EEG

Article in Dutch about the unfounded upheaval surrounding the paper "Electroencephalographic Recordings during Withdrawal of Life-Sustaining Therapy until 30 Minutes after Declaration of Death"  by Loretta Norton et al., of 2017. Published in Terugkeer naar Levenslicht, Vol. 1, Nr. 1/2, Spring/Summer 2017, pp. 32-33.

Within the framework of a M.Sc. Neurosciences Master’s thesis, the present study assessed context-dependent memory (CDM) reactivation in the waking state and oscillatory activity in the brain during music listening at rest. CDM reactivation is a phenomenon with which memory consolidation can be experimentally manipulated by repeating the context in which memories were initially created. Music has been shown to be sufficient for the effects of context-dependent memory, but experimental reactivation using music as a context has not yet been shown. Further, many students use background music as a study aid, and it is therefore relevant to research in memory, cognition, and education. The present study investigated oscillatory activity in the brain during music listening at rest, specifically in the alpha (8-12 Hz) and beta (15-30 Hz) ranges. After performing a non-spatial face memory task with background music (Chopin’s Nocturnes), memory traces were manipulated through repeating context in a waking-state consolidation phase. Testing immediately following the consolidation phase demonstrated no effect of repeating context on performance, suggesting that CDM reactivation does not work during wakefulness. This is in line with many other studies, but should further be investigated during slow-wave sleep to determine the usefulness of music as context on CDM reactivation as a whole. Further, the condition in which there was no music during consolidatiion exhibited lower power in the alpha (8-12 Hz) range compared to the music conditions. This is in line with previous research and supports the idea of alpha activity representing cortical inhibition. Moreover, alpha activity was localized to the occipital electrodes, suggesting localization to the visual cortex. No effect of condition was found on beta power, but it was found to be higher over temporal and temporoparietal electrodes, suggesting localization to temporal cortical areas, including auditory cortex. The results presented here clarify some discrepancies in previously published literature, but the question remains of the effectiveness of CDM reactivation in wakefulness and of the nature of oscillatory neural activity during music listening and its functional effects on memory task performance.

Recent years have seen huge advancements in the methods available and used in neuroscience employing EEG or MEG. However, the standard approach is to average a large number of trials for experimentally defined conditions in order to reduce intertrial-variability, i.e. treating it as a source of "noise". Yet it is now more and more accepted that trial-to-trial fluctuations bear functional significance, reflecting fluctuations of "brain states" that predispose perception and action. Such effects are often revealed in a pre-stimulus period, when comparing response variability to an invariant stimulus. However such offline analyses are disadvantageous as they are correlational by drawing conclusions in a posthoc-manner and stimulus presentation is random with respect to the feature of interest. A more direct test is to trigger stimulus presentation when the relevant feature is present. The current paper introduces ConSole (CONstance System for OnLine Eeg), a software...

Introduction: “Sajdah”, a prostration position, is part of Muslim daily prayers. It seems
to have several effects on the brain and heart function. This study aimed to investigate the
prefrontal brain activity after 10 seconds of Sajdah in the direction of Qibla (the direction that
a Muslim prays) while putting the forehead on the ground.
Methods: Three women and two men participated in this pilot study. Linear (absolute and
relative power of θ (4-8Hz), α 1 (8-10 Hz), α 2 (10-12 Hz), β 1 (12-16 Hz), β 2 (16-20 Hz), β 3
(20-30 Hz), γ 1 (30-40 Hz), γ 2 (40-50 Hz) and non-linear features (approximate entropy, Katz
fractal dimension, Petrosian fractal dimension, spectral entropy, and sample entropy) from Fps
channel were calculated.
Results: The relative β to γ band, approximate and sample entropy, Petrosian fractal dimension
and mean of amplitude decreased in open eye state in women. While θ to γ bands in the closed
eye state decreased after Sajdah in women. The absolute γ bands in closed eye state and relative
β band in open eye state increased after Sajdah in men.
Conclusion: The pilot study showed that 10 seconds of Sajdah has effects on brain activity and
sometimes showed the opposite effect on genders.

