Causal functional maps of brain rhythms in working memory

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(14)

Published: March 27, 2024

Human working memory is a key cognitive process that engages multiple functional anatomical nodes across the brain. Despite plethora of correlative neuroimaging evidence regarding architecture, our understanding critical hubs causally controlling overall performance incomplete. Causal interpretation requires testing following safe, temporal, and controllable neuromodulation specific nodes. Such experiments became available in healthy humans with advance transcranial alternating current stimulation (tACS). Here, we synthesize findings 28 placebo-controlled studies (in total, 1,057 participants) applied frequency-specific noninvasive neural oscillations examined neurotypical adults. We use computational meta-modeling method to simulate each intervention realistic virtual brains test reported behavioral outcomes against stimulation-induced electric fields different brain Our results show stimulating anterior frontal medial temporal theta occipitoparietal gamma rhythms leads significant dose-dependent improvement task performance. Conversely, prefrontal modulation detrimental Moreover, found distinct spatial expression subbands, where changes followed orbitofrontal high-theta low-theta modulation. Finally, all these are driven by accuracy rather than processing time measures. These provide fresh view mechanisms, complementary research, propose hypothesis-driven targets for clinical treatment deficits.

Language: Английский

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Network Segregation and Integration Changes in Healthy Aging: Evidence From EEG Subbands During the Visual Short‐Term Memory Binding Task

European Journal of Neuroscience, Journal Year: 2025, Volume and Issue: 61(3)

Published: Feb. 1, 2025

ABSTRACT Working memory, which tends to be the most vulnerable cognitive domain aging, is thought depend on a functional brain network for efficient communication. The dynamic communication within this represented by segregation and integration. This study aimed investigate healthy aging examining age effect outcomes of graph theory analysis during visual short‐term memory binding (VSTMB) task. VSTMB tasks rely integration features are less sensitive semantic verbal strategies. Effects neuropsychological test scores, along with EEG graph‐theoretical integration, global organization metrics in frequencies from delta gamma band were investigated. Neuropsychological assessment showed low sensitivity as measure age‐related changes. results indicated that architecture changed more effectively middle age, while effectiveness appears vanish or show compensatory mechanisms elderly. These differences further found related scores. first demonstrate working across broad range.

Language: Английский

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Neuroplastic effects of transcranial alternating current stimulation (tACS): from mechanisms to clinical trials

Frontiers in Human Neuroscience, Journal Year: 2025, Volume and Issue: 19

Published: March 12, 2025

Transcranial alternating current stimulation (tACS) is a promising non-invasive neuromodulation technique with the potential for inducing neuroplasticity and enhancing cognitive clinical outcomes. A unique feature of tACS, compared to other modalities, that it modulates brain activity by entraining neural oscillations an externally applied current. While many studies have focused on online effects during stimulation, growing evidence suggests tACS can induce sustained after-effects, which emphasizes long-term neurophysiological changes, essential therapeutic applications. In first part this review, we discuss how after-effects could be mediated four non-mutually exclusive mechanisms. First, spike-timing-dependent plasticity (STDP), where timing pre- postsynaptic spikes strengthens or weakens synaptic connections. Second, spike-phase coupling oscillation phase as mediators plasticity. Third, homeostatic plasticity, emphasizing importance operate within dynamic physiological ranges. Fourth, state-dependent highlights state in modulatory tACS. second applications trials targeting neurological psychiatric disorders, including major depressive disorder, schizophrenia, Parkinson’s disease, Alzheimer’s disease. Evidence repeated sessions, optimized individual oscillatory frequencies combined behavioral interventions, may result lasting enhance However, critical challenges remain, need personalized dosing, improved modeling, systematic investigation effects. conclusion, review mechanisms translational bridging basic neuroscience research optimize its use tool.

Language: Английский

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Human head models and populational framework for simulating brain stimulations

Scientific Data, Journal Year: 2025, Volume and Issue: 12(1)

Published: March 27, 2025

Abstract Noninvasive brain stimulation (NIBS) is pivotal in studying human brain-behavior relations and treating disorders. NIBS effectiveness relies on informed targeting of specific regions, a challenge due to anatomical differences between humans. Computational volumetric head modeling can capture individual effects enable comparison across population. However, most studies implementing use single-head model, ignoring morphological variability, potentially skewing interpretation, realistic precision. We present comprehensive dataset 100 models with variable tissue conductivity values, lead-field matrices, standard-space co-registrations, quality-assured segmentations provide large sample healthy adult variance. Leveraging the Human Connectome Project s1200 release, this powers population for target optimization, MEEG source simulations, advanced meta-analysis studies. performed quality assessment each mesh, which included semi-manual segmentation accuracy correction finite-element analysis measures. This will facilitate developments academic clinical research.

Language: Английский

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Transcranial alternating current stimulation for investigating complex oscillatory dynamics and interactions

International Journal of Psychophysiology, Journal Year: 2025, Volume and Issue: 212, P. 112579 - 112579

Published: May 1, 2025

Neural oscillations play a fundamental role in human cognition and behavior. While electroencephalography (EEG) related methods provide precise temporal recordings of these oscillations, they are limited their ability to generate causal conclusions. Transcranial alternating current stimulation (tACS) has emerged as promising non-invasive neurostimulation technique modulate neural which offers insights into functional relation Originally, tACS is applied between two or more electrodes at given frequency. However, recent advances have aimed apply different waveforms target specific oscillatory dynamics. This systematic review evaluates the efficacy non-standard applications designed investigate patterns beyond simple sinusoidal stimulation. We categorized approaches three key domains: (1) phase synchronization techniques, including in-phase, anti-phase, traveling wave stimulation; (2) non-sinusoidal tACS, applies alternative such composite, broadband triangular oscillations; (3) amplitude-modulated interference stimulation, allow for concurrent EEG deeper cortical targeting. number studies evidence added value procedures, other show opposing null findings. Crucially, most currently low, such, goal this highlight both promise limitations providing foundation future research neurostimulation.

