Frontal and parietal EEG alpha asymmetry: a large-scale investigation of short-term reliability on distinct EEG systems

AbstractEEG resting-state alpha asymmetry is one of the most widely investigated forms of functional hemispheric asymmetries in both basic and clinical neuroscience. However, studies yield inconsistent results. One crucial prerequisite to obtain reproducible results is the reliability of the index of interest. There is a body of research suggesting a moderate-to-good reliability of EEG resting-state alpha asymmetry, but unfortunately sample sizes in these studies are typically small. This study presents the first large-scale short-term reliability study of frontal and parietal EEG resting-state alpha asymmetry. We used the Dortmund Vital Study data set containing 370 participants. In each participant, EEG resting state was recorded eight times, twice with their eyes opened, twice with their eyes-closed, each on two different EEG systems. We found good reliability of EEG alpha power and alpha asymmetry on both systems for electrode pairs. We also found that alpha power asymmetry reliability is higher in the eyes-closed condition than in the eyes-open condition. The frontomedial electrode pair showed weaker reliability than the frontolateral and parietal electrode pairs. Interestingly, we found no population-level alpha asymmetry in frontal electrodes, one of the most investigated electrode sites in alpha asymmetry research. In conclusion, our results suggest that while EEG alpha asymmetry is an overall reliable measure, frontal alpha asymmetry should be assessed using multiple electrode pairs.

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Frontal and parietal EEG alpha asymmetry: A large-scale investigation of short-term reliability on distinct EEG systems

10.21203/rs.3.rs-323548/v1 ◽

2021 ◽

Author(s):

Dorothea Metzen ◽

Erhan Genc ◽

Stephan Getzmann ◽

Mauro F. Larra ◽

Edmund Wascher ◽

...

Keyword(s):

Resting State ◽

Large Scale ◽

Brain Regions ◽

Alpha Power ◽

Short Term ◽

Good Reliability ◽

Data Set ◽

Alpha Asymmetry ◽

Eyes Closed ◽

Eeg Alpha

Abstract EEG resting state alpha asymmetry is one of the most widely investigated forms of functional hemispheric asymmetries in both basic and clinical neuroscience. However, studies yield very inconsistent results. One crucial prerequisite to obtain reproducible results is the reliability of the index of interest. There is a body of research suggesting a moderate to good reliability of EEG resting state alpha asymmetry, but unfortunately sample sizes in these studies are typically small. This study presents the first large scale short-term reliability study of frontal and parietal EEG resting state alpha asymmetry. We used the Dortmund Vital Study data set containing 541 participants. In each participant, EEG resting state was recorded eight times, twice with their eyes opened, twice with their eyes closed, each on two different EEG systems. We found good reliability of EEG alpha power and alpha asymmetry on both systems. Interestingly, we found no reliable alpha asymmetry in frontomedial brain regions, one of the most investigate brain regions in alpha asymmetry research. Furthermore, we investigated the link between EEG alpha asymmetry and handedness, since previous studies showed that right-handedness is associated with higher rightward alpha asymmetry. Our results only partly replicate this association. In conclusion, our results suggest that while EEG alpha asymmetry is an overall reliable measure, frontal alpha asymmetry should be assessed by using multiple electrode pairs. Furthermore, the question of EEG alpha asymmetry’s association with handedness remains unsettled and needs further investigation.

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Enabling #EEGManyLabs: Quality in Automatically Preprocessed EEG Data and Psychopathological Associations of Frontal Alpha Asymmetry

10.31219/osf.io/g8udv ◽

2022 ◽

Author(s):

Niklas Schürmann

Keyword(s):

