Beta to theta power ratio in EEG periodic components as a potential biomarker in mild cognitive impairment and Alzheimer’s dementia

Alzheimer s Research & Therapy, Год журнала: 2023, Номер 15(1)

Опубликована: Авг. 7, 2023

Abstract Background Alzheimer’s dementia (AD) is associated with electroencephalography (EEG) abnormalities including in the power ratio of beta to theta frequencies. EEG studies mild cognitive impairment (MCI) have been less consistent identifying such abnormalities. One potential reason not excluding aperiodic components, which are cognition than periodic components. Here, we investigate whether and components disrupted differently AD or MCI vs. healthy control (HC) individuals a based beta/theta differentiates better from HC groups on full spectrum. Methods Data were collected 44 (mean age (SD) = 69.1 (5.3)), 114 72.2 (7.5)), 41 75.7 (6.5)) participants. Aperiodic spectrum compared among three groups. Receiver operating characteristic curves obtained via logistic regression classifications used distinguish Last, explored relationships between performance ratios Results did differ In contrast, participants showed an increase relative powers for delta, theta, gamma decrease when As predicted, group differed (Bonferroni corrected p -value 0.036) measured over occipital region. Classifiers distinguished participants, outperformed classifiers EEG. Beta/theta comparable their association cognition. Conclusions contrast analysis, periodic-based analysis shows that different individuals. Focusing without other biological markers neurodegenerative diseases could result more reliable findings separate aging, would be valuable designing preventative interventions.

Язык: Английский

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Resting-state EEG signatures of Alzheimer's disease are driven by periodic but not aperiodic changes

Neurobiology of Disease, Год журнала: 2023, Номер 190, С. 106380 - 106380

Опубликована: Дек. 17, 2023

Electroencephalography (EEG) has shown potential for identifying early-stage biomarkers of neurocognitive dysfunction associated with dementia due to Alzheimer's disease (AD). A large body evidence shows that, compared healthy controls (HC), AD is power increases in lower EEG frequencies (delta and theta) decreases higher (alpha beta), together slowing the peak alpha frequency. However, pathophysiological processes underlying these changes remain unclear. For instance, recent studies have that apparent shifts from high low can be driven either by frequency specific periodic or rather non-oscillatory (aperiodic) 1/f slope spectrum. Hence, clarify mechanism(s) alterations AD, it necessary account both aperiodic characteristics signal. Across two independent datasets, we examined whether resting-state linked reflect true oscillatory (periodic) changes, (non-oscillatory) signal, a combination both. We found strong are purely nature, at beta (AD < HC) leading + beta) / ratios AD. Aperiodic features did not differ between HC. By replicating findings cohorts, provide robust pathophysiology against changes. therefore neural dynamics emphasize robustness signatures, which may further used as prognostic interventional targets future clinical investigations.

Язык: Английский

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Fundamentals of sleep regulation: Model and benchmark values for fractal and oscillatory neurodynamics

Progress in Neurobiology, Год журнала: 2024, Номер 234, С. 102589 - 102589

Опубликована: Март 1, 2024

Homeostatic, circadian and ultradian mechanisms play crucial roles in the regulation of sleep. Evidence suggests that ratios low-to-high frequency power electroencephalogram (EEG) spectrum indicate instantaneous level sleep pressure, influenced by factors such as individual sleep-wake history, current stage, age-related differences brain topography characteristics. These effects are well captured reflected spectral exponent, a composite measure constant ratio periodogram, which is scale-free exhibits lower interindividual variability compared to slow wave activity, potentially serving suitable standardization reference measure. Here we propose an index homeostasis based on reflecting membrane hyperpolarization and/or network bistability central nervous system humans. In addition, advance idea U-shaped overnight deceleration oscillatory fast spindle frequencies marks biological night, providing somnologists with EEG-index regulation. supporting this assertion comes from studies replacement, forced desynchrony protocols high-resolution analyses spindles. Finally, regulatory indicated recurrent, abrupt shifts dominant frequencies, ranges signifying non-rapid eye movement non-spindle oscillations – rapid phases cycles. Reconsidering indicators fundamental processes framework new Fractal Oscillatory Adjustment Model (FOAM) offers appealing opportunity bridge gap between two-process model clinical somnology.