Auditory novelty detection has been associated with different cognitive processes. Bekinschtein et al. (2009) developed an experimental paradigm to dissociate these processes, using local and global novelty, which were associated, respectively, with automatic versus strategic perceptual processing. They have mostly been studied using event-related potentials (ERPs), but local spiking activity as indexed by gamma (60-120 Hz) power and interactions between brain regions as indexed by modulations in beta-band (13-25 Hz) power and functional connectivity have not been explored. We thus recorded 9 epileptic patients with intracranial electrodes to compare the precise dynamics of the responses to local and global novelty. Local novelty triggered an early response observed as an intracranial mismatch negativity (MMN) contemporary with a strong power increase in the gamma band and an increase in connectivity in the beta band. Importantly, all these responses were strictly confined to the te...

As the power of modern computers grows alongside our understanding of the human brain, we move a step closer in transforming some pretty spectacular science fiction into reality. The advent of Brain Computer Interface (BCI) is indeed leading us to a burgeoning era of complete automation empowering our interaction with computer not only with robustness but with also a gift of intelligence. For the fraction of our society suffering from severe motor disabilities BCI has offered a novel solution of overcoming the problems faced in communicating and environment control. Thus the purpose of our current research is to harness the brain‟s ability to generate Visually Evoked Potentials (VEPs) by capturing the response of the brain to the transitions of color from grey to green and grey to red. Our prime focus is to explore EEG-based signal processing techniques in order to classify two colors; which can be further deployed in future by coupling the actuators so as to perform few basic tasks...

In neuronal recording studies on anesthetized animals, reliable measures for the transitional moment of consciousness are frequently required. Previous findings suggest that pupil fluctuations reflect the neuronal states during quiet wakefulness, whose correlation was unknown for the anesthetized condition. Here, we investigated the pupillary changes under isoflurane anesthesia simultaneously with the electroencephalogram (EEG) and electromyogram (EMG). The pupil was tracked by using a region-based active contour model. The dose was given to the animal in a stepwise increasing mode (simulating induction of anesthesia) or in a stepwise decreasing mode (simulating emergence of anesthesia). We found that the quickly widening pupil action (mydriasis) characterizes the transitional state in anesthesia. Mydriasis occurred only in the light dose in the emergence phase, and the events                                                                                                                                    suggest that recording such pupil changes may offer a noncontact monitoring tool for indexing the transitional state of the brain, particularly when a lower threshold dose is applied.

New treatments for Alzheimer's disease require early detection of cognitive decline. Most studies seeking to identify markers of early cognitive decline have focused on a limited number of measures. We sought to establish the profile of brain function measures which best define early neuropsychological decline. We compared subjects with subjective memory complaints to normative controls on a wide range of EEG derived measures, including a new measure of event-related spatio-temporal waves and biophysical modeling, which derives anatomical and physiological parameters based on subject's EEG measurements. Measures that distinguished the groups were then related to cognitive performance on a variety of learning and executive function tasks. The EEG measures include standard power measures, peak alpha frequency, EEG desynchronization to eyes-opening, and global phase synchrony. The most prominent differences in subjective memory complaint subjects were elevated alpha power and an increased number of spatio-temporal wave events. Higher alpha power and changes in wave activity related most strongly to a decline in verbal memory performance in subjects with subjective memory complaints, and also declines in maze performance and working memory reaction time. Interestingly, higher alpha power and wave activity were correlated with improved performance in reverse digit span in the subjective memory complaint group. The modeling results suggest that differences in the subjective memory complaint subjects were due to a decrease in cortical and thalamic inhibitory gains and slowed dendritic time-constants. The complementary profile that emerges from the variety of measures and analyses points to a nonlinear progression in electrophysiological changes from early neuropsychological decline to late-stage dementia, and electrophysiological changes in subjective memory complaint that vary in their relationships to a range of memory-related tasks.