Interrater Reliability ◽

Large Scale ◽

Electrode Pair ◽

Alpha Power ◽

Alpha Asymmetry ◽

Eeg Data ◽

Replication Crisis ◽

State Of Research ◽

The Relationship

Neuroscience is facing a replication crisis. Little effort is invested in replication projects and low power in many studies indicates a potentially poor state of research. To assess replicability of EEG research, the #EEGManyLabs project aims to reproduce the most influential original EEG studies. A spin-off to the main project shall investigate the relationship between frontal alpha asymmetries and psychopathological symptoms, the predictive qualities of which have lately been considered controversial. To ensure that preprocessing of EEG data can be conducted automatically (via Automagic), we tested 47 healthy participants in an EEG resting state paradigm and collected psychopathological measures. We analyzed reliability and quality of manual and automated preprocessing and performed multiple regressions to investigate the association of frontal alpha asymmetries and depression, worry, trait anxiety and COVID-19 related worry. We hypothesized comparably good interrater reliability of preprocessing methods and higher data quality in automatically preprocessed data. We expected associations of leftward frontal alpha asymmetries and higher depression and anxiety scores and significant associations of rightward frontal alpha asymmetries and higher worrying and COVID-19- related worrying. Interrater reliability of preprocessing methods was mostly good, automatically preprocessed data achieved higher quality scores than manually preprocessed data. We uncovered an association of relative rightward lateralization of alpha power at one electrode pair and depressive symptoms. No further associations of interest emerged. We conclude that Automagic is an appropriate tool for large-scale preprocessing. Findings regarding associations of frontal alpha asymmetries and psychopathology likely stem from sample limitations and shrinking effect sizes.

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Three times NO: no relationship between frontal alpha asymmetry and depressive disorders in a multiverse analysis of three studies

10.1101/2020.06.30.180760 ◽

2020 ◽

Author(s):

Aleksandra Kołodziej ◽

Mikołaj Magnuski ◽

Anastasia Ruban ◽

Aneta Brzezicka

Keyword(s):

Data Analysis ◽

Analytical Approach ◽

Depressive Disorders ◽

Alpha Power ◽

Alpha Oscillations ◽

Alpha Asymmetry ◽

Eeg Data ◽

Theoretical Assumptions ◽

Frontal Alpha Asymmetry ◽

Eeg Alpha

AbstractFor decades, the frontal alpha asymmetry (FAA) - a disproportion in EEG alpha oscillations power between right and left frontal channels - has been one of the most popular measures of depressive disorders (DD) in electrophysiology studies. Patients with DD often manifest a left-sided FAA: relatively higher alpha power in the left versus right frontal lobe. Recently, however, multiple studies failed to confirm this effect, questioning its reproducibility. Our purpose is to thoroughly test the validity of FAA in depression by conducting a multiverse analysis - running many related analyses and testing the sensitivity of the effect to changes in the analytical approach - on data from three independent studies. Only two of the 81 analyses revealed significant results. We conclude the paper by discussing theoretical assumptions underlying the FAA and suggest a list of guidelines for improving and expanding the EEG data analysis in future FAA studies.

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Distinct Montages of Slow Oscillatory Transcranial Direct Current Stimulation (so-tDCS) Constitute Different Mechanisms during Quiet Wakefulness

Brain Sciences ◽

10.3390/brainsci9110324 ◽

2019 ◽

Vol 9 (11) ◽

pp. 324

Author(s):

Ping Koo-Poeggel ◽

Verena Böttger ◽

Lisa Marshall

Keyword(s):

