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1.
PLoS One ; 19(6): e0305082, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38870189

RESUMO

Alpha waves, one of the major components of resting and awake cortical activity in human electroencephalography (EEG), are known to show waxing and waning, but this phenomenon has rarely been analyzed. In the present study, we analyzed this phenomenon from the viewpoint of excitation and inhibition. The alpha wave envelope was subjected to secondary differentiation. This gave the positive (acceleration positive, Ap) and negative (acceleration negative, An) values of acceleration and their ratio (Ap-An ratio) at each sampling point of the envelope signals for 60 seconds. This analysis was performed on 36 participants with Alzheimer's disease (AD), 23 with frontotemporal dementia (FTD) and 29 age-matched healthy participants (NC) whose data were provided as open datasets. The mean values of the Ap-An ratio for 60 seconds at each EEG electrode were compared between the NC and AD/FTD groups. The AD (1.41 ±0.01 (SD)) and FTD (1.40 ±0.02) groups showed a larger Ap-An ratio than the NC group (1.38 ±0.02, p<0.05). A significant correlation between the envelope amplitude of alpha activity and the Ap-An ratio was observed at most electrodes in the NC group (Pearson's correlation coefficient, r = -0.92 ±0.15, mean for all electrodes), whereas the correlation was disrupted in AD (-0.09 ±0.21, p<0.05) and disrupted in the frontal region in the FTD group. The present method analyzed the envelope of alpha waves from a new perspective, that of excitation and inhibition, and it could detect properties of the EEG, Ap-An ratio, that have not been revealed by existing methods. The present study proposed a new method to analyze the alpha activity envelope in electroencephalography, which could be related to excitatory and inhibitory neural activity.


Assuntos
Ritmo alfa , Doença de Alzheimer , Eletroencefalografia , Demência Frontotemporal , Humanos , Masculino , Feminino , Eletroencefalografia/métodos , Idoso , Doença de Alzheimer/fisiopatologia , Ritmo alfa/fisiologia , Demência Frontotemporal/fisiopatologia , Pessoa de Meia-Idade , Estudos de Casos e Controles
2.
Sci Rep ; 14(1): 12796, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834699

RESUMO

Imagining natural scenes enables us to engage with a myriad of simulated environments. How do our brains generate such complex mental images? Recent research suggests that cortical alpha activity carries information about individual objects during visual imagery. However, it remains unclear if more complex imagined contents such as natural scenes are similarly represented in alpha activity. Here, we answer this question by decoding the contents of imagined scenes from rhythmic cortical activity patterns. In an EEG experiment, participants imagined natural scenes based on detailed written descriptions, which conveyed four complementary scene properties: openness, naturalness, clutter level and brightness. By conducting classification analyses on EEG power patterns across neural frequencies, we were able to decode both individual imagined scenes as well as their properties from the alpha band, showing that also the contents of complex visual images are represented in alpha rhythms. A cross-classification analysis between alpha power patterns during the imagery task and during a perception task, in which participants were presented images of the described scenes, showed that scene representations in the alpha band are partly shared between imagery and late stages of perception. This suggests that alpha activity mediates the top-down re-activation of scene-related visual contents during imagery.


Assuntos
Ritmo alfa , Eletroencefalografia , Imaginação , Percepção Visual , Humanos , Imaginação/fisiologia , Masculino , Feminino , Ritmo alfa/fisiologia , Adulto , Percepção Visual/fisiologia , Adulto Jovem , Estimulação Luminosa , Córtex Cerebral/fisiologia
3.
Sci Rep ; 14(1): 13039, 2024 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844793

RESUMO

Sleep onset insomnia is a pervasive problem that contributes significantly to the poor health outcomes associated with insufficient sleep. Auditory stimuli phase-locked to slow-wave sleep oscillations have been shown to augment deep sleep, but it is unknown whether a similar approach can be used to accelerate sleep onset. The present randomized controlled crossover trial enrolled adults with objectively verified sleep onset latencies (SOLs) greater than 30 min to test the effect of auditory stimuli delivered at specific phases of participants' alpha oscillations prior to sleep onset. During the intervention week, participants wore an electroencephalogram (EEG)-enabled headband that delivered acoustic pulses timed to arrive anti-phase with alpha for 30 min (Stimulation). During the Sham week, the headband silently recorded EEG. The primary outcome was SOL determined by blinded scoring of EEG records. For the 21 subjects included in the analyses, stimulation had a significant effect on SOL according to a linear mixed effects model (p = 0.0019), and weekly average SOL decreased by 10.5 ± 15.9 min (29.3 ± 44.4%). These data suggest that phase-locked acoustic stimulation can be a viable alternative to pharmaceuticals to accelerate sleep onset in individuals with prolonged sleep onset latencies. Trial Registration: This trial was first registered on clinicaltrials.gov on 24/02/2023 under the name Sounds Locked to ElectroEncephalogram Phase For the Acceleration of Sleep Onset Time (SLEEPFAST), and assigned registry number NCT05743114.


