Vagal sensory neurons mediate the Bezold–Jarisch reflex and induce syncope

Nature, Journal Year: 2023, Volume and Issue: 623(7986), P. 387 - 396

Published: Nov. 1, 2023

Visceral sensory pathways mediate homeostatic reflexes, the dysfunction of which leads to many neurological disorders

Language: Английский

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Strength of low-frequency EEG phase entrainment to external stimuli is associated with fluctuations in the brain’s internal state

eNeuro, Journal Year: 2025, Volume and Issue: unknown, P. ENEURO.0064 - 24.2024

Published: Jan. 8, 2025

The brain attends to environmental rhythms by aligning the phase of internal oscillations. However, factors underlying fluctuations in strength this entrainment remain largely unknown. In present study we examined whether low-frequency EEG rhythmic stimulus sequences varied with pupil size and posterior alpha-band power, thought reflect arousal level excitability cortical areas, respectively. We recorded scalp while participants carried out an intermodal selective attention task, which they were instructed attend a sequence visual or auditory stimuli ignore other perceptual modality. As expected, intertrial coherence (ITC), measure strength, was larger for task-relevant than task-irrelevant Across experiment, alpha power strongly linked each other. Interestingly, ITC tracked both variables: associated increase sequence, whereas decrease sequences. Exploratory analyses showed that temporal relation between emerged time periods around maxima minima. These results indicate endogenous sources contribute distinctly entrainment. Significance statement Fluctuations state powerfully shape perception external stimuli. Understanding physiological signatures is crucial understand how selectively switches content. Here studied two attentional state, pupil-linked band, activity Our reveal common dissociable influences these at slow scales. Furthermore, measuring including as covariates statistical models can help studies focusing on provides new evidence direct influence

Language: Английский

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Noradrenergic modulation of rhythmic neural activity shapes selective attention

Trends in Cognitive Sciences, Journal Year: 2021, Volume and Issue: 26(1), P. 38 - 52

Published: Nov. 16, 2021

Language: Английский

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Coupling of pupil- and neuronal population dynamics reveals diverse influences of arousal on cortical processing

eLife, Journal Year: 2022, Volume and Issue: 11

Published: Feb. 8, 2022

Fluctuations in arousal, controlled by subcortical neuromodulatory systems, continuously shape cortical state, with profound consequences for information processing. Yet, how arousal signals influence population activity detail has so far only been characterized a few selected brain regions. Traditional accounts conceptualize as homogeneous modulator of neural across the cerebral cortex. Recent insights, however, point to higher specificity effects on different components and Here, we provide comprehensive account relationships between fluctuations neuronal human brain. Exploiting established link pupil size central performed concurrent magnetoencephalographic (MEG) pupillographic recordings large number participants, pooled three laboratories. We found cascade relative peak timing spontaneous dilations: Decreases low-frequency (2–8 Hz) temporal lateral frontal cortex, followed increased high-frequency (>64 mid-frontal regions, monotonic inverted U intermediate frequency-range (8–32 occipito-parietal Pupil-linked also coincided widespread changes structure aperiodic component activity, indicative excitation-inhibition balance underlying microcircuits. Our results novel basis studying modulation cognitive computations circuits.

Language: Английский

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Rhythms in cognition: The evidence revisited

European Journal of Neuroscience, Journal Year: 2022, Volume and Issue: 55(11-12), P. 2991 - 3009