Slow Wave Sleep ◽

Brain Activity ◽

Electrode Placement ◽

Brain State ◽

Electrode Pair ◽

Alpha Power ◽

Applied Current ◽

Large Power ◽

Quiet Wakefulness ◽

Eyes Closed

Slow oscillatory- (so-) tDCS has been applied in many sleep studies aimed to modulate brain rhythms of slow wave sleep and memory consolidation. Yet, so-tDCS may also modify coupled oscillatory networks. Efficacy of weak electric brain stimulation is however variable and dependent upon the brain state at the time of stimulation (subject and/or task-related) as well as on stimulation parameters (e.g., electrode placement and applied current. Anodal so-tDCS was applied during wakefulness with eyes-closed to examine efficacy when deviating from the dominant brain rhythm. Additionally, montages of different electrodes size and applied current strength were used. During a period of quiet wakefulness bilateral frontolateral stimulation (F3, F4; return electrodes at ipsilateral mastoids) was applied to two groups: ‘Group small’ (n = 16, f:8; small electrodes: 0.50 cm2; maximal current per electrode pair: 0.26 mA) and ‘Group Large’ (n = 16, f:8; 35 cm2; 0.35 mA). Anodal so-tDCS (0.75 Hz) was applied in five blocks of 5 min epochs with 1 min stimulation-free epochs between the blocks. A finger sequence tapping task (FSTT) was used to induce comparable cortical activity across sessions and subject groups. So-tDCS resulted in a suppression of alpha power over the parietal cortex. Interestingly, in Group Small alpha suppression occurred over the standard band (8–12 Hz), whereas for Group Large power of individual alpha frequency was suppressed. Group Small also revealed a decrease in FSTT performance at retest after stimulation. It is essential to include concordant measures of behavioral and brain activity to help understand variability and poor reproducibility in oscillatory-tDCS studies.

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Revisiting the deformation transients before the 2011 Tohoku-Oki Megathrust Earthquake with GPS

10.5194/egusphere-egu2020-21477 ◽

2020 ◽

Author(s):

Anne Socquet ◽

Lou Marill ◽

David Marsan ◽

Baptiste Rousset ◽

Mathilde Radiguet ◽

...

Keyword(s):

Time Series ◽

Large Scale ◽

Gravity Anomalies ◽

Seismogenic Zone ◽

Double Difference ◽

Ocean Bottom ◽

Slow Slip ◽

Short Term ◽

Data Set ◽

Systematic Analysis

<p>The precursory activity leading up to the Tohoku-Oki earthquake of 2011 has been suggested to feature both long- and short-term episodes of decoupling and suggests a particularly complex slow slip history. The analysis of the F3 solution of the Japanese GPS network suggested that an accelerated slip occurred in the deeper part of the seismogenic zone during the 10 years preceding the earthquake (Heki & Mitsui, EPSL 2013; Mavrommatis et al., GRL 2014; Yokota & Koketsu, Nat. Com. 2015). During the two months preceding the earthquake, no anomaly in the GPS position time series has been revealed so far, although several anomalous geophysical signals have been reported&#160;(an extended foreshock crisis near the future hypocenter (Kato et al., Science 2012), a synchronized increase of intermediate-depth background seismicity (Bouchon et al., Nat Geosc. 2016), a signal in ocean-bottom pressure gauges and on-land strainmeter time series (Ito et al., Tectonoph. 2013), and large scale gravity anomalies that suggest deep-seated slab deformation processes (Panet et al., Nat. Geosc. 2018&#160;; Wang & Burgmann, GRL 2019)).</p><p>We present novel results based on an independent analysis of the Japanese GPS data set. We perform a full reprocessing of the raw data with a double-difference approach, a systematic analysis of the obtained time-series, including noise characterization and network filtering, and make a robust assessment of long- and short-term tectonic aseismic transients preceding the Tohoku-Oki earthquake. An accelerated slip on the lower part of the seismogenic zone over the last decade is confirmed, not only below the epicenter of Tohoku-Oki earthquake but also further south, offshore Boso peninsula, which is a worrying sign of an on-going slow decoupling east of Tokyo. At shorter time-scale, first results seem compatible with a slow slip close to the epicenter initiating ~&#160;2 months before the mainshock.</p>

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Relation Between Frontal Alpha Asymmetry and Anxiety in Young Patients with Generalized Anxiety Disorder

PRILOZI ◽

10.1515/prilozi-2015-0064 ◽

2015 ◽

Vol 36 (2) ◽

pp. 157-177 ◽

Cited By ~ 2

Author(s):

Aneta Demerdzieva ◽

Nada Pop-Jordanova

Keyword(s):

