Stimulus-Induced Changes in 1/f-like Background Activity in EEG

Journal of Neuroscience, Год журнала: 2022, Номер 42(37), С. 7144 - 7151

Опубликована: Авг. 15, 2022

Research into the nature of 1/f-like, nonoscillatory electrophysiological activity has grown exponentially in recent years cognitive neuroscience. The shape this been linked to balance between excitatory and inhibitory neural circuits, which is thought be important for information processing. However, date, it not known whether presentation a stimulus induces changes parameters 1/f scalp recordings, separable from event-related potentials (ERPs). Here, we analyzed broadband human EEG both before after removing ERPs demonstrate their confounding effect, establish there are genuine stimulus-induced 1/f. Using data passive an active auditory task (n = 23, 61% female), found that post-event spectra 2 25 Hz differed significantly pre-event even frequency-content ERPs. Further, significant portion difference could accounted by rotational shift activity, manifesting as increase low decrease high frequencies. Importantly, magnitude was related attentional demands task. This change consistent with increased inhibition following onset, likely reflects disruption ongoing proportional processing demands. Finally, these findings contradict central assumption baseline normalization strategies time-frequency analyses, namely, background stationary across time. As such, they have far-reaching consequences relevant several subfields SIGNIFICANCE STATEMENT Interest functional role 1/f-like brain growing Yet, no study date demonstrated clear relationship investigating effects on its noninvasive recordings activity. demonstrate, first time, stimuli induce detectable at lower frequencies independent occurrence potentials. These suggest presence large-scale largest when novel, indicate analysis oscillations untenable. results cut

Язык: Английский

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Slope of the power spectral density flattens at low frequencies (<150 Hz) with healthy aging but also steepens at higher frequency (>200 Hz) in human electroencephalogram

Cerebral Cortex Communications, Год журнала: 2023, Номер 4(2)

Опубликована: Янв. 1, 2023

The power spectral density (PSD) of the brain signals is characterized by two distinct features: oscillations, which are represented as "bumps," and broadband aperiodic activity, that reduces in with increasing frequency slope falloff. Recent studies have shown a change activity healthy aging mental disorders. However, these analyzed slopes over limited range (<100 Hz). To test whether PSD affected wider disorder, we till 800 Hz electroencephalogram data recorded from elderly subjects (>49 years) who were (

Язык: Английский

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Event-induced modulation of aperiodic background EEG: Attention-dependent and age-related shifts in E:I balance, and their consequences for behavior

Imaging Neuroscience, Год журнала: 2023, Номер 2, С. 1 - 18

Опубликована: Дек. 4, 2023

Abstract The broadband shape of the EEG spectrum, summarized using slope a 1/fx function, is thought to reflect balance between excitation and inhibition in cortical regions (E:I balance). This an important characteristic neural circuits could inform studies aging, as older adults show relative deficit inhibitory activity. Thus far, no have leveraged event-related temporal dynamics activity better understand phases information processing, especially context aging. Here, for first time, we examined variations this during foreperiod cued flanker task younger (YA) (OA), with picture cues varying relevance, novelty, valence. We report biphasic change spectral after cue presentation, independent cue-elicited potentials (ERPs), initial period steeper (indicating inhibition, similar YA OA) followed by flattening excitation, OA). reduction steepness was associated lower performance greater congruency costs task. Finally, more novel reduced shift towards OA, partly restoring their E:I balance, diminishing costs. These findings demonstrate that spectrum varies dynamically manner predictive subsequent behavior. They also expand our understanding how communication shapes cognition OA has implications neuroscientific models cognitive processing age-related decline.

Язык: Английский

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The Heartbeat‐Evoked Potential in Young and Older Adults During Attention Orienting

Psychophysiology, Год журнала: 2025, Номер 62(4)

Опубликована: Апрель 1, 2025

ABSTRACT Cardiac cycle duration, or interbeat interval (IBI), is the period from one heartbeat to next. IBI changes cycle. Periods with longer are associated higher sensitivity external sensory stimuli (exteroception). Warning cues induce a state of attentive anticipation characterized by an increase in (anticipatory cardiac deceleration) and faster reaction times. Aging reduces induced warning response speed. However, it unclear which mechanism, if any, connects time. The heartbeat‐evoked potential (HEP) cortical evoked heartbeat, modulated attention stimuli. HEP might be affected mediate association between output processing. We investigated was as well spontaneous fluctuations IBI. To explore impact age‐related responses, we included young older people ( N = 33/29; 26/23 women; mean age 23/61 years). analyzed electroencephalograms electrocardiograms simultaneously acquired during auditory cued simple time go/no‐go tasks. cue did not significant HEP. Yet, (not locked cue) HEP, amplitude average group. on trial‐by‐trial basis, independent fluctuations. In conclusion, found no evidence that mediates effect orienting

Язык: Английский

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Simplified neurochaos learning architectures for data classification

Chaos An Interdisciplinary Journal of Nonlinear Science, Год журнала: 2025, Номер 35(6)

Опубликована: Июнь 1, 2025

Developing machine learning algorithms that can classify datasets with higher accuracy and efficiency is crucial in practical applications. Neurochaos (NL) a recently proposed algorithm inspired by the chaotic firing of neurons brain. NL has shown promise recent times both terms classification number samples needed for training. In this study, we propose novel simplification neurochaos reducing features also hyperparameters to be tuned. By using single feature neural traces (orbit generated map) only one hyperparameter, demonstrate significant boost run time while retaining comparable accuracy. This could either mean (Tracemean) or Fluctuation Index (FI) traces. The classifier itself simple cosine similarity (Tracemean ChaosNet, FI ChaosNet) any classical (ML) classifiers (Tracemean+ML, FI+ML). We compare performance these newly simplified on ten publicly available datasets. architectures study are able efficiently taking much less time. fact hyperparameter needs tuned ChaosNet makes them very attractive applications ease interpretability.

