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1.
J Vis Exp ; (206)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38738870

RESUMO

The interplay between the brain and the cardiovascular systems is garnering increased attention for its potential to advance our understanding of human physiology and improve health outcomes. However, the multimodal analysis of these signals is challenging due to the lack of guidelines, standardized signal processing and statistical tools, graphical user interfaces (GUIs), and automation for processing large datasets or increasing reproducibility. A further void exists in standardized EEG and heart-rate variability (HRV) feature extraction methods, undermining clinical diagnostics or the robustness of machine learning (ML) models. In response to these limitations, we introduce the BrainBeats toolbox. Implemented as an open-source EEGLAB plugin, BrainBeats integrates three main protocols: 1) Heartbeat-evoked potentials (HEP) and oscillations (HEO) for assessing time-locked brain-heart interplay at the millisecond accuracy; 2) EEG and HRV feature extraction for examining associations/differences between various brain and heart metrics or for building robust feature-based ML models; 3) Automated extraction of heart artifacts from EEG signals to remove any potential cardiovascular contamination while conducting EEG analysis. We provide a step-by-step tutorial for applying these three methods to an open-source dataset containing simultaneous 64-channel EEG, ECG, and PPG signals. Users can easily fine-tune parameters to tailor their unique research needs using the graphical user interface (GUI) or the command line. BrainBeats should make brain-heart interplay research more accessible and reproducible.


Assuntos
Eletroencefalografia , Frequência Cardíaca , Humanos , Eletroencefalografia/métodos , Frequência Cardíaca/fisiologia , Processamento de Sinais Assistido por Computador , Software , Encéfalo/fisiologia , Aprendizado de Máquina
2.
Explore (NY) ; 20(2): 239-247, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37709571

RESUMO

Some people claim to occasionally know who is calling them without using traditional means. Controlled experiments testing these claims report mixed results. We conducted a cross-sectional study of triads examining the accuracy of knowing who was calling using two randomly selected designs: 1) a web server randomly chose the caller before the callee's guess (telepathic/pre-selected trials), and 2) a web server randomly chose the caller after the callee's guess (precognitive/post-selected trials). We also performed exploratory multilevel mixed-effects logistic regressions on the relationship of genetic relationships, emotional closeness, communication frequency, and physical distance data with accuracy. A total of 177 participants completed at least one trial (105 "completers" completed all 12 trials). Accuracy was significantly above chance for the 210 completers telepathic/pre-selected trials (50.0% where the chance expectation was 33.3%, p<.001) but not the 630 completers precognitive/post-selected trials (31.9% where the chance expectation was 33.3%, p = .61). We discuss how these results favor the psi hypothesis, although conventional explanations cannot be completely excluded. Genetic relatedness significantly predicted accuracy in the regression model (Wald χ2 = 53.0, P < .001) for all trials. Compared to 0% genetic relatedness, the odds of accurately identifying the caller was 2.88 times (188%) higher for 25% genetic relatedness (Grandparent/Grandchild or Aunt/Uncle or Niece/Nephew or Half Sibling; ß = 1.06, z = 2.10, P = .04), but the other genetic relatedness levels were not significant. In addition, communication frequency was significant (ß = 0.006, z = 2.19, P = .03) but physical distance (ß = 0.0002, z = 1.56, P = .12) and emotional closeness (ß = 0.005, z = 1.87, P = .06) were not for all trials. To facilitate study recruitment and completion, unavoidable changes to the protocol were made during the study due to persistent recruitment difficulties, including changing inclusion/exclusion criteria, increasing total call attempts to participants, adjusting trial type randomization schema to ensure trial type balance, and participant compensation. Thus, future research will be needed to continue to improve the methodology and examine the mechanism by which people claim to know who is calling, as well as factors that may moderate the effects.


Assuntos
Previsões , Telefone , Humanos , Estudos Transversais
3.
Prog Brain Res ; 277: 29-61, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37301570

RESUMO

Trance is an altered state of consciousness characterized by alterations in cognition. In general, trance states induce mental silence (i.e., cognitive thought reduction), and mental silence can induce trance states. Conversely, mind-wandering is the mind's propensity to stray its attention away from the task at hand and toward content irrelevant to the current moment, and its main component is inner speech. Building on the previous literature on mental silence and trance states and incorporating inverse source reconstruction advances, the study's objectives were to evaluate differences between trance and mind-wandering states using: (1) electroencephalography (EEG) power spectra at the electrode level, (2) power spectra at the area level (source reconstructed signal), and (3) EEG functional connectivity between these areas (i.e., how they interact). The relationship between subjective trance depths ratings and whole-brain connectivity during trance was also evaluated. Spectral analyses revealed increased delta and theta power in the frontal region and increased gamma in the centro-parietal region during mind-wandering, whereas trance showed increased beta and gamma power in the frontal region. Power spectra at the area level and pairwise comparisons of the connectivity between these areas demonstrated no significant difference between the two states. However, subjective trance depth ratings were inversely correlated with whole-brain connectivity in all frequency bands (i.e., deeper trance is associated with less large-scale connectivity). Trance allows one to enter mentally silent states and explore their neurophenomenological processes. Limitations and future directions are discussed.