Assuntos
Estimulação Acústica , Eletroencefalografia , Distúrbios do Início e da Manutenção do Sono , Humanos , Masculino , Feminino , Adulto , Distúrbios do Início e da Manutenção do Sono/terapia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Estimulação Acústica/métodos , Pessoa de Meia-Idade , Estudos Cross-Over , Resultado do Tratamento , Ritmo alfa/fisiologia
4.
J Neural Eng ; 21(3)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38834060

RESUMO

Objective.The corticospinal responses of the motor network to transcranial magnetic stimulation (TMS) are highly variable. While often regarded as noise, this variability provides a way of probing dynamic brain states related to excitability. We aimed to uncover spontaneously occurring cortical states that alter corticospinal excitability.Approach.Electroencephalography (EEG) recorded during TMS registers fast neural dynamics-unfortunately, at the cost of anatomical precision. We employed analytic Common Spatial Patterns technique to derive excitability-related cortical activity from pre-TMS EEG signals while overcoming spatial specificity issues.Main results.High corticospinal excitability was predicted by alpha-band activity, localized adjacent to the stimulated left motor cortex, and suggesting a travelling wave-like phenomenon towards frontal regions. Low excitability was predicted by alpha-band activity localized in the medial parietal-occipital and frontal cortical regions.Significance.We established a data-driven approach for uncovering network-level neural activity that modulates TMS effects. It requires no prior anatomical assumptions, while being physiologically interpretable, and can be employed in both exploratory investigation and brain state-dependent stimulation.


Assuntos
Eletroencefalografia , Potencial Evocado Motor , Córtex Motor , Rede Nervosa , Tratos Piramidais , Estimulação Magnética Transcraniana , Humanos , Estimulação Magnética Transcraniana/métodos , Masculino , Tratos Piramidais/fisiologia , Adulto , Feminino , Córtex Motor/fisiologia , Eletroencefalografia/métodos , Rede Nervosa/fisiologia , Potencial Evocado Motor/fisiologia , Adulto Jovem , Ritmo alfa/fisiologia
5.
Cereb Cortex ; 34(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38850214

RESUMO

States of consciousness are likely mediated by multiple parallel yet interacting cortico-subcortical recurrent networks. Although the mesocircuit model has implicated the pallidocortical circuit as one such network, this circuit has not been extensively evaluated to identify network-level electrophysiological changes related to loss of consciousness (LOC). We characterize changes in the mesocircuit in awake versus propofol-induced LOC in humans by directly simultaneously recording from sensorimotor cortices (S1/M1) and globus pallidus interna and externa (GPi/GPe) in 12 patients with Parkinson disease undergoing deep brain stimulator implantation. Propofol-induced LOC is associated with increases in local power up to 20 Hz in GPi, 35 Hz in GPe, and 100 Hz in S1/M1. LOC is likewise marked by increased pallidocortical alpha synchrony across all nodes, with increased alpha/low beta Granger causal (GC) flow from GPe to all other nodes. In contrast, LOC is associated with decreased network-wide beta coupling and beta GC from M1 to the rest of the network. Results implicate an important and possibly central role of GPe in mediating LOC-related increases in alpha power, supporting a significant role of the GPe in modulating cortico-subcortical circuits for consciousness. Simultaneous LOC-related suppression of beta synchrony highlights that distinct oscillatory frequencies act independently, conveying unique network activity.


Assuntos
Ritmo alfa , Globo Pálido , Propofol , Inconsciência , Humanos , Propofol/farmacologia , Globo Pálido/efeitos dos fármacos , Globo Pálido/fisiologia , Masculino , Feminino , Pessoa de Meia-Idade , Inconsciência/induzido quimicamente , Inconsciência/fisiopatologia , Ritmo alfa/efeitos dos fármacos , Ritmo alfa/fisiologia , Idoso , Doença de Parkinson/fisiopatologia , Estimulação Encefálica Profunda/métodos , Anestésicos Intravenosos/farmacologia , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/fisiologia , Eletroencefalografia
6.
Sci Rep ; 14(1): 12007, 2024 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796618