Keywords: Subjective memory complaint; cognition; EEG; Traveling waves; Biophysical model; Neural synchrony; International database

SUMMARY  The dynamics of the sleep EEG were investigated by all-night spectral analysis of 51 sleep records. Power density was calculated for 1-Hz bins in the 0.25–25.0 Hz range. Values in non-rapid-eye-movement sleep (NREMS) were higher than in REMS in the 0.25–16.0 Hz range, and lower in the 18.25–22.0 Hz range. Power density in the 0.25–12.0 Hz range showed a declining trend over the first four NREMS episodes, which, depending on the frequency bin, could be approximated by non-linear or linear decay functions. In the frequency range of sleep spindles (12.25–15.0 Hz), power density in the 13.25–15.0 Hz band showed an increasing trend between NREMS episode 2 and NREMS episode 4. A correlation matrix of 25 1-Hz bins revealed for NREMS a negative correlation between slow-wave activity (SWA; 0.25–4.0 Hz) and activity in the spindle frequency range. This negative correlation was highest in the first NREMS episode and diminished progressively over the subsequent NREMS episodes. Within NREMS episodes, the values in the spindle frequency range showed a U-shaped time course, the trough coinciding with a high level of SWA. By contrast, in both the early and late part of the episode the two types of activity changed in the same direction. The results are consistent with recent electrophysiological studies indicating that the establishment of NREMS is associated with a progressive hyperpolarization of thalamocortical neurons during which the membrane potential exhibits oscillations first in the spindle frequency range and then in the range of SWA.

A better understanding of observable and quantifiable psychophysiological outputs such as electroencephalography (EEG) during computer video gameplay has significant potential to support the development of an automated, emotionally intelligent system. Integrated into a game engine, such a system could facilitate an effective biofeedback loop, accurately interpreting player emotions and adjusting gameplay parameters to respond to players’ emotional states in a way that moves towards exciting ventures in affective interactivity. This paper presents a crucial step to reaching this objective by way of examining the statistical features of EEG that may relate to user experience during audio-centric gameplay. An audio-only test game ensures that game sound is the exclusive stimulus modality with gameplay contextualisation and qualitative data collection enabling the study to focus specifically upon fear. Though requiring of an unambiguous horror-game context, the results documented within this paper identify several statistical features of EEG data that could differentiate fear from calm.

The use of neuroscience tools to study consumer behavior and the decision making process in marketing has improved our understanding of cognitive, neuronal, and emotional mechanisms related to marketing-relevant behavior. However, knowledge about neuroscience tools that are used in consumer neuroscience research is scattered. In this article, we present the results of a literature review that aims to provide an overview of the available consumer neuroscience tools and classifies them according to their characteristics. We analyse a total of 219 full-texts in the area of consumer neuroscience. Our findings suggest that there are seven tools that are currently used in consumer neuroscience research. In particular, electroencephalography (EEG) and eye tracking (ET) are the most commonly used tools in the field. We also find that consumer neuroscience tools are used to study consumer preferences and behaviors in different marketing domains such as advertising, branding, online experienc...

The current review addresses emerging issues that arise from the creation of safe, beneficial, and trusted artificial intelligence–air traffic controller (AI-ATCO) systems for air traffic management (ATM). These issues concern trust between the human user and automated or AI tools of interest, resilience, safety, and transparency. To tackle these issues, we advocate the development of practical AI-ATCO teaming frameworks by bringing together concepts and theories from neuroscience and explainable AI (XAI). By pooling together knowledge from both ATCO and AI perspectives, we seek to establish confidence in AI-enabled technologies for ATCOs. In this review, we present an overview of the extant studies that shed light on the research and development of trusted human-AI systems, and discuss the prospects of extending such works to building better trusted ATCO-AI systems. This paper contains three sections elucidating trust-related human performance, AI and explainable AI (XAI), and human-AI teaming. [COPYRIGHT CC BY-NC-ND 4.0, J. Y. ZHONG 2021, NANYANG TECHNOLOGICAL UNIVERSITY]