Assuntos
Atenção , Encéfalo , Humanos , Encéfalo/diagnóstico por imagem , Cognição , Mapeamento Encefálico , Eletroencefalografia
4.
Front Psychol ; 13: 955594, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36160593

RESUMO

The nature of consciousness is considered one of science's most perplexing and persistent mysteries. We all know the subjective experience of consciousness, but where does it arise? What is its purpose? What are its full capacities? The assumption within today's neuroscience is that all aspects of consciousness arise solely from interactions among neurons in the brain. However, the origin and mechanisms of qualia (i.e., subjective or phenomenological experience) are not understood. David Chalmers coined the term "the hard problem" to describe the difficulties in elucidating the origins of subjectivity from the point of view of reductive materialism. We propose that the hard problem arises because one or more assumptions within a materialistic worldview are either wrong or incomplete. If consciousness entails more than the activity of neurons, then we can contemplate new ways of thinking about the hard problem. This review examines phenomena that apparently contradict the notion that consciousness is exclusively dependent on brain activity, including phenomena where consciousness appears to extend beyond the physical brain and body in both space and time. The mechanisms underlying these "non-local" properties are vaguely suggestive of quantum entanglement in physics, but how such effects might manifest remains highly speculative. The existence of these non-local effects appears to support the proposal that post-materialistic models of consciousness may be required to break the conceptual impasse presented by the hard problem of consciousness.

5.
Front Hum Neurosci ; 15: 745135, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35002651

RESUMO

Electroencephalography (EEG) alpha asymmetry is thought to reflect crucial brain processes underlying executive control, motivation, and affect. It has been widely used in psychopathology and, more recently, in novel neuromodulation studies. However, inconsistencies remain in the field due to the lack of consensus in methodological approaches employed and the recurrent use of small samples. Wearable technologies ease the collection of large and diversified EEG datasets that better reflect the general population, allow longitudinal monitoring of individuals, and facilitate real-world experience sampling. We tested the feasibility of using a low-cost wearable headset to collect a relatively large EEG database (N = 230, 22-80 years old, 64.3% female), and an open-source automatic method to preprocess it. We then examined associations between well-being levels and the alpha center of gravity (CoG) as well as trait EEG asymmetries, in the frontal and temporoparietal (TP) areas. Robust linear regression models did not reveal an association between well-being and alpha (8-13 Hz) asymmetry in the frontal regions, nor with the CoG. However, well-being was associated with alpha asymmetry in the TP areas (i.e., corresponding to relatively less left than right TP cortical activity as well-being levels increased). This effect was driven by oscillatory activity in lower alpha frequencies (8-10.5 Hz), reinforcing the importance of dissociating sub-components of the alpha band when investigating alpha asymmetries. Age was correlated with both well-being and alpha asymmetry scores, but gender was not. Finally, EEG asymmetries in the other frequency bands were not associated with well-being, supporting the specific role of alpha asymmetries with the brain mechanisms underlying well-being levels. Interpretations, limitations, and recommendations for future studies are discussed. This paper presents novel methodological, experimental, and theoretical findings that help advance human neurophysiological monitoring techniques using wearable neurotechnologies and increase the feasibility of their implementation into real-world applications.

6.
Handb Clin Neurol ; 168: 207-232, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32164854

RESUMO

Brain-computer interfaces and wearable neurotechnologies are now used to measure real-time neural and physiologic signals from the human body and hold immense potential for advancements in medical diagnostics, prevention, and intervention. Given the future role that wearable neurotechnologies will likely serve in the health sector, a critical state-of-the-art assessment is necessary to gain a better understanding of their current strengths and limitations. In this chapter we present wearable electroencephalography systems that reflect groundbreaking innovations and improvements in real-time data collection and health monitoring. We focus on specifications reflecting technical advantages and disadvantages, discuss their use in fundamental and clinical research, their current applications, limitations, and future directions. While many methodological and ethical challenges remain, these systems host the potential to facilitate large-scale data collection far beyond the reach of traditional research laboratory settings.


Assuntos
Interfaces Cérebro-Computador , Encéfalo/fisiologia , Neurorretroalimentação/fisiologia , Autoavaliação (Psicologia) , Eletroencefalografia/métodos , Humanos , Dispositivos Eletrônicos Vestíveis
7.
F1000Res ; 8: 67, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30815253

RESUMO

Background: Numerous world cultures believe channeling provides genuine information, and channeling rituals in various forms are regularly conducted in both religious and non-religious contexts. Little is known about the physiological correlates of the subjective experience of channeling. Methods: We conducted a prospective within-subject design study with 13 healthy adult trance channels. Participants alternated between 5-minute blocks of channeling and no-channeling three times while electroencephalography (EEG), electrocardiography (ECG), galvanic skin response (GSR), and respiration were collected on two separate days. Voice recordings of the same story read in channeling and no-channeling states were also analyzed.   Results: The pre-laboratory survey data about demographics, perception of the source, purpose and utility of channeled information reflected previous reports. Most participants were aware of their experience (rather than in a full trance) and had varying levels of perceived incorporation (i.e. control of their body). Voice analysis showed an increase in voice arousal and power (dB/Hz) differences in the 125 Hz bins between 0 and 625 Hz, and 3625 and 3875 Hz when reading during the channeling state versus control. Despite subjective perceptions of distinctly different states, no substantive differences were seen in EEG frequency power, ECG measures, GSR and respiration. Conclusions: Voice parameters were different between channeling and no-channeling states using rigorous controlled methods, but other physiology measure collected were not. Considering the subjective and phenomenological differences observed, future studies should include other measures such as EEG connectivity analyses, fMRI and biomarkers.


Assuntos
Comportamento Ritualístico , Eletroencefalografia , Resposta Galvânica da Pele , Espiritualidade , Adulto , Eletrocardiografia , Feminino , Humanos , Masculino , Estudos Prospectivos
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