Published: June 1, 2022

Brain activity abounds with rhythmic patterns (Capilla et al., 2021; Groppe 2013; Keitel & Gross, 2016) that reflect ongoing fluctuations of neuronal excitability (Adrian Matthews, 1934; Bishop, 1932). These rhythms can be described as oscillations cycle through phases at specific frequencies and a certain strength or amplitude (Figure 1). Attempts to account for the functional relevance have gone from associating cognitive function X Y more comprehensive understanding role brain in human everyday experience behaviour (Buzsáki Draguhn, 2004; Fries, 2015; Lakatos 2019; Wang, 2010). accounts support simple, yet fundamental idea: Cognitive functions themselves may intrinsically rhythmic. "The scanning apparatus should intrinsic period operation which identifiable performance brain. [...] In fact, it has order frequency appropriate alpha rhythm brain, shown electroencephalograms. We suspect this is associated form perception, partakes nature sweep rhythm, like process television apparatus." Theories derived these early ideas been reiterated over past 90 years. During time, research focussed on variations framework claiming processes depend offered wealth empirical evidence (Schroeder 2010; VanRullen, 2016; VanRullen Koch, 2003). Rhythmic sampling, implemented rhythms, proposed underlies not only perception but also attention (VanRullen 2007), memory (Staresina 2015), language (Giraud Poeppel, 2012). Linking cognition sampling particularly attractive because allows using global mechanistic principles bridge two different levels explanation: normal function, involves activity, experiences. addition, leaves open possibility actively intervening external stimulation either advance theory, example, close causal (see section 'Can we manipulate take control cognition?'), develop applications clinical interventions, such rehabilitation, brain-computer interfaces. The field, however, immune controversy. available does unequivocally assumed visual processing (Benwell 2017; Chaumon Busch, 2014; Fekete 2018; O'Hare, 1954; Ruzzoli van Diepen Van Walsh, 1952), various theoretical inconsistencies highlighted (Fekete White, 2018). For instance, exact implicated often differ between studies task and/or stimulus characteristics (Chen 2020; Ho Merholz 2022; Ronconi see table 2019), difficult reconcile any simple model fixed, discrete temporal 'frames' (White, Additionally, effect sizes showing periodicity behavioural neural measures tend small, hence line clear, all-or-nothing frame boundaries (Milton Pleydell-Pearce, 2018) utility real-life (Vigué-Guix 2020). Furthermore, literature suffers lack direct replications, pre-registered studies, data, code sharing (Garrett-Ruffin Niso Pavlov 2021), well low statistical power (Button 2013). Finally, publication bias favour statistically significant results distorted undermined reliability published (Szucs Ioannidis, 2017). Despite extensive research, existence remain intensely debated, idea continues attract vast interest. Special Issue, called methodologically principled irrespective their outcome, would contribute clarifying if, under conditions, observed. addition 26 original articles (including conceptual replications), received reviews, methodological advances, position papers. Following our aim re-visit cognition, evaluated primary outcomes 23 tested hypothesis directly. A split picture emerged 11 reporting supportive 12 others null inconclusive findings Figure 2). Within context, here review 36 publications Issue an emphasis how each contribution informs questions controversies wider cognition. doing so, cluster contributions around prevalent topics – Does operate rhythmically? And if processes? majority come influence outcomes. Below, summarise previous lines discuss relevant Issue. Numerous demonstrated by probing time intervals relative reference event. Provided are distributed across wide-enough range sampled densely within range, resulting course submitted spectral analysis rhythmicity. This approach new (e.g., Latour, 1967; Purushothaman 2000) become increasingly popular last decade Dugué Fiebelkorn Landau 2012; Senoussi 2019). refer reader Kienitz al. (2021) overview experimental paradigms employed study during attentive vision both non-human primates. behaviour, debate surrounds potential dissociations frequencies. Michel addressed topic information up down theta (4–7 Hz) (8–12 rhythms. participants performed orientation judgement after non-informative cue (50% validity) indicated target location. observed precision oscillated invalidly cued targets, whilst guess rate validly targets. suggest distinct roles potentially subserving attentional fluctuations. However, authors suggested environmental likely drives spatial resolution, rather than strict succession perceptual snapshots blind gaps 'up' 'down' respectively. possible frequencies, degree fixed depends demands participant state remains unclear. regard, Balestrieri (2021, issue) showed interplay working memory. Rhythms detection were maintenance simultaneous task. Interestingly, was modulated load, oscillating ~7.5 Hz versus 5 high respectively, suggesting might depending allocation limited resources another Morrow Samaha whether occurs alpha-band (Chakravarthi Sokoliuk 2016), capitalising motion-related illusions: flash-lag Fröhlich effect. Indeed, according recently (K. A. Schneider, 2018), supported series 'perceptual moments', duration individual differences illusions. hypothesised effects driven endogenous peak participants, then magnitude illusion correlated individuals. successfully induced illusions all found no correlation Bayesian favoured single underlying oscillatory mechanism could Plöchl examined auditory modality. Their included visual, auditory, bimodal conditions task, closely replicated seminal Fries (2012). Specifically, they capitalised reset (in modality) automatically drive one (left vs. right) streams events uncued locations. fluctuated counter phase attended locations, confirming supramodal processing. modality entirely earlier finding where alpha-range (9 response decision making (Ho combined dichotic oddball paradigm test violating sensory expectations made novel observation stimuli played non-anticipated ear induce subsequent theta-range (7.6 accuracy. update representations following violations expectations. concluded that, although rhythmicity corroborated (growing) number special considerations analytical necessary Brookshire, 2021). need chosen, require