Despite the widely documented influence of gender stereotypes on social behaviour, little is known about the
electrophysiological substrates engaged in the processing of such information when conveyed by language. Using eventrelated brain potentials (ERPs), we examined the brain response to third-person pronouns (lei ‘‘she’’ and lui ‘‘he’’) that were implicitly primed by definitional (passeggeraFEM ‘‘passenger’’, pensionatoMASC ‘‘pensioner’’), or stereotypical antecedents (insegnante ‘‘teacher’’, conducente ‘‘driver’’). An N400-like effect on the pronoun emerged when it was preceded by a definitionally incongruent prime (passeggeraFEM – lui; pensionatoMASC – lei), and a stereotypically incongruent prime for masculine pronouns only (insegnante – lui). In addition, a P300-like effect was found when the pronoun was preceded by
definitionally incongruent primes. However, this effect was observed for female, but not male participants. Overall, these
results provide further evidence for on-line effects of stereotypical gender in language comprehension. Importantly, our results also suggest a gender stereotype asymmetry in that male and female stereotypes affected the processing of
pronouns differently.

In speech communication, listeners must accurately decode vocal cues that refer to the speaker's mental state, such as their confidence or 'feeling of knowing'. However, the time course and neural mechanisms associated with online inferences about speaker confidence are unclear. Here, we used event-related potentials (ERPs) to examine the temporal neural dynamics underlying a listener's ability to infer speaker confidence from vocal cues during speech processing. We recorded listeners' real-time brain responses while they evaluated statements wherein the speaker's tone of voice conveyed one of three levels of confidence (confident, close-to-confident, unconfident) or were spoken in a neutral manner. Neural responses time-locked to event onset show that the perceived level of speaker confidence could be differentiated at distinct time points during speech processing: unconfident expressions elicited a weaker P2 than all other expressions of confidence (or neutral-intending utterances), whereas close-to-confident expressions elicited a reduced negative response in the 330e500 msec and 550e740 msec time window. Neutral-intending expressions, which were also perceived as relatively confident, elicited a more delayed, larger sustained positivity than all other expressions in the 980e1270 msec window for this task. These findings provide the first piece of evidence of how quickly the brain responds to vocal cues signifying the extent of a speaker's confidence during online speech comprehension ; first, a rough dissociation between unconfident and confident voices occurs as early as 200 msec after speech onset. At a later stage, further differentiation of the exact level of speaker confidence (i.e., close-to-confident, very confident) is evaluated via an inferential system to determine the speaker's meaning under current task settings. These findings extend three-stage models of how vocal emotion cues are processed in speech comprehension (e.g., Schirmer & Kotz, 2006) by revealing how a speaker's mental state (i.e., feeling of knowing) is simultaneously inferred from vocal expressions.

The basis of the work of electroencephalography (EEG) is the registration of electrical impulses from the brain or some of its individual areas using a special sensor/electrode. This method is used for the treatment and diagnosis of various diseases. The use of wet electrodes in this case does not seem viable, for several well-known reasons. As a result of this, a detailed analysis of modern EEG sensors developed over the past few years is carried out, which will allow researchers to choose this type of sensor more carefully and, as a result, conduct their research more competently. Due to the absence of any standards in the production and testing of dry EEG sensors, the main moment of this manuscript is a detailed description of the necessary steps for testing a dry electrode, which will allow researchers to maximize the potential of the sensor in the various type of research.