RESUMO

Recent studies suggest that noninvasive imaging methods (EEG, MEG) in the human brain scalp can decode the content of visual features information (orientation, color, motion, etc.) in Visual-Working Memory (VWM). Previous work demonstrated that with the sustained low-frequency Event-Related Potential (ERP under 6 Hz) of scalp EEG distributions, it is possible to accurately decode the content of orientation information in VWM during the delay interval. In addition, previous studies showed that the raw data captured by a combination of the occi-parietal electrodes could be used to decode the orientation. However, it is unclear whether the orientation information is available in other frequency bands (higher than 6 Hz) or whether this information is feasible with fewer electrodes. Furthermore, the exploration of orientation information in the phase values of the signal has not been well-addressed. In this study, we propose that orientation information is also accessible through the phase consistency of the occipital region in the alpha band frequency. Our results reveal a significant difference between orientations within 200 ms after stimulus offset in early visual sensory processing, with no apparent effect in power and Event-Related Oscillation (ERO) during this period. Additionally, in later periods (420-500 ms after stimulus offset), a noticeable difference is observed in the phase consistency of low gamma-band activity in the occipital area. Importantly, our findings suggest that phase consistency between trials of the orientation feature in the occipital alpha and low gamma-band can serve as a measure to obtain orientation information in VWM. Furthermore, the study demonstrates that phase consistency in the alpha and low gamma band can reflect the distribution of orientation-selective neuron numbers in the four main orientations in the occipital area.


Assuntos
Eletroencefalografia , Humanos , Masculino , Eletroencefalografia/métodos , Feminino , Adulto , Adulto Jovem , Ritmo alfa/fisiologia , Percepção Visual/fisiologia , Estimulação Luminosa , Memória de Curto Prazo/fisiologia , Orientação/fisiologia , Ritmo Gama/fisiologia , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Potenciais Evocados/fisiologia
7.
Neuroimage ; 294: 120637, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38714216

RESUMO

In recent years, brainprint recognition has emerged as a novel method of personal identity verification. Although studies have demonstrated the feasibility of this technology, some limitations hinder its further development into the society, such as insufficient efficiency (extended wear time for multi-channel EEG cap), complex experimental paradigms (more time in learning and completing experiments), and unclear neurobiological characteristics (lack of intuitive biomarkers and an inability to eliminate the impact of noise on individual differences). Overall, these limitations are due to the incomplete understanding of the underlying neural mechanisms. Therefore, this study aims to investigate the neural mechanisms behind brainwave recognition and simplify the operation process. We recorded prefrontal resting-state EEG data from 40 participants, which is followed up over nine months using a single-channel portable brainwave device. We found that portable devices can effectively and stably capture the characteristics of different subjects in the alpha band (8-13Hz) over long periods, as well as capturing their individual differences (no alpha peak, 1 alpha peak, or 2 alpha peaks). Through correlation analysis, alpha-band activity can reveal the uniqueness of the subjects compared to others within one minute. We further used a descriptive model to dissect the oscillatory and non-oscillatory components in the alpha band, demonstrating the different contributions of fine oscillatory features to individual differences (especially amplitude and bandwidth). Our study validated the feasibility of portable brainwave devices in brainwave recognition and the underlying neural oscillation mechanisms. The fine characteristics of various alpha oscillations will contribute to the accuracy of brainwave recognition, providing new insights for the development of future brainwave recognition technology.


Assuntos
Eletroencefalografia , Humanos , Masculino , Feminino , Adulto , Eletroencefalografia/instrumentação , Eletroencefalografia/métodos , Adulto Jovem , Ritmo alfa/fisiologia , Encéfalo/fisiologia , Córtex Pré-Frontal/fisiologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-38801679

RESUMO

Compared to traditional continuous performance tasks, virtual reality-based continuous performance tests (VR-CPT) offer higher ecological validity. While previous studies have primarily focused on behavioral outcomes in VR-CPT and incorporated various distractors to enhance ecological realism, little attention has been paid to the effects of distractors on EEG. Therefore, our study aimed to investigate the influence of distractors on EEG during VR-CPT. We studied visual distractors and auditory distractors separately, recruiting 68 subjects (M =20.82, SD =1.72) and asking each to complete four tasks. These tasks were categorized into four groups according to the presence or absence of visual and auditory distractors. We conducted paired t-tests on the mean relative power of the five electrodes in the ROI region across different frequency bands. Significant differences were found in theta waves between Group 3 (M =2.49, SD =2.02) and Group 4 (M =2.68, SD =2.39) (p < 0.05); in alpha waves between Group 3 (M =2.08, SD =3.73) and Group 4 (M =3.03, SD =4.60) (p < 0.001); and in beta waves between Group 1 (M = -4.44 , SD =2.29) and Group 2 (M = -5.03 , SD =2.48) (p < 0.001), as well as between Group 3 (M = -4.48 , SD =2.03) and Group 4 (M = -4.67 , SD =2.23) (p < 0.05). The incorporation of distractors in VR-CPT modulates EEG signals across different frequency bands, with visual distractors attenuating theta band activity, auditory distractors enhancing alpha band activity, and both types of distractors reducing beta oscillations following target stimuli. This insight holds significant promise for the rehabilitation of children and adolescents with attention deficits.