large trials participants. On note, der Werf unable replicate (Fiebelkorn Helfrich modified Egly-Driver (Egly 1994) detecting appear end (i.e., location) other space-based, non-cued bar, equidistant bar (object-based, location). No pattern accuracy locations level predictive validity, though exploratory did reveal ~7–8 when cues moderately informative. commentary al.'s study, proposes despite being comparable (Helfrich per condition replication too reliably detect further suggests purely data limiting combining simultaneously recorded electrophysiology (but ten Oever 2022, issue, Fiebelkorn's commentary). Magneto- electroencephalography (M/EEG) allow investigating activity. They enable analyses performance, detection, parameters (phase amplitude) presentation. Most M/EEG revolve question pre-stimulus affect attempting specific, previously untested conditions. EEG presented detected targets rhythmically counter-phase predicted modalities. Benwell challenging letter identification measure subjective awareness trial. confirmed reports (also By contrast, had accuracy, again replicating 1952). Similarly, Michail discrimination corresponding phase. unique aspect experiment long 2.5 s. Accordingly, speculate less lasting several cycles. Sheldon Mathewson set out post-stimulus likelihood guessing. reproduced precisely analysed error distribution models yield separate estimates Conceptually, similar who 'Rhythmicity behaviour'). (Mathewson 2009; Fakche 2022), performance. Instead, 2–7 activities Zazio issue), turn, clear behaviour. resembled (Busch 2009), reported Using MEG source analysis, stimulus-evoked inversely related occipito-temporal areas, whereas localised occipital prefrontal areas. Whilst assessed analysing Es (2020, used vector machine decode (counter/clockwise) signal. classification along theta/alpha frontal eye field parietal cortex contralateral grating stimulus. reflected (reaction times), leaving unknown. Gaillard Ben Hamed neurophysiological argue seems continuously regions alternates periodically center periphery parieto-frontal networks. two-stage positing combination continuous interact conscious percepts (Herzog Vigué-Guix attempted demonstrate interesting features stand section. First, aimed Callaway Yeager (1960), papers looking into idea. closed-loop analyse real-time (bright LED flashes) selectively rhythm. Second, kept eyes closed throughout experiment, amplified facilitated extracting its comparably small sample demonstrating level. reliable estimation parameter managed present accordingly, onset times participant. putative sizable enough practical relevance, signal interface applications. Along phase, recent investigated instantaneous within- between-participant integration temporally proximal (Samaha Postle, 2015) multisensory (audiovisual) (Cecere Keil Senkowski, 2017), theory cycles (VanRullen, 2016). London (2022, extend audiovisual supra-threshold stimuli. occipito-parietal electrodes increased sensitivity, found. results, those (Buergers Noppeney, cast doubt notion determining factor sensitivity perception. provided reviewed thus far provide answer way Behavioural issue frequently perhaps surprising contrasts suggestion (Fiebelkorn, 2021, given represents measurement question. tasks appears quite robust, (see, e.g., D. Schneider (Zazio Therefore, markedly weaker compared effects. aligns Benwell, Keitel, Notably, even subset considered attempts (Plöchl Der least very designs (van mixed. Replication extension key will critical development (Pavlov valuable examples. It crucial methodologies optimised 2022). flaws (such power), important validated replications. ideally trial numbers) terms overall size. collaborative run labs (Open Science Collaboration, 2015). Another future step derive hypotheses existing theories about tasks, states (and not). 1932) predicts is, excitability. arguably case short durations contrast feature longer (Michail Mathewson, issue). challenge define benchmark 'just works', stimuli, trusted fields neuroscience developed conventional eliciting interest, capture (Theeuwes, 1992), cueing (Carrasco, 2011), markers (Ngiam Establishing standard vantage point chart determine affects Manipulating periodic tool sampling. As Quigley reports, dates back Adrian Matthews (1934) Walter (1954), light light-induced responses synchronisation inputs since termed 'entrainment'. entrainment remained pervasive drew strengths major routes: explanatory functions, versatility technique experimenters and, later on, interventionists. Regarding power, Dynamic Attending Theory, posits internal oscillators rhythms) synchronise (Jones Boltz, 1989; Henry Herrmann, 2014). Once established, synchronised cycling optimal cortical coincide upcoming facilitates Lakatos, 2009). widely promoted general interactions input (Lakatos Tavano emblematic crucially underlie ability tune segment understand speech Rimmele Hauswald 2020, From perspective experimenters, versatile method directly manipulating Next stimulation, magnetic electrical non-invasive (NIBS) (Thut, Schyns, 2011). prospect influencing inspired interventions pathological please Tichko (2020) gamma-frequency (40 attempt counteract pathophysiologies linked Alzheimer's disease (Iaccarino strong integrating music-based currently therapy. enthusiastically overall, unclear, implementing applies circumscribed situations. One significance benefits beyond regularities input. implements selective (Calderone 2013), facilitate behaviourally providing periods Barne predictably recurring (here: tone frequency) lead higher predictable features, embedded regular sequences. interleaved instructed compare them probe brief retention interval. Although find benefit non-rhythmic de Graaf Duecker, W. M. Lin, Oetringer, Rassili Ordin, Sun nor pre-probe templates period, cortices intermittent pre-activation anticipation anticipatory anti-phasic activation supports puts maximally excitable (potential) delivery. Moreover, self-sustain ceases. Lin three experiments versions pitch total 181 occurring discriminated faster accurately out-of-phase. first experiments, low-frequency 1–3 Hz. paradigm, Hickok (2015) in-phase easily, entrainment. findings. After amplitude-modulated noise, responded tones constant noise pre-target noise. some periodicities consistently Saberi Hickok, Ordin presenting sequence (linguistic) syllables (non-linguistic) natural sounds similarly affected intermediately sound. neither type exceeded irregular Further hinted reactio