This dissertation presents both a theoretical understanding of Maharishi Gandharva Veda music and some exploratory research on its integrating effects for the listener.  Five different experiments investigated the hypothesis that Maharishi Gandharva Veda music would increase psychophysiological balance as indicated by improvements in affect, physiology, and behavior. Experiment 1 measured immediate pre-post effects of five live concerts (N= 697), using a self-report Likert rating scale describing balanced and imbalanced affect. Results indicated (1) the concerts significantly balanced affect, (2) females and males exhibited significantly different patterns of balance, and (3) greater pre-post effects occurred with evening performances.  Experiment 2 examined possible confounds of Experiment 1. Results showed no social compliance effects and that unfamiliarity with Maharishi Gandharva Veda music did not counteract its balancing effects.
Experiments 3-4 looked at effects on EEG, heart rate, and pulse in two case studies. In the first case, Maharishi Gandharva Veda music improved psychophysiological balance as indicated by increased global EEG alpha and theta activity and by changes in the subject’s Maharishi Ayur-Vedic pulse. This EEG pattern is similar to that produced in Maharishi’s Transcendental Meditation technique. In the second case frontal beta increased, possibly being associated with bliss during the subject’s deepest experience.
Experiment 5 measured immediate effects of Maharishi Gandharva Veda music on a psychiatric, institutionalized geriatric population. 27 subjects, randomly assigned to two groups, listened to 20 min selections of either Maharishi Gandharva Veda music or Western Baroque music five days a week for eight weeks. Previous investigators have shown that the Western Baroque selections had significant therapeutic effects. Dependent variables were the Brief Psychiatric Rating Scale, Fairview Self-Help Scale, and structured observations. No significant differences were found between groups for the rating scales, indicating Maharishi Gandharva Veda music was at least as therapeutic in value as Western Baroque. Structured observations indicated the Maharishi Gandharva Veda group demonstrated greater improvement in social behavior.
Together, the five experiments suggest Maharishi Gandharva Veda music can be a powerful tool for balancing the individual’s mind, body, and behavior. Further research is needed to confirm these initial findings.

Manual processing of sleep recordings is extremely time-consuming. Efforts to automate this process have shown promising results, but automatic systems are generally evaluated on private databases, not allowing accurate cross-validation with other systems. In lacking a common benchmark, the relative performances of different systems are not compared easily and advances are compromised. To address this fundamental methodological impediment to sleep study, we propose an open-access database of polysomnographic biosignals. To build this database, whole-night recordings from 200 participants [97 males (aged 42.9+/-19.8 years) and 103 females (aged 38.3+/-18.9 years); age range: 18–76 years] were pooled from eight different research protocols performed in three different hospital-based sleep laboratories. All recordings feature a sampling frequency of 256 Hz and an electroencephalography (EEG) montage of 4–20 channels plus standard electro-oculography (EOG), electromyography (EMG), electrocardiography (ECG) and respiratory signals. Access to the database can be obtained through the Montreal Archive of Sleep Studies (MASS) website (http://www.ceams-carsm.ca/en/MASS), and requires only affiliation with a research institution and prior approval by the applicant’s local ethical review board. Providing the research community with access to this free and open sleep database is expected to facilitate the development and cross-validation of sleep analysis automation systems. It is also expected that such a shared resource will be a catalyst for cross-centre collaborations on difficult topics such as improving inter-rater  agreement on sleep stage scoring.

Brain Computer Interfaces (BCIs) are the systems that translate the electrical activity of the brain into the commands to control the devices. A typical BCI system will contain hardware and software. Hardware collects the data from the brain while software processes it and provides feedback to the hardware. In this paper, we discuss about the two key aspects in the BCI research, one, BCI software platforms / toolboxes and second, BCI datasets which are publicly available. We provide short review regarding BCI software with respect to their most important features such as license, programming language involved, requirements of operating software or other commercial software etc.  The BCI software reviewed are BCI2000, OpenVIBE, BCILAB, BCI++, Gtec’s g.BCISys, xBCI and Wyrm. Dataset is one other aspect of the BCI research. We provide short description and comparison of BCI datasets which are available publicly