Language: Английский

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Direct Comparison of EEG Resting State and Task Functional Connectivity Patterns for Predicting Working Memory Performance Using Connectome-Based Predictive Modeling

Brain Connectivity, Journal Year: 2025, Volume and Issue: unknown

Published: May 2, 2025

Background: The integration of machine learning with advanced neuroimaging has emerged as a powerful approach for uncovering the relationship between neuronal activity patterns and behavioral traits. While resting-state significantly contributed to understanding neural basis cognition, recent fMRI studies suggest that task-based paradigms may offer superior predictive power cognitive outcomes. However, this hypothesis never been tested using electroencephalography (EEG) data. Methods: We conducted first experimental comparison models built on high-density EEG data recorded during both an auditory working memory task. Multiple processing pipelines were employed ensure robustness reliability. Model performance was evaluated by computing Pearson correlation coefficient predicted observed scores, supplemented mean absolute error root square metrics each model configuration. Results: Consistent prior findings, yielded slightly better modeling than Both conditions demonstrated high accuracy, peak correlations values reaching r = 0.5. Alpha beta band functional connectivity strongest predictors performance, followed theta gamma bands. Additionally, choice parcellation atlas method influenced results, highlighting importance methodological considerations. Conclusion: Our findings support advantage over in predicting aligning with. study underscores critical role frequency-specific choices performance. These insights should guide future designs neuroscience.

Language: Английский

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Physiology-Inspired Bifocal Fronto-Parietal tACS for Working Memory Enhancement

Heliyon, Journal Year: 2024, Volume and Issue: 10(18), P. e37427 - e37427

Published: Sept. 1, 2024

Language: Английский

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Attention improvement to transcranial alternating current stimulation at gamma frequency over the right frontoparietal network: a preliminary report

Acta Neuropsychiatrica, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 5

Published: Oct. 2, 2024

Abstract Applying transcranial alternating current stimulation (tACS) at 40 Hz to the frontal and parietal regions, either unilaterally (left or right) bilaterally, can improve cognitive dysfunctions. This study aimed explore influence of tACS gamma frequency over right fronto-parietal (FP) region on attention. The analysis is based retrospective data from a clinical intervention. We administered test variables attention (TOVA; visual mode) 44 participants with various neuropsychiatric diagnoses before after 12 sessions treatment. Alternating currents 2.0 mA were delivered electrode positions F4 P4, following 10–20 EEG convention, for 20 mins in each session. observed significant improvement across 3 indices TOVA, including reduction variability reaction time ( p = 0.0002), increase d-Prime (separability targets non-targets; 0.0157), decrease commission error rate 0.0116). mean RT omission largely remained unchanged. Artificial injection FP network may function, especially domains consistency performance, target/non-target discrimination, inhibitory control.

Language: Английский

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Attention improvement to transcranial alternating current stimulation at gamma frequency over the right frontoparietal network: a preliminary report

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: June 11, 2024

Abstract Objective Applying transcranial alternating current stimulation (tACS) at 40 Hz to the frontal and parietal regions can improve cognitive dysfunctions. This study aimed explore influence of tACS gamma frequency over right fronto-parietal (FP) region on attention. Methods We administered Test Variables Attention (TOVA; visual mode) 44 participants with various neuropsychiatric diagnoses before after 12 sessions treatment. Alternating currents 2.0 mA were delivered electrode positions F4 P4, following 10-20 EEG convention, for 20 minutes in each session. Results observed significant improvement across 3 indices TOVA, including reduction variability reaction time (RT; P =0.0002), increase d-Prime (separability targets non-targets; =0.0157), decrease commission error rate ( =0.0116). The mean RT omission largely remained unchanged. Conclusion Artificial injection FP network may attention function, especially domains consistency performance, target/non-target discrimination, inhibitory control.

Language: Английский

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Transcranial Direct Current Stimulation over the Posterior Parietal Cortex Increases Non-target Retrieval during Visual Working Memory

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: June 18, 2024

Abstract Accurate visual working memory (VWM) requires precise content-context binding. Previous studies have revealed a close relationship between the posterior parietal cortex (PPC) and feature binding during VWM, this study further examined their causal through three transcranial direct current stimulation (tDCS) experiments. In Experiment 1 ( N = 57), participants underwent sessions of tDCS separately, including PPC stimulation, occipital sham completed series delayed estimation tasks for orientations before after stimulation. Results showed that over selectively prolonged recall response time (RT) increased probability non-target responses (a.k.a. failure binding). 2 29), combining metacognition task, we investigated whether effects on RT were attributed to more mis-binding (i.e., self-reported "remembered" in responses) or informed guessing (participants "forgotten" responses). We replicated main findings 1, also observed greater trials than while comparable rates these two types trials. 3 28), then specifically influenced retrieval process by using change detection task. found did not influence recognition accuracy. Together, provides evidence supporting involvement VWM retrieval. Significance Statement Visual enables humans temporarily store information, which accurate items unique context. Accumulating posited is closely related process, relationship. Through strictly within-subject well-designed non-invasive neural experiments, error VWM. Moreover, changes modulated individual only occurred instead recognition. our results provided strong causally involved

Language: Английский

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