Biology subjects

Keitel, A.

Publications and source records attributed to Keitel, A..

18 recordsLinked to original sources

bioRxiv2026

Top-down influences on neural music processing: preference, enjoyment and familiarity influence neural tracking and brain rhythms differently

Music enjoyment and familiarity are closely related but often confounded in studies of neural music processing. Here, we investigated their distinct contributions to cortical oscillatory activity and neural tracking of music using electroencephalography (EEG). Thirty-two participants listened to self-selected all-time favourite songs, recent favourite songs, and tempo-matched songs from disliked genres. This novel paradigm dissociated familiarity from enjoyment by including highly enjoyed songs that differed in familiarity. Spectral power and cortical tracking (using Mutual Information) were analysed using linear mixed-effects models with enjoyment and familiarity ratings. Familiarity was associated with increased left-frontal alpha power, whereas enjoyment predicted increased theta and beta power, demonstrating distinct oscillatory signatures for these dimensions. An interaction revealed that the positive relationship between enjoyment and theta power was strongest for highly familiar music. Cortical tracking analyses showed that greater enjoyment was associated with reduced delta-band tracking, with a significant interaction indicating that this negative relationship was present for highly familiar songs but not for less familiar songs. These findings indicate that enjoyment and familiarity differentially shape neural responses to music and highlight the importance of modelling both factors to disentangle their distinct effects on neural activity during music listening.

neuroscience↗

bioRxiv2026

Cortical Tracking of Speech and Music Predicts Reading Ability in Adults

Cortical tracking of acoustic features is essential for the neural processing of continuous stimuli such as speech and music. For example, it has been shown that children with dyslexia show atypical cortical tracking. This tracking may therefore reflect a fundamental auditory temporal processing mechanism supporting literacy more generally. In the current pre-registered study, we tested the hypothesis that cortical tracking of speech and music predicts reading ability in healthy young adults (N = 32), evaluated through a lexical decision task. Participants first completed an online session in which they performed a lexical decision task to assess their reading skills. This was followed by an electroencephalography (EEG) session, in which participants listened to a naturalistic short story and a music track. Using mutual information, we showed that neural activity aligned to both speech and music across a wide range of frequencies. Interestingly, cortical tracking was stronger for speech at very low frequencies, while it was stronger for music at higher frequencies. Critically, cortical tracking predicted reaction times in the lexical decision task in a frequency-dependent manner: stronger delta-band tracking ([~]1-3 Hz) for both speech and music was associated with faster reaction times, whereas stronger alpha-band tracking ([~]12 Hz) for speech was associated with slower reaction times. These findings remained significant even when controlling for stimulus type, age, musical experience and reading enjoyment. These results suggest that cortical tracking of speech and music reflect a domain-general temporal processing mechanism that is associated with reading ability beyond stimulus-specific features, and beyond development. These findings advance the neurobiological underpinnings of literacy and could potentially be leveraged for developing new reading interventions.

neuroscience↗

bioRxiv2026

Pupil- and gaze dynamics track emotion content in natural speech

Cortical tracking of speech features is a well-established marker of continuous speech processing, but far less is known about listeners ocular responses to speech rhythm. Ocular responses are central to active sensing models in the auditory domain, where motor recruitment guides temporal speech prediction and attention allocation, potentially shaped by non-rhythmic cues, such as emotions. Here, we ask whether listeners pupil response and eye movements track the acoustic speech signals and to what extent this tracking is modulated by emotion-related top-down factors, including subjective emotion ratings, mood, and trait empathy. In a validation study (N = 100), participants passively listened to two TED talks and intermittently rated segments on valence (negative-positive) and arousal (low-high). This suggested substantial variability in valence and arousal across speech segments in both talks. In the second study (N = 41), participants completed the same task while pupillometry and electrooculography (EOG) were recorded. Mutual information was used to quantify speech tracking in pupil dilation, along with horizontal and vertical eye movements. All ocular signals significantly tracked speech at low frequencies. High-arousal speech was associated with stronger pupil tracking but weaker vertical and horizontal EOG tracking. Negative speech valence was linked to stronger tracking in pupil and vertical eye-movement signals. Interactions between the speech-emotion dimensions, as well as their interactions with listeners mood, further shaped these effects, giving rise to distinct patterns across ocular measures. Taken together, our findings provide evidence that ocular activity dynamically aligns to the temporal structure of natural speech and that this tracking is sensitive to both stimulus-driven and listener-dependent emotional factors.

physiology↗

bioRxiv2025

Benefits of Music Training for Learning to Read: Evidence from Cortical Tracking of Speech in Children

Musical training has long been argued to boost early phonological and reading abilities. Cortical tracking of speech (CTS) has been proposed as a mechanism for this music-to-literacy transfer. In this study, we examined how musical training shapes CTS in young readers and whether it facilitates literacy benefits. In a sample of 57 children aged 5-9, musical training was linked to enhanced reading and phonological awareness (PA). EEG during story listening revealed that higher left-hemispheric and lower right-hemispheric CTS were also associated with higher reading scores. However, children with higher musicality exhibited stronger reading skills at lower levels of left-hemispheric CTS, suggesting more adult-like speech analysis. Critically, PA mediated the relationship between musicality and reading: greater musicality was associated with stronger PA, which in turn predicted higher reading performance, independent of demographic and cognitive factors. These findings indicate that musical training supports literacy by enhancing PA and shaping left-lateralized speech processing.