Educators have long sought to develop critical thinking ability and open-mindedness in their students, as well as to measure this development. Physiological and psychological research studies on practitioners of the Transcendental Meditation (TM) program have showed EEG brain wave coherence to be a measure of the development of orderliness in thinking and expanded awareness. It was hypothesized that EEG phase coherence would provide a neurophysiological correlate of critical thinking ability and open-mindedness. It was also hypothesized that the educational curriculum at Maharishi International University, which as the TM program as its basis, would show seniors to be more developed in critical thinking and open-mindedness than seniors at other universities. Other hypotheses were that critical thinking (as measured by the Watson-Glaser Critical Thinking Appraisal) would correlate positively with open-mindedness (measured using the Rokeach Adult Dogmatism Scale), class, and show no d...

Self-referential processing has been principally investigated using functional magnetic resonance imaging (fMRI). However, understanding of the brain functioning is not possible without careful comparison of the evidence coming from different methodological domains. This paper aims to review electroencephalographic (EEG) studies of self-referential processing and to evaluate how they correspond, complement, or contradict the existing fMRI evidence. There are potentially two approaches to the study of EEG correlates of self-referential processing. Firstly, because simultaneous registration of EEG and fMRI has become possible, the degree of overlap between these two signals in brain regions related to self-referential processing could be determined. Second and more direct approach would be the study of EEG correlates of self-referential processing per se. In this review, I discuss studies, which employed both these approaches and show that in line with fMRI evidence, EEG correlates of...

We focus on the problem of detection of the user’s area of interest within a single web page, or the web page of interest within different web pages. Current methods either use some kind of manual ranking, or apply parameters such as the time the user spends on a specific area of the page to determine the area of interest. We postulate that the attention level of the user while browsing is a more reliable indication of the user’s level of interest. We use EEG inputs from a NeuroSky MindWave headset to capture the user’s attention level in real time. A background script in a web browser in a mobile device captures the part of the webpage currently being browsed by noting the percentage of the page that the user has scrolled to. The attention level and the percentage of the page scrolled are mapped using the timestamp as the key. Our solution is integrated with the mobile web browser architecture. Using our method, we determine and map the average attention level within the same page,...

Background: The present study aimed to evaluate the operators' mental workload (MW) of cement, city traffic control and power plant control centers using subjective and objective measures during system vital parameters monitoring. Methods: This cross-sectional study was conducted from June 2014 to February 2015 at the cement, city traffic control and power plant control centers. Electrocardiography and electroencephalography data were recorded from forty males during performing their daily working in resting, low mental workload (LMW), high mental workload (HMW) and recovery conditions (each block 5 minutes). The NASA-Task Load Index (TLX) was used to evaluate the subjective workload of the operators. Results: The results showed that increasing MW had a significant effect on the operators subjective responses in two conditions ([1,53] = 216.303, P < 0.001, η2 = 0.803). Also,the Task-MW interaction effect on operators subjective responses was significant (F [3, 53] = 12.628, P < 0.001, η2 = 0.417). Analysis of repeated measures analysis of variance (ANOVA) indicated that increasing mental demands had a significant effect on heart rate, low frequency/high frequency ratio, theta and alpha band activity. Conclusion: The results suggested that when operators' mental demands especially in traffic control and power plant tasks increased, their mental fatigue and stress level increased and their mental health deteriorated. Therefore, it may be necessary to implement an ergonomic program or administrative control to manage mental probably health in these control centers. Furthermore, by evaluating MW, the control center director can organize the human resources for each MW condition to sustain the appropriate performance as well as improve system functions.

Background: Electroencephalography (EEG) is an elec-trophysiological monitoring method to record electrical activity of the brain. It is typically noninvasive, with the electrodes placed along the scalp. Electromyography (EMG) is an electro diagnostic medicine technique for evaluating and recording the electrical activity produced by skeletal muscles. EMG is performed using an instrument called an electromyography to produce a record called an electro-myogram.