Anxiety Disorder ◽

Generalized Anxiety Disorder ◽

Frontal Region ◽

Generalized Anxiety ◽

Alpha Power ◽

Alpha Asymmetry ◽

Eyes Closed ◽

Frontal Alpha Asymmetry ◽

Eyes Open ◽

The Right

Abstract Frontal alpha asymmetry (the relative difference in power between two signals in different hemispheres) has been suggested as biomarker for anxiety. The goal of this study was to evaluate alpha asymmetry in the frontal region for young people (7-18 years) with generalized anxiety disorder, diagnosed according to two statistic manuals (DMS-IV-R and ICD-10), the medical history and the neuropsychological assessment. The QEEG recording and analysis of the obtained results from alpha spectra power and log of alpha spectra power are made in four conditions (eyes open, eyes closed, VCPT and ACPT). The obtained results for alpha power in general showed higher cortical activity in the right hemisphere, associated with negative emotions. The calculated alpha asymmetry separate for eyes open, eyes closed, VCPT and ACPT conditions showed the right activation in all four conditions. In addition, the right frontal asymmetry was specific for the Fp1-Fp2 region, while a greater left frontal activation was recorded for the F7-F8 region. The log of alpha power in general was additionally analyzed. The calculated asymmetry score in general (in a way that the left log transformed score was subtracted from the right) confirmed a greater right activation. Testing the power of the whole alpha band (μV2) in general, for all four conditions and for frontal region confirmed the right alpha asymmetries in all participants. The right alpha asymmetry in the frontal region was specific only for the Fp1-Fp2 region (frontopolar region). The only greater left frontal activation was registered between the F7-F8 region. Our findings are supported by many other studies using specific localization methods like fMRI or LORETA source localization.

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Street Demonstrations and the Media Agenda: An Analysis of the Dynamics of Protest Agenda Setting

Comparative Political Studies ◽

10.1177/0010414019830736 ◽

2019 ◽

Vol 52 (13-14) ◽

pp. 2283-2313 ◽

Cited By ~ 3

Author(s):

Will Jennings ◽

Clare Saunders

Keyword(s):

Agenda Setting ◽

Media Coverage ◽

Large Scale ◽

Dynamic Theory ◽

Short Term ◽

Cross Sectional ◽

Data Set ◽

Media Agenda ◽

The Media ◽

Sectional Analysis

This article argues that the agenda-setting power of protest must be understood in dynamic terms. Specifically, it develops and tests a dynamic theory of media reaction to protest which posits that features of street demonstrations—such as their size, violence, societal conflict, and the presence of a “trigger”—lead protest issues to be reported and sustained in the media agenda over time. We conduct a unique empirical analysis of media coverage of protest issues, based upon a data set of 48 large-scale street demonstrations in nine countries. Time-series cross-sectional analysis is used to estimate the dynamic effects of demonstration features on media coverage of the protest issue. The findings show that violence can increase media attention in the short term and larger protest size sustains it over the longer term. The agenda-setting power of protest is structured in time.

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Directionality of large-scale resting-state brain networks during eyes open and eyes closed conditions

Frontiers in Human Neuroscience ◽

10.3389/fnhum.2015.00081 ◽

2015 ◽

Vol 9 ◽

Cited By ~ 12

Author(s):

Delong Zhang ◽

Bishan Liang ◽

Xia Wu ◽

Zengjian Wang ◽

Pengfei Xu ◽

...

Keyword(s):

Resting State ◽

Large Scale ◽

Brain Networks ◽

Eyes Closed ◽

Eyes Open

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Resting-state brain network features associated with short-term skill learning ability in humans and the influence of N-methyl-d-aspartate receptor antagonism

Network Neuroscience ◽

10.1162/netn_a_00045 ◽

2018 ◽

Vol 2 (4) ◽

pp. 464-480 ◽

Cited By ~ 5

Author(s):

Zhenxiang Zang ◽

Lena S. Geiger ◽

Urs Braun ◽

Hengyi Cao ◽

Maria Zangl ◽

...

