methodology employed in this study can also be applied to further studies aimed to assess emotional responses to food stimuli across different cultures.
Assuntos
Emoções , Preferências Alimentares , Alimentos Especializados , Humanos , Cacau , Estado de Consciência , Comportamento do Consumidor , Cloreto de Sódio na Dieta , Dieta Saudável , Açúcares da DietaRESUMO
Neonatal hypoxic ischemic encephalopathy (HIE) is a type of injury caused by lack of oxygen in the brain during the neonatal period. It is a clinical syndrome clearly recognizable in term and premature newborns secondary to asphyxia at the time of delivery. HIE is estimated to occur at a frequency of 1-3 for each 1000 alive newborns per year in developed countries. In countries of low or medium income, the incidence is up to 10-20 times higher, equivalent to 1-8 alive newborns per each 1000. The social and economic impact has been estimated near US$ 50.2 million per year of life adjusted to disability. At the same time, it is estimated in 7, the number of patients needed to treat with corporal cooling therapy (CCT)to prevent one case of death or severe disability. The etiology is multifactorial and includes prenatal, perinatal and postnatal factors. The diagnosis is based in the inability to support spontaneous breath at the time of delivery requiring assisted ventilation, Apgar less than 5 at 5 and 10 minutes, altered level of consciousness, neonatal reflexes and muscle tone. This article is a review of the stablished and emergent therapeutic strategies based on the pathophysiological disease process.
La encefalopatía hipóxica isquémica del neonato (EIH) es un tipo de injuria causada por la falta de oxígeno en el cerebro durante el periodo neonatal. Es un síndrome clínico claramente reconocible en recién nacidos a término y prematuros debido a asfixia fetal en el momento del nacimiento. Se estima que EHI ocurre a una frecuencia de1 a 3 por cada 1000 nacimientos vivos al año en países desarrollados. En países de bajo o mediano ingreso, la incidencia es hasta 10-20 veces más alta, equivalente a 1-8 nacidos vivos por cada 1000. El impacto social y económico ha sido estimado en cerca de 50.2 millones de dólares por año de vida ajustados a discapacidad. Así mismo, se estima que 7 es el número necesario de pacientes a tratar con hipotermia corporal terapéutica (HCT) para evitar un caso de muerte o minusvalía severa. La etiología es multifactorial e incluye factores prenatales, perinatales o post natales. El diagnóstico se basa en la incapacidad para respirar en el momento del nacimiento requiriendo ventilación asistida, Apgar menos de 5 a los 5 y 10 minutos, alteración del estado normal de conciencia, reflejos neonatales y de tono muscular. Este artículo revisa los avances y estrategias terapéuticas establecidas y emergentes basadas en las fases pato-fisiológicas de este proceso.
Assuntos
Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Recém-Nascido , Feminino , Gravidez , Humanos , Hipóxia-Isquemia Encefálica/etiologia , Hipóxia-Isquemia Encefálica/terapia , Encéfalo , Estado de ConsciênciaRESUMO
In human and nonhuman primates, deep brain stimulation applied at or near the internal medullary lamina of the thalamus [a region referred to as "central thalamus," (CT)], but not at nearby thalamic sites, elicits major changes in the level of consciousness, even in some minimally conscious brain-damaged patients. The mechanisms behind these effects remain mysterious, as the connections of CT had not been specifically mapped in primates. In marmoset monkeys (Callithrix jacchus) of both sexes, we labeled the axons originating from each of the various CT neuronal populations and analyzed their arborization patterns in the cerebral cortex and striatum. We report that, together, these CT populations innervate an array of high-level frontal, posterior parietal, and cingulate cortical areas. Some populations simultaneously target the frontal, parietal, and cingulate cortices, while others predominantly target the dorsal striatum. Our data indicate that CT stimulation can simultaneously engage a heterogeneous set of projection systems that, together, target the key nodes of the attention, executive control, and working-memory networks of the brain. Increased functional connectivity in these networks has been previously described as a signature of consciousness.SIGNIFICANCE STATEMENT In human and nonhuman primates, deep brain stimulation at a specific site near the internal medullary lamina of the thalamus ["central thalamus," (CT)] had been shown to restore arousal and awareness in anesthetized animals, as well as in some brain-damaged patients. The mechanisms behind these effects remain mysterious, as CT connections remain poorly defined in primates. In marmoset monkeys, we mapped with sensitive axon-labeling methods the pathways originated from CT. Our data indicate that stimulation applied in CT can simultaneously engage a heterogeneous set of projection systems that, together, target several key nodes of the attention, executive control, and working-memory networks of the brain. Increased functional connectivity in these networks has been previously described as a signature of consciousness.
Assuntos
Lesões Encefálicas , Callithrix , Masculino , Animais , Feminino , Humanos , Tálamo/fisiologia , Córtex Cerebral/fisiologia , Nível de Alerta/fisiologia , Estado de Consciência/fisiologia , Vias Neurais/fisiologiaRESUMO
The Society for Psychical Research (SPR) of London was founded in 1882 with the purpose of investigating psychical phenomena, especially the theme of survival, with scientific rigour. Despite the recognized importance of the SPR for dynamic psychiatry in the nineteenth and twentieth centuries, there are few studies of its epistemological contributions to the theme of survival and its implications to science. In order to fill this gap, we have consulted the main journals of the SPR in its golden period, and highlight the epistemologies of Sidgwick, Myers, James, Podmore, Schiller, Lodge and Richet. We conclude that the authors, whether for or against survival, argued in defence of an expanded science, and looked forward to understanding the complexity of human experience.