Язык: Английский

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Assessing cortical excitability with electroencephalography: A pilot study with EEG-iTBS

Brain stimulation, Год журнала: 2024, Номер 17(2), С. 176 - 183

Опубликована: Янв. 27, 2024

BackgroundCortical excitability measures neural reactivity to stimuli, usually delivered via Transcranial Magnetic Stimulation (TMS). Excitation/inhibition balance (E/I) is the ongoing equilibrium between excitatory and inhibitory activity of circuits. According some studies, E/I could be estimated in-vivo non-invasively through modeling electroencephalography (EEG) signals termed 'intrinsic excitability' measures. Several have been proposed (phase consistency in gamma band, sample entropy, exponent power spectral density 1/f curve, index extracted from detrend fluctuation analysis, alpha power). Intermittent theta burst stimulation (iTBS) primary motor cortex (M1) a non-invasive neuromodulation technique allowing controlled focal enhancement TMS cortical stimulated hemisphere.ObjectiveInvestigating what extent estimates scale with how they relate each other.MethodsM1 (TMS) several resting state EEG recordings were assessed before after iTBS cohort healthy subjects.ResultsEnhancement M1 excitability, as measured motor-evoked potentials (MEPs), phase high band correlated other. Other showed expected results, but no correlation or strong other.ConclusionsEEG offer an intriguing opportunity map non-invasively, spatio-temporal resolution stimulus independent approach. While different may reflect diverse excitatory-inhibitory circuits, spatial synchrony measure that best captures changes cortex.

Язык: Английский

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Aperiodic components of local field potentials reflect inherent differences between cortical and subcortical activity

Cerebral Cortex, Год журнала: 2024, Номер 34(5)

Опубликована: Май 1, 2024

Abstract Information flow in brain networks is reflected local field potentials that have both periodic and aperiodic components. The 1/fχ component of the power spectra tracks arousal correlates with other physiological pathophysiological states. Here we explored activity human thalamus basal ganglia relation to simultaneously recorded cortical activity. We elaborated on parameterization implemented by specparam (formerly known as FOOOF) avoid parameter unidentifiability obtain independent more easily interpretable parameters. This allowed us seamlessly fit without an knee, a captures change slope component. found exponent χ, which reflects decay frequency, correlated Parkinson’s disease symptom severity. Interestingly, no knee was detected from thalamus, pallidum, or subthalamic nucleus, exhibited significantly lower than cortex. These differences were replicated epilepsy patients undergoing intracranial monitoring included thalamic recordings. consistently lack all subcortical recordings may reflect cytoarchitectonic and/or functional differences. Significance statement can be modeled produce useful reproducible indices neural refined widely used phenomenological model for extracting parameters (namely exponent, offset knee), cortical, ganglia, potentials, unique cohorts movement disorders patients. motor cortex higher Parkinson's severe symptoms, suggesting features potential electrophysiological biomarkers symptoms. Remarkably, conspicuous signals compared those neocortex.

Язык: Английский

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Posture‐Dependent Modulation of Interoceptive Processing in Young Male Participants: A Heartbeat‐Evoked Potential Study

European Journal of Neuroscience, Год журнала: 2025, Номер 61(4)

Опубликована: Фев. 1, 2025

ABSTRACT Interoception, the internal perception of bodily states such as heartbeat and hunger, plays a crucial role in shaping cognitive emotional states. Since postural control affects processing, exploring effects on interoception could help uncover neural mechanisms underlying its cognition emotion. In this study, we aimed to investigate how different postures affect by using heartbeat‐evoked potentials (HEPs), which reflect cortical processing cardiac signals. Two experiments were conducted; Experiment 1 involved 47 healthy male participants comparing sitting standing postures, 2 24 stable unstable conditions. HEPs analyzed cluster‐based permutation analysis identify statistically significant spatiotemporal clusters. 1, clusters identified over central electrodes (Cz, C1, C2, FCz, FC1) within post‐R‐wave interval 304–572 ms, revealing significantly lower HEP amplitudes during compared [ W = 80, p < 0.001, r 0.62]. 2, t (20) 2.9, 0.0099, d Furthermore, found no correlations between changes physiological activity periodic aperiodic brain activity. These findings suggest differences modulate interoceptive with attenuating amplitudes, probably because redistribution attentional resources from somatosensory (proprioceptive) vestibular necessary for maintaining posture. This study provides insights into posture–interoception interaction.