Keyword(s):

Motor Learning ◽

Skill Acquisition ◽

Resting State ◽

Intraclass Correlation ◽

Brain Network ◽

Skill Learning ◽

Learning Ability ◽

Short Term ◽

Characteristic Path Length ◽

Good Reliability

Graph theoretical functional magnetic resonance imaging (fMRI) studies have demonstrated that brain networks reorganize significantly during motor skill acquisition, yet the associations between motor learning ability, brain network features, and the underlying biological mechanisms remain unclear. In the current study, we applied a visually guided sequential pinch force learning task and graph theoretical analyses to investigate the associations between short-term motor learning ability and resting-state brain network metrics in 60 healthy subjects. We further probed the test-retest reliability ( n = 26) and potential effects of the N-methyl-d-aspartate (NMDA) antagonist ketamine ( n = 19) in independent healthy volunteers. Our results show that the improvement of motor performance after short-term training was positively correlated with small-worldness ( p = 0.032) and global efficiency ( p = 0.025), whereas negatively correlated with characteristic path length ( p = 0.014) and transitivity ( p = 0.025). In addition, using network-based statistics (NBS), we identified a learning ability–associated ( p = 0.037) and ketamine-susceptible ( p = 0.027) cerebellar-cortical network with fair to good reliability (intraclass correlation coefficient [ICC] > 0.7) and higher functional connectivity in better learners. Our results provide new evidence for the association of intrinsic brain network features with motor learning and suggest a role of NMDA-related glutamatergic processes in learning-associated subnetworks.

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Resting-State Functional Connectivity of the Ageing Female Brain—Differences Between Young and Elderly Female Adults on Multislice Short TR rs-fMRI

Frontiers in Neurology ◽

10.3389/fneur.2021.645974 ◽

2021 ◽

Vol 12 ◽

Author(s):

Przemysław Podgórski ◽

Marta Waliszewska-Prosół ◽

Anna Zimny ◽

Marek Sąsiadek ◽

Joanna Bladowska

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Large Scale ◽

World Health ◽

Resting State Functional Connectivity ◽

Default Mode ◽

Young Females ◽

Eyes Closed ◽

Age Related ◽

Healthy Female

Introduction: Age-related brain changes are one of the most important world health problems due to the rising lifespan and size of the elderly populations. The aim of the study was to assess the effect of ageing in women on coordinated brain activity between eight resting-state networks.Material and Methods: The study group comprised 60 healthy female volunteers who were divided into two age groups: younger women (aged 20–30 n = 30) and older women (aged 55–80 n = 30). Resting-state data were collected during a 15 min scan in the eyes-closed condition using a 3T MR scanner. Data were preprocessed and analysed using the CONN toolbox version 19.c. The large-scale network analysis included a priori selected regions of interest of the default mode, the sensorimotor, the visual, the salience, the dorsal attention, the fronto-parietal, the language, and the cerebellar network.Results: Within the visual, the default mode, the salience, and the sensorimotor network, the intra-network resting-state functional connectivity (RSFC) was significantly higher with increasing age. There was also a significant increase in the inter-network RSFC in older females compared to young females found in the following networks: sensorimotor lateral and salience, salience and language, salience and fronto-parietal, cerebellar anterior and default mode, cerebellar posterior and default mode, visual and sensorimotor lateral, visual and sensorimotor, visual lateral and default mode, language and cerebellar anterior, language and cerebellar posterior, fronto-parietal and cerebellar anterior, dorsal attention and sensorimotor, dorsal attention and default mode, sensorimotor superior, and salience. Compared to young females, elderly women presented bilaterally significantly lower inter-network RSFC of the salience supramarginal gyrus and cerebellar posterior, sensorimotor lateral, and cerebellar anterior network, and sensorimotor lateral and cerebellar posterior as well as sensorimotor superior and cerebellar posterior network.Conclusion: Increased RSFC between some brain networks including the visual, the default mode, the salience, the sensorimotor, the language, the fronto-parietal, the dorsal attention, and the cerebellar networks in elderly females may function as a compensation mechanism during the ageing process of the brain. To the best of our knowledge, this study is the first to report the importance of increase of cerebellar networks RSFC during healthy female ageing.

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