Язык: Английский

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COMPLEXITY-BASED ANALYSIS OF THE CORRELATION OF BRAIN AND HEART ACTIVITY IN YOUNGER AND OLDER SUBJECTS

Fractals, Год журнала: 2023, Номер 32(01)

Опубликована: Ноя. 30, 2023

Studying the activity of organs during aging is a very important research area. On other hand, simultaneous analysis activities various to understand how their are correlated. For first time, this analyzes brain-heart correlation in younger and older subjects. We analyzed sample entropy (SampEn) approximate (ApEn) EEG R-R signals (as heart rate variability (HRV)) participants while they sat comfortably an armchair with eyes open. The results indicated that subjects’ have greater values entropies than Therefore, as subjects age, become more complex. This can be extended investigate between physiological among different age groups.

Язык: Английский

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Cardiorespiratory rhythm-contingent trace eyeblink conditioning in elderly adults

Journal of Neurophysiology, Год журнала: 2024, Номер 131(5), С. 797 - 806

Опубликована: Март 27, 2024

Learning outcome is modified by the degree to which subject responds and pays attention specific stimuli. Our recent research suggests that presenting stimuli in contingency with a phase of cardiorespiratory rhythm might expedite learning. Specifically, expiration-diastole (EXP-DIA) beneficial for learning trace eyeblink conditioning (TEBC) compared inspiration-systole (INS-SYS) healthy young adults. The aim this study was investigate whether same holds true elderly adults (

Язык: Английский

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Event-Induced Modulation of Aperiodic Background EEG: Attention-Dependent and Age-Related Shifts in E:I balance, and Their Consequences for Behavior

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2023, Номер unknown

Опубликована: Апрель 14, 2023

Abstract The broadband shape of the EEG spectrum, summarized using a 1/ f x function, is thought to reflect balance between excitation and inhibition in cortical regions (E:I balance). This an important characteristic neural circuits could inform studies aging, as older adults show relative inhibitory activity deficit. Thus far, no have leveraged event-related temporal dynamics better understand phases information processing, especially context aging. Here, for first time, we examined variations this during foreperiod cued flanker task younger (YA) (OA), with picture cues varying relevance, novelty, valence. We report biphasic change spectral exponent (corresponding negative slopes log-log space) after cue presentation, independent cue-elicited ERPs, initial period increased negativity (indicating inhibition, similar YA OA) followed by decreased excitation, OA). decrease was associated lower performance greater congruency costs task. Finally, more novel reduced shift towards OA, partly restoring their E:I balance, diminishing costs. These findings demonstrate that spectrum varies dynamically manner predictive subsequent behavior. They also expand our understanding how communication shapes cognition OA implications neuroscientific models cognitive processing age-related decline.

Язык: Английский

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Age differentially modulates the cortical tracking of the lower and higher level linguistic structures during speech comprehension

Cerebral Cortex, Год журнала: 2023, Номер 33(19), С. 10463 - 10474

Опубликована: Авг. 11, 2023

Speech comprehension requires listeners to rapidly parse continuous speech into hierarchically-organized linguistic structures (i.e. syllable, word, phrase, and sentence) entrain the neural activities rhythm of different levels. Aging is accompanied by changes in processing, but it remains unclear how aging affects levels representation. Here, we recorded magnetoencephalography signals older younger groups when subjects actively passively listened which hierarchical sentence were tagged at 4, 2, 1 Hz, respectively. A newly-developed parameterization algorithm was applied separate periodically tracking from aperiodic component. We found enhanced lower-level (word-level) tracking, reduced higher-level (phrasal- sentential-level) offset compared with adults. Furthermore, observed attentional modulation on sentential-level being larger for than ones. Notably, neuro-behavior analyses showed that subjects' behavioral accuracy positively correlated reversely tracking. Overall, these results suggest less flexibility may underpin aging-related decline comprehension.

Язык: Английский

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Slope of the power spectral density flattens at low frequencies (<150 Hz) with healthy aging but also steepens at higher frequency (>200 Hz) in human electroencephalogram

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2023, Номер unknown

Опубликована: Фев. 15, 2023

Abstract Brain signals such as electroencephalogram (EEG) often show oscillations at various frequencies, which are represented distinct “bumps” in the power spectral density (PSD) of these signals. In addition, PSD also shows a reduction with increasing frequency, pertains to aperiodic activity and is termed “1/f” component. While change periodic brain healthy aging mental disorders has been reported, recent studies have shown slope factors well. However, only analysed slopes over limited frequency range (<100 Hz). To test whether affected wider disorder, we collected EEG data high sampling rate (2500 Hz) from large population elderly subjects (>49 years) who were (N=217) or had mild cognitive impairment (MCI; N=11) Alzheimer’s Disease (AD; N=5), till 800 Hz. Consistent previous studies, 1/f up ~150 Hz reduced aging. Surprisingly, found opposite higher frequencies (>200 Hz): increased age. This result was observed all electrodes, for both eyes open closed conditions, different reference schemes. Slopes not significantly MCI/AD compared age gender matched controls. Overall, our results constrain biophysical mechanisms that reflected pathological Significance Statement Aperiodic characterized by measuring spectrum flatten aging, suggesting an increase some sort “neural noise”. this flattening (<150 We Hz), happens: steepens occurs irrespective state referencing techniques. unchanged early (AD) their Our shed new light on properties neural noise neurophysiological processes affecting AD activity.

Язык: Английский

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