Language: Английский

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Pupil size reflects activation of subcortical ascending arousal system nuclei during rest

eLife, Journal Year: 2023, Volume and Issue: 12

Published: June 27, 2023

Neuromodulatory nuclei that are part of the ascending arousal system (AAS) play a crucial role in regulating cortical state and optimizing task performance. Pupil diameter, under constant luminance conditions, is increasingly used as an index activity these AAS nuclei. Indeed, task-based functional imaging studies humans have begun to provide evidence stimulus-driven pupil-AAS coupling. However, whether there such tight coupling during rest not clear. To address this question, we examined simultaneously acquired resting-state fMRI pupil-size data from 74 participants, focusing on six nuclei: locus coeruleus, ventral tegmental area, substantia nigra, dorsal median raphe nuclei, cholinergic basal forebrain. Activation all was optimally correlated with pupil size at 0-2 s lags, suggesting spontaneous changes were almost immediately followed by corresponding BOLD-signal AAS. These results suggest occur states can be noninvasive general Importantly, nature appears vastly different relatively slow canonical hemodynamic response function has been characterize task-related

Language: Английский

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Pupil size reveals arousal level fluctuations in human sleep

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Feb. 28, 2025

Abstract Recent animal research has revealed the intricate dynamics of arousal levels that are important for maintaining proper sleep resilience and memory consolidation. In humans, changes in level believed to be a determining characteristic healthy pathological but tracking fluctuations been methodologically challenging. Here we measured pupil size, an established indicator levels, by safely taping right eye open during overnight tested whether size affects cortical response auditory stimulation. We show change as function events across different temporal scales. particular, our results inversely related occurrence spindle clusters, marker resilience. Additionally, found prior stimulation influence evoked response, most notably delta power, several restorative regenerative functions sleep. Recording provides insights into interplay between oscillations.