Assuntos
Atenção , Eletroencefalografia , Realidade Virtual , Humanos , Masculino , Feminino , Eletroencefalografia/métodos , Adulto Jovem , Atenção/fisiologia , Adulto , Percepção Visual/fisiologia , Ritmo Teta/fisiologia , Estimulação Acústica/métodos , Ritmo alfa/fisiologia , Estimulação Luminosa , Percepção Auditiva/fisiologia , Desempenho Psicomotor/fisiologia
9.
Hear Res ; 449: 109032, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38797035

RESUMO

Neurons within a neuronal network can be grouped by bottom-up and top-down influences using synchrony in neuronal oscillations. This creates the representation of perceptual objects from sensory features. Oscillatory activity can be differentiated into stimulus-phase-locked (evoked) and non-phase-locked (induced). The former is mainly determined by sensory input, the latter by higher-level (cortical) processing. Effects of auditory deprivation on cortical oscillations have been studied in congenitally deaf cats (CDCs) using cochlear implant (CI) stimulation. CI-induced alpha, beta, and gamma activity were compromised in the auditory cortex of CDCs. Furthermore, top-down information flow between secondary and primary auditory areas in hearing cats, conveyed by induced alpha oscillations, was lost in CDCs. Here we used the matching pursuit algorithm to assess components of such oscillatory activity in local field potentials recorded in primary field A1. Additionally to the loss of induced alpha oscillations, we also found a loss of evoked theta activity in CDCs. The loss of theta and alpha activity in CDCs can be directly related to reduced high-frequency (gamma-band) activity due to cross-frequency coupling. Here we quantified such cross-frequency coupling in adult 1) hearing-experienced, acoustically stimulated cats (aHCs), 2) hearing-experienced cats following acute pharmacological deafening and subsequent CIs, thus in electrically stimulated cats (eHCs), and 3) electrically stimulated CDCs. We found significant cross-frequency coupling in all animal groups in > 70% of auditory-responsive sites. The predominant coupling in aHCs and eHCs was between theta/alpha phase and gamma power. In CDCs such coupling was lost and replaced by alpha oscillations coupling to delta/theta phase. Thus, alpha/theta oscillations synchronize high-frequency gamma activity only in hearing-experienced cats. The absence of induced alpha and theta oscillations contributes to the loss of induced gamma power in CDCs, thereby signifying impaired local network activity.


Assuntos
Estimulação Acústica , Córtex Auditivo , Surdez , Ritmo Gama , Animais , Gatos , Córtex Auditivo/fisiopatologia , Surdez/fisiopatologia , Surdez/congênito , Implantes Cocleares , Ritmo alfa , Potenciais Evocados Auditivos , Algoritmos , Vias Auditivas/fisiopatologia , Modelos Animais de Doenças , Ritmo Teta
10.
J Affect Disord ; 359: 269-276, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38795776

RESUMO

Changes in EEG have been reported in both major depressive disorder (MDD) and bipolar disorder (BD). Specifically, power changes in EEG alpha and theta frequency bands during rest and task are known in both disorders. This leaves open whether there are changes in yet another component of the electrophysiological EEG signal, namely phase-related processes that may allow for distinguishing MDD and BD. For that purpose, we investigate EEG-based spontaneous phase in the resting state of MDD, BD and healthy controls. Our main findings show: (i) decreased spontaneous phase variability in frontal theta of both MDD and BD compared to HC; (ii) decreased spontaneous phase variability in central-parietal alpha in MDD compared to both BD and HC; (iii) increased delays or lags of alpha phase cycles in MDD (but not in BD), which (iv) correlate with the decreased phase variability in MDD. Together, we show similar (decreased frontal theta variability) and distinct (decreased central-parietal alpha variability with increased lags or delays) findings in the spontaneous phase dynamics of MDD and BD. This suggests potential relevance of theta and alpha phase dynamics in distinguishing MDD and BD in clinical differential-diagnosis.