Язык: Английский

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Oscillatory and Aperiodic Neural Activity Jointly Predict Language Learning

Journal of Cognitive Neuroscience, Год журнала: 2022, Номер 34(9), С. 1630 - 1649

Опубликована: Янв. 1, 2022

Abstract Memory formation involves the synchronous firing of neurons in task-relevant networks, with recent models postulating that a decrease low-frequency oscillatory activity underlies successful memory encoding and retrieval. However, to date, this relationship has been investigated primarily face image stimuli; considerably less is known about correlates complex rule learning, as language. Furthermore, work shown nonoscillatory (1/ƒ) functionally relevant cognition, yet its interaction during learning remains unknown. Using spectral decomposition power-law exponent estimation human EEG data (17 women, 18 men), we show for first time 1/ƒ jointly influence word order rules miniature artificial language system. Flexible word-order were associated steeper slope, whereas fixed shallower slope. We also increased theta alpha power predicts relative flexible behavioral performance. Together, these results suggest plays an important role higher-order including processing, grammar modulated by different permutations, which manifest distinct profiles.

Язык: Английский

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The time-evolving epileptic brain network: concepts, definitions, accomplishments, perspectives

Frontiers in Network Physiology, Год журнала: 2024, Номер 3

Опубликована: Янв. 16, 2024

Epilepsy is now considered a network disease that affects the brain across multiple levels of spatial and temporal scales. The paradigm shift from an epileptic focus—a discrete cortical area which seizures originate—to widespread network—spanning lobes hemispheres—considerably advanced our understanding epilepsy continues to influence both research clinical treatment this multi-faceted high-impact neurological disorder. network, however, not static but evolves in time requires novel approaches for in-depth characterization. In review, we discuss conceptual basics theory critically examine state-of-the-art recording techniques analysis tools used assess characterize time-evolving human network. We give account on current shortcomings highlight potential developments towards improved management epilepsy.

Язык: Английский

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The Temporal Dynamics of Aperiodic Neural Activity Track Changes in Sleep Architecture

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Янв. 26, 2024

Abstract The aperiodic (1/f-like) component of electrophysiological data - whereby power systematically decreases with increasing frequency, as quantified by the exponent has been shown to differentiate sleep stages. Earlier work, however, typically focused on measuring across a narrow frequency range. In this we sought further investigate activity during extending these analyses broader ranges and considering alternate model definitions. This included ‘knees’ in component, which reflect bends spectrum, indicating change exponent. We also evaluate temporal dynamics sleep. To do so, analyzed from two sources: intracranial EEG (iEEG) 106 epilepsy patients high-density 17 healthy individuals, measured activity, explicitly comparing different forms. doing find that fitting broadband models incorporating ‘knee’ feature effectively captures sleep-stage-dependent differences well relate stage transitions responses external stimuli. particular, knee parameter shows stage-specific variation, suggesting an interpretation varying timescales These results demonstrate examining more complex reveals novel insights interpretations for understanding neural

Язык: Английский

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Aperiodic and Hurst EEG exponents across early human brain development: A systematic review

Developmental Cognitive Neuroscience, Год журнала: 2024, Номер 68, С. 101402 - 101402

Опубликована: Июнь 7, 2024

In electroencephalographic (EEG) data, power-frequency slope exponents (1/f_β) can provide non-invasive markers of in vivo neural activity excitation-inhibition (E:I) balance. E:I balance may be altered neurodevelopmental conditions; hence, understanding how 1/f β evolves across infancy/childhood has implications for developing early assessments/interventions. This systematic review (PROSPERO-ID: CRD42023363294) explored the maturation (0-26 yrs) resting-state EEG measures (aperiodic [AE], power law [PLE] and Hurst [HE] exponents), including studies containing ≥1 ≥10 typically participants. Five databases (including Embase Scopus) were searched during March 2023. Forty-two identified (Nparticipants=3478). Risk bias was assessed using Quality Assessment with Diverse Studies tool. Narrative synthesis HE data suggests non-stationary occurs throughout development. Age-related trends complex, rapid decreases AEs infancy heterogenous changes thereafter. Regionally, AE maxima shifted developmentally, potentially reflecting spatial maturing brain connectivity. work highlights importance further characterising development to better understand shapes cognitive

Язык: Английский

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