Language: Английский

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Microsaccades are directed toward the midpoint between targets in a variably cued attention task

Proceedings of the National Academy of Sciences, Journal Year: 2023, Volume and Issue: 120(20)

Published: May 8, 2023

Reliable, noninvasive biomarkers that reveal the internal state of a subject are an invaluable tool for neurological diagnoses. Small fixational eye movements, called microsaccades, candidate biomarker thought to reflect subject's focus attention [Z. M. Hafed, J. Clark, VisionRes.42, 2533-2545 (2002); R. Engbert, Kliegl, VisionRes.43, 1035-1045 (2003)]. The linkage between direction microsaccades and has mainly been demonstrated using explicit unambiguous attentional cues. However, natural world is seldom predictable rarely provides information. Thus, useful must be robust such changes in environmental statistics. To determine how well visual-spatial across behavioral contexts, we analyzed these movements monkeys performing conventional change detection task. task included two stimulus locations variable cue validities blocks trials. Subjects were adept at task, showing precise graded modulations visual subtle target better faster when was more reliable [J. P. Mayo, H. Maunsell, Neurosci. 36, 5353 (2016)]. over tens thousands found no difference microsaccade cued variability high nor hit miss Instead, made toward midpoint locations, not individual targets. Our results suggest should interpreted with caution may measure covert spatial complex viewing conditions.

Language: Английский

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Double Dissociation of Spontaneous Alpha-Band Activity and Pupil-Linked Arousal on Additive and Multiplicative Perceptual Gain

Journal of Neuroscience, Journal Year: 2024, Volume and Issue: 44(19), P. e1944232024 - e1944232024

Published: March 28, 2024

Perception is a probabilistic process dependent on external stimulus properties and one's internal state. However, which states influence perception via what mechanisms remain debated. We studied how spontaneous alpha-band activity (8–13 Hz) pupil fluctuations impact visual detection confidence across contrast levels (i.e., the response function, CRF). In human subjects of both sexes, we found that low prestimulus alpha power induced an “additive” shift in CRF, whereby stimuli were reported present more frequently at all levels, including zero false alarms). Conversely, size had “multiplicative” effect such occurring during large (putatively corresponding to higher arousal) perceived as increased. Signal modeling reveals changes criteria equally CRF but not sensitivity ( d ′), whereas pupil-linked arousal modulated sensitivity, particularly for contrasts. Interestingly, positively correlated, meaning some may be mediated by fluctuations. pupil-independent still additive criterion effect. Our data imply boosts factor, rather than multiplicative scaling responses, profile captures arousal. suggest have dissociable effects behavior. Alpha reflects baseline level excitability, can vary independent

Language: Английский

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Beyond linear neural envelope tracking: a mutual information approach

Journal of Neural Engineering, Journal Year: 2023, Volume and Issue: 20(2), P. 026007 - 026007

Published: Feb. 22, 2023

Objective.The human brain tracks the temporal envelope of speech, which contains essential cues for speech understanding. Linear models are most common tool to study neural tracking. However, information on how is processed can be lost since nonlinear relations precluded. Analysis based mutual (MI), other hand, detect both linear and gradually becoming more popular in field Yet, several different approaches calculating MI applied with no consensus approach use. Furthermore, added value techniques remains a subject debate field. The present paper aims resolve these open questions.Approach.We analyzed electroencephalography (EEG) data participants listening continuous analyses models.Main results.Comparing approaches, we conclude that results reliable robust using Gaussian copula approach, first transforms standard Gaussians. With this analysis valid technique studying Like models, it allows spatial interpretations processing, peak latency analyses, applications multiple EEG channels combined. In final analysis, tested whether components were response by removing all data. We robustly detected single-subject level analysis.Significance.We demonstrate processes way. Unlike detects such relations, proving its addition, retains characteristics an advantage when complex (nonlinear) deep networks.

Language: Английский

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