Assuntos
Ritmo alfa , Transtorno Bipolar , Transtorno Depressivo Maior , Eletroencefalografia , Lobo Frontal , Ritmo Teta , Humanos , Transtorno Bipolar/fisiopatologia , Transtorno Bipolar/diagnóstico , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/diagnóstico , Adulto , Masculino , Feminino , Ritmo Teta/fisiologia , Ritmo alfa/fisiologia , Lobo Frontal/fisiopatologia , Diagnóstico Diferencial , Pessoa de Meia-Idade , Lobo Parietal/fisiopatologia , Adulto Jovem , Descanso/fisiologia , Córtex Cerebral/fisiopatologia
11.
Behav Brain Res ; 469: 115063, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38777262

RESUMO

Goal-directed acting requires the integration of sensory information but can also be performed without direct sensory input. Examples of this can be found in sports and can be conceptualized by feedforward processes. There is, however, still a lack of understanding of the temporal neural dynamics and neuroanatomical structures involved in such processes. In the current study, we used EEG beamforming methods and examined 37 healthy participants in two well-controlled experiments varying the necessity of anticipatory processes during goal-directed action. We found that alpha and beta activity in the medial and posterior cingulate cortex enabled feedforward predictions about the position of an object based on the latest sensorimotor state. On this basis, theta band activity seems more related to sensorimotor representations, while beta band activity would be more involved in setting up the structure of the neural representations themselves. Alpha band activity in sensory cortices reflects an intensified gating of the anticipated perceptual consequences of the to-be-executed action. Together, the findings indicate that goal-directed acting through the anticipation of the predicted state of an effector is based on accompanying processes in multiple frequency bands in midcingulate and sensory brain regions.


Assuntos
Eletroencefalografia , Imaginação , Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Imaginação/fisiologia , Objetivos , Encéfalo/fisiologia , Ritmo alfa/fisiologia , Giro do Cíngulo/fisiologia , Antecipação Psicológica/fisiologia , Ritmo beta/fisiologia , Desempenho Psicomotor/fisiologia , Ondas Encefálicas/fisiologia
12.
Int J Psychophysiol ; 201: 112355, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38718899

RESUMO

Processes typically encompassed by working memory (WM) include encoding, retention, and retrieval of information. Previous research has demonstrated that motivation can influence WM performance, although the specific WM processes affected by motivation are not yet fully understood. In this study, we investigated the effects of motivation on different WM processes, examining how task difficulty modulates these effects. We hypothesized that motivation level and personality traits of the participants (N = 48, 32 females; mean age = 21) would modulate the parietal alpha and frontal theta electroencephalography (EEG) correlates of WM encoding, retention, and retrieval phases of the Sternberg task. This effect was expected to be more pronounced under conditions of very high task difficulty. We found that increasing difficulty led to reduced accuracy and increased response time, but no significant relationship was found between motivation and accuracy. However, EEG data revealed that motivation influenced WM processes, as indicated by changes in alpha and theta oscillations. Specifically, higher levels of the Resilience trait-associated with mental toughness, hardiness, self-efficacy, achievement motivation, and low anxiety-were related to increased alpha desynchronization during encoding and retrieval. Increased scores of Subjective Motivation to perform well in the task were related to enhanced frontal midline theta during retention. Additionally, these effects were significantly stronger under conditions of high difficulty. These findings provide insights into the specific WM processes that are influenced by motivation, and underscore the importance of considering both task difficulty and intrinsic motivation in WM research.


Assuntos
Eletroencefalografia , Memória de Curto Prazo , Motivação , Humanos , Feminino , Memória de Curto Prazo/fisiologia , Motivação/fisiologia , Masculino , Adulto Jovem , Adulto , Ritmo alfa/fisiologia , Ritmo Teta/fisiologia , Personalidade/fisiologia , Adolescente
13.
Exp Brain Res ; 242(6): 1253-1265, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38691137

RESUMO

We examined whether the alpha-band coherence between the T7-Fz (verbal analytical-motor planning) brain areas were related to superior performance in sports. We searched for related papers across eight databases: ProQuest Central, ProQuest Psychology Journals, PsycARTICLES, PsycINFO, SPORTDiscus, MEDLINE, Scopus, and Web of Science using relevant keywords (i.e., EEG AND sports AND coherence). Seven studies, with a total of 194 participants, met our inclusion criteria and were shortlisted for statistical analysis. We compared EEG coherence data for both within-subject and between-subject experimental designs. Our analysis revealed that athletes had lower coherence in the T7-Fz brain pathway for alpha- band activation (Hedges' g = - 0.54; p = 0.03) when performing better. Theoretically, these results corroborate the notion that athletes become more "neurally efficient" as the verbal and motor areas of their brains function more independently, i.e., the neural efficiency hypothesis. Accordingly, athletes who can limit verbal interference are more likely to perform a sporting task successfully.


Assuntos
Ritmo alfa , Desempenho Atlético , Humanos , Ritmo alfa/fisiologia , Desempenho Atlético/fisiologia , Encéfalo/fisiologia , Eletroencefalografia/métodos , Desempenho Psicomotor/fisiologia
14.
PLoS One ; 19(5): e0300128, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758733

RESUMO

Interpersonal touch plays a crucial role in human communication, development, and wellness. Mediated interpersonal touch (MIT), a technology to distance or virtually simulated interpersonal touch, has received significant attention to counteract the negative consequences of touch deprivation. Studies investigating the effectiveness of MIT have primarily focused on self-reporting or behavioral correlates. It is largely unknown how MIT affects neural processes such as interbrain functional connectivity during human interactions. Given how users exchange haptic information simultaneously during interpersonal touch, interbrain functional connectivity provides a more ecologically valid way of studying the neural correlates associated with MIT. In this study, a palm squeeze task is designed to examine interbrain synchrony associated with MIT using EEG-based hyperscanning methodology. The phase locking value (PLV) index is used to measure interbrain synchrony. Results demonstrate that MIT elicits a significant increase in alpha interbrain synchronization between participants' brains. Especially, there was a significant difference in the alpha PLV indices between no MIT and MIT conditions in the early stage (130-470 ms) of the interaction period (t-test, p < 0.05). Given the role that alpha interbrain synchrony plays during social interaction, a significant increase in PLV index during MIT interaction seems to indicate an effect of social coordination. The findings and limitations of this study are further discussed, and perspectives on future research are provided.


Assuntos
Encéfalo , Eletroencefalografia , Relações Interpessoais , Tato , Humanos , Encéfalo/fisiologia , Masculino , Feminino , Adulto Jovem , Tato/fisiologia , Adulto , Ritmo alfa/fisiologia , Percepção do Tato/fisiologia , Interação Social
15.
Brain Behav ; 14(5): e3517, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38702896

RESUMO

INTRODUCTION: Attention and working memory are key cognitive functions that allow us to select and maintain information in our mind for a short time, being essential for our daily life and, in particular, for learning and academic performance. It has been shown that musical training can improve working memory performance, but it is still unclear if and how the neural mechanisms of working memory and particularly attention are implicated in this process. In this work, we aimed to identify the oscillatory signature of bimodal attention and working memory that contributes to improved working memory in musically trained children. MATERIALS AND METHODS: We recruited children with and without musical training and asked them to complete a bimodal (auditory/visual) attention and working memory task, whereas their brain activity was measured using electroencephalography. Behavioral, time-frequency, and source reconstruction analyses were made. RESULTS: Results showed that, overall, musically trained children performed better on the task than children without musical training. When comparing musically trained children with children without musical training, we found modulations in the alpha band pre-stimuli onset and the beginning of stimuli onset in the frontal and parietal regions. These correlated with correct responses to the attended modality. Moreover, during the end phase of stimuli presentation, we found modulations correlating with correct responses independent of attention condition in the theta and alpha bands, in the left frontal and right parietal regions. CONCLUSIONS: These results suggest that musically trained children have improved neuronal mechanisms for both attention allocation and memory encoding. Our results can be important for developing interventions for people with attention and working memory difficulties.


Assuntos
Ritmo alfa , Atenção , Memória de Curto Prazo , Música , Ritmo Teta , Humanos , Memória de Curto Prazo/fisiologia , Atenção/fisiologia , Masculino , Feminino , Criança , Ritmo Teta/fisiologia , Ritmo alfa/fisiologia , Percepção Auditiva/fisiologia , Eletroencefalografia , Percepção Visual/fisiologia , Encéfalo/fisiologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-38717876

RESUMO

Neurovascular coupling (NVC) provides important insights into the intricate activity of brain functioning and may aid in the early diagnosis of brain diseases. Emerging evidences have shown that NVC could be assessed by the coupling between electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS). However, this endeavor presents significant challenges due to the absence of standardized methodologies and reliable techniques for coupling analysis of these two modalities. In this study, we introduced a novel method, i.e., the collaborative multi-output variational Gaussian process convergent cross-mapping (CMVGP-CCM) approach to advance coupling analysis of EEG and fNIRS. To validate the robustness and reliability of the CMVGP-CCM method, we conducted extensive experiments using chaotic time series models with varying noise levels, sequence lengths, and causal driving strengths. In addition, we employed the CMVGP-CCM method to explore the NVC between EEG and fNIRS signals collected from 26 healthy participants using a working memory (WM) task. Results revealed a significant causal effect of EEG signals, particularly the delta, theta, and alpha frequency bands, on the fNIRS signals during WM. This influence was notably observed in the frontal lobe, and its strength exhibited a decline as cognitive demands increased. This study illuminates the complex connections between brain electrical activity and cerebral blood flow, offering new insights into the underlying NVC mechanisms of WM.


Assuntos
Algoritmos , Eletroencefalografia , Memória de Curto Prazo , Acoplamento Neurovascular , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Eletroencefalografia/métodos , Masculino , Feminino , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adulto , Distribuição Normal , Acoplamento Neurovascular/fisiologia , Adulto Jovem , Memória de Curto Prazo/fisiologia , Voluntários Saudáveis , Reprodutibilidade dos Testes , Análise Multivariada , Lobo Frontal/fisiologia , Lobo Frontal/diagnóstico por imagem , Mapeamento Encefálico/métodos , Ritmo Teta/fisiologia , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Dinâmica não Linear , Ritmo Delta/fisiologia , Ritmo alfa/fisiologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-38683718

RESUMO

Sleep is vital to our daily activity. Lack of proper sleep can impair functionality and overall health. While stress is known for its detrimental impact on sleep quality, the precise effect of pre-sleep stress on subsequent sleep structure remains unknown. This study introduced a novel approach to study the pre-sleep stress effect on sleep structure, specifically slow-wave sleep (SWS) deficiency. To achieve this, we selected forehead resting EEG immediately before and upon sleep onset to extract stress-related neurological markers through power spectra and entropy analysis. These markers include beta/delta correlation, alpha asymmetry, fuzzy entropy (FuzzEn) and spectral entropy (SpEn). Fifteen subjects were included in this study. Our results showed that subjects lacking SWS often exhibited signs of stress in EEG, such as an increased beta/delta correlation, higher alpha asymmetry, and increased FuzzEn in frontal EEG. Conversely, individuals with ample SWS displayed a weak beta/delta correlation and reduced FuzzEn. Finally, we employed several supervised learning models and found that the selected neurological markers can predict subsequent SWS deficiency. Our investigation demonstrated that the classifiers could effectively predict varying levels of slow-wave sleep (SWS) from pre-sleep EEG segments, achieving a mean balanced accuracy surpassing 0.75. The SMOTE-Tomek resampling method could improve the performance to 0.77. This study suggests that stress-related neurological markers derived from pre-sleep EEG can effectively predict SWS deficiency. Such information can be integrated with existing sleep-improving techniques to provide a personalized sleep forecasting and improvement solution.


Assuntos
Algoritmos , Eletroencefalografia , Entropia , Sono de Ondas Lentas , Humanos , Eletroencefalografia/métodos , Masculino , Feminino , Sono de Ondas Lentas/fisiologia , Adulto , Adulto Jovem , Estresse Psicológico/fisiopatologia , Ritmo alfa/fisiologia , Previsões , Ritmo beta/fisiologia , Ritmo Delta , Privação do Sono/fisiopatologia , Reprodutibilidade dos Testes
18.
Hum Brain Mapp ; 45(6): e26687, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38651629

RESUMO

The unprecedented increase in life expectancy presents a unique opportunity and the necessity to explore both healthy and pathological aspects of ageing. Electroencephalography (EEG) has been widely used to identify neuromarkers of cognitive ageing due to its affordability and richness in information. However, despite the growing volume of data and methodological advancements, the abundance of contradictory and non-reproducible findings has hindered clinical translation. To address these challenges, our study introduces a comprehensive workflow expanding on previous EEG studies and investigates various static and dynamic power and connectivity estimates as potential neuromarkers of cognitive ageing in a large dataset. We also assess the robustness of our findings by testing their susceptibility to band specification. Finally, we characterise our findings using functionally annotated brain networks to improve their interpretability and multi-modal integration. Our analysis demonstrates the effect of methodological choices on findings and that dynamic rather than static neuromarkers are not only more sensitive but also more robust. Consequently, they emerge as strong candidates for cognitive ageing neuromarkers. Moreover, we were able to replicate the most established EEG findings in cognitive ageing, such as alpha oscillation slowing, increased beta power, reduced reactivity across multiple bands, and decreased delta connectivity. Additionally, when considering individual variations in the alpha band, we clarified that alpha power is characteristic of memory performance rather than ageing, highlighting its potential as a neuromarker for cognitive ageing. Finally, our approach using functionally annotated source reconstruction allowed us to provide insights into domain-specific electrophysiological mechanisms underlying memory performance and ageing. HIGHLIGHTS: We provide an open and reproducible pipeline with a comprehensive workflow to investigate static and dynamic EEG neuromarkers. Neuromarkers related to neural dynamics are sensitive and robust. Individualised alpha power characterises cognitive performance rather than ageing. Functional annotation allows cross-modal interpretation of EEG findings.


Assuntos
Eletroencefalografia , Envelhecimento Saudável , Humanos , Eletroencefalografia/métodos , Envelhecimento Saudável/fisiologia , Idoso , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Adulto Jovem , Envelhecimento Cognitivo/fisiologia , Biomarcadores , Rede Nervosa/fisiologia , Ondas Encefálicas/fisiologia , Ritmo alfa/fisiologia , Memória/fisiologia , Envelhecimento/fisiologia , Idoso de 80 Anos ou mais
19.
Behav Brain Res ; 469: 115003, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38642862

RESUMO

BACKGROUND: Executive functioning deficits are central to established neuropsychological models of ADHD. Oscillatory activity, particularly the alpha rhythm (8-12 Hz) has been associated with cognitive impairments in ADHD. However, most studies to date examined such neural mechanisms underlying executive dysfunction in children and adolescents with ADHD, raising the question of whether and to what extent those ADHD-related working memory impairments are still present in adults. To this end, the current study aimed to investigate the role of alpha event-related decreases (ERD) during working memory processes in adults with and without ADHD. METHODS: We collected electroencephalographic (EEG) data from 85 adults with a lifetime diagnosis of ADHD and 105 controls (aged 32-64), while they performed a continuous performance (CPT) and a spatial delayed response working memory task (SDRT). Time-frequency and independent component analysis (ICA) was used to identify alpha (8-12 Hz) clusters to examine group and condition effects during the temporal profile of sustained attention and working memory processes (encoding, maintenance, retrieval), loads (low and high) and trial type (go and nogo). RESULTS: Individuals with ADHD exhibited higher reaction time-variability in SDRT, and slower response times in SDRT and CPT, despite no differences in task accuracy. Although working memory load was associated with stronger alpha ERD in both tasks and both groups (ADHD, controls), we found no consistent evidence for attenuated alpha ERD in adults with ADHD, failing to replicate effects reported in children. In contrast, when looking at the whole sample, the correlations of alpha power during encoding with inattention and hyperactivity-impulsivity symptoms were significant, replicating prior findings in children with ADHD, but suggesting an alternate source for these effects in adults. CONCLUSIONS: Our results corroborate the robustness of alpha as a marker of visual attention and suggest that occipital alpha ERD normalizes in adulthood, but with unique contributions of centro-occipital alpha ERD, suggesting a secondary source. This implies that deviations in processes other than previously reported visuospatial cortex engagement may account for the persistent symptoms and cognitive deficits in adults with a history of ADHD.


Assuntos
Ritmo alfa , Transtorno do Deficit de Atenção com Hiperatividade , Atenção , Memória de Curto Prazo , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Memória de Curto Prazo/fisiologia , Masculino , Feminino , Adulto , Ritmo alfa/fisiologia , Atenção/fisiologia , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , Eletroencefalografia , Função Executiva/fisiologia , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia
20.
Brain Struct Funct ; 229(5): 1225-1242, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38683212

RESUMO

The neurobiology of Autism Spectrum Disorder (ASD) is hypothetically related to the imbalance between neural excitation (E) and inhibition (I). Different studies have revealed that alpha-band (8-12 Hz) activity in magneto- and electroencephalography (MEG and EEG) may reflect E and I processes and, thus, can be of particular interest in ASD research. Previous findings indicated alterations in event-related and baseline alpha activity in different cortical systems in individuals with ASD, and these abnormalities were associated with core and co-occurring conditions of ASD. However, the knowledge on auditory alpha oscillations in this population is limited. This MEG study investigated stimulus-induced (Event-Related Desynchronization, ERD) and baseline alpha-band activity (both periodic and aperiodic) in the auditory cortex and also the relationships between these neural activities and behavioral measures of children with ASD. Ninety amplitude-modulated tones were presented to two groups of children: 20 children with ASD (5 girls, Mage = 10.03, SD = 1.7) and 20 typically developing controls (9 girls, Mage = 9.11, SD = 1.3). Children with ASD had a bilateral reduction of alpha-band ERD, reduced baseline aperiodic-adjusted alpha power, and flattened aperiodic exponent in comparison to TD children. Moreover, lower raw baseline alpha power and aperiodic offset in the language-dominant left auditory cortex were associated with better language skills of children with ASD measured in formal assessment. The findings highlighted the alterations of E / I balance metrics in response to basic auditory stimuli in children with ASD and also provided evidence for the contribution of low-level processing to language difficulties in ASD.


Assuntos
Estimulação Acústica , Ritmo alfa , Córtex Auditivo , Transtorno do Espectro Autista , Magnetoencefalografia , Humanos , Transtorno do Espectro Autista/fisiopatologia , Feminino , Córtex Auditivo/fisiopatologia , Masculino , Criança , Ritmo alfa/fisiologia , Potenciais Evocados Auditivos/fisiologia , Percepção Auditiva/fisiologia , Eletroencefalografia
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