neuroscience↗

bioRxiv2025

Endogenous auditory and motor brain rhythms predictindividual speech tracking

Slow, endogenous brain rhythms in auditory cortex are hypothesized to track acoustic amplitude modulations during speech comprehension. Temporal predictions from the motor system are thought to enhance this tracking. However, direct evidence for the involvement of endogenous auditory and motor brain rhythms is lacking. Combining magnetoencephalographic recordings with behavioral data, we here show that endogenous peak frequencies of individuals resting-state theta rhythm in superior temporal gyrus predict speech tracking during comprehension. Importantly, endogenous rates of speech motor areas predicted auditory-cortical speech tracking only in individuals with high auditory-motor synchronization profiles. Higher rates in the supplementary motor area, and lower rates in inferior frontal gyrus, predicted stronger tracking. These findings align with participants behavioral data and provide compelling support for oscillatory accounts of auditory-motor interactions during speech perception. Interestingly, working memory capacity predicted speech comprehension performance particularly in individuals with low auditory-motor synchronization profiles. The findings highlight two partially independent speech processing routes across individuals: an auditory-motor route, related to enhanced comprehension performance, and an auditory working-memory route.

neuroscience↗

bioRxiv2023

Cortical and behavioural tracking of rhythm in music: Effects of pitch predictability, enjoyment, and expertise

The cortical tracking of stimulus features (such as the sound envelope) is a crucial neural requisite of how we process continuous music. We here tested whether cortical tracking of the beat, typically related to rhythm processing, is modulated by pitch predictability and other top-down factors. Participants listened to tonal (high pitch predictability) and atonal (low pitch predictability) music while undergoing EEG, and we analysed their cortical tracking of the acoustic envelope. Interestingly, cortical envelope tracking was stronger while listening to atonal than tonal music, likely reflecting listeners violated pitch expectations. Envelope tracking was also stronger with more expertise and enjoyment. Furthermore, we analysed cortical tracking of pitch surprisal (using IDyOM) and show that listeners expectations for tonal and atonal music match those computed by the IDyOM model, with higher surprisal (prediction errors) for atonal than tonal music. Behaviourally, we measured participants ability to tap along to the beat of tonal and atonal sequences in two experiments. In both experiments, finger-tapping performance was better in the tonal than the atonal condition, indicating a positive effect of pitch predictability on behavioural rhythm processing. Cortical envelope tracking predicted tapping performance for tonal music, as did pitch surprisal tracking for atonal music, indicating that conditions of high and low predictability might impose different processing regimes. We show that cortical envelope tracking, beyond reflecting musical rhythm processing, is modulated by pitch predictability, as well as musical expertise and enjoyment. Taken together, our results show various ways in which those top-down factors impact musical rhythm processing.

neuroscience↗

bioRxiv2022

Speech intelligibility changes the temporal evolution of neural speech tracking

Listening to speech with poor signal quality is challenging. Neural speech tracking of degraded speech has been used to advance the understanding of how brain processes and speech intelligibility are interrelated, however the temporal dynamics of neural speech tracking are not clear. In the present MEG study, we thereby exploited temporal response functions (TRFs) and generated signal-degraded speech to depict the temporal evolution of speech intelligibility modulation on neural speech tracking. In addition, we inter-related facets of neural speech tracking (e.g., speech envelope reconstruction, speech-brain coherence, and components of broadband coherence spectra) to endorse our findings in TRFs. Our TRF analysis yielded marked temporally differential effects of vocoding: reduction of intelligibility went along with large increases of early peak responses ([~]50-110 ms, M50TRF), but strongly reduced responses around 175-230 ms (M200TRF). For the late responses 315-380 ms (M350TRF), the maximum response occurred for degraded speech that was still comprehensible then declined with reduced intelligibility. Furthermore, we related the TRF components to our other neural "tracking" measures and found that M50TRF and M200TRF play a differential role in the shifting center frequency of the broadband coherence spectra. Overall, our study highlights the importance of time-resolved computation and parametrization of coherence spectra on neural speech tracking and provides a better understanding of degraded speech processing. HighlightsO_LIWe use MEG to show that speech intelligibility differentially impacts the temporal evolution of neural speech tracking. C_LIO_LITRF responses around 200 ms show the strongest relationship with behaviour. C_LIO_LIRelating TRF effects to parameterized coherence spectra using FOOOF suggests that M50TRF and M200TRF reflect shifts in which speech features are tracked over time. C_LI

neuroscience↗

bioRxiv2022

Explaining flexible continuous speech comprehension from individual motor rhythms

When speech is too fast, the tracking of the acoustic signal along the auditory pathway deteriorates, leading to suboptimal speech segmentation and decoding of speech information. Thus, speech comprehension is limited by the temporal constraints of the auditory system. Here we ask whether individual differences in auditory-motor coupling strength in part shape these temporal constraints. In two behavioral experiments, we characterize individual differences in the comprehension of naturalistic speech as function of the individual synchronization between the auditory and motor systems and the preferred frequencies of the systems. Obviously, speech comprehension declined at higher speech rates. Importantly, however, both higher auditory-motor synchronization and higher spontaneous speech motor production rates were predictive of better speech-comprehension performance. Furthermore, performance increased with higher working memory capacity (Digit Span) and higher linguistic, model-based sentence predictability - particularly so at higher speech rates and for individuals with high auditory-motor synchronization. These findings support the notion of an individual preferred auditory- motor regime that allows for optimal speech processing. The data provide evidence for a model that assigns a central role to motor-system-dependent individual flexibility in continuous speech comprehension.

neuroscience↗

bioRxiv2022

Visual and auditory cortices represent acoustic speech-related information during silent lip reading

Speech is an intrinsically multisensory signal and seeing the speakers lips forms a cornerstone of communication in acoustically impoverished environments. Still, it remains unclear how the brain exploits visual speech for comprehension and previous work debated whether lip signals are mainly processed along the auditory pathways or whether the visual system directly implements speech-related processes. To probe this question, we systematically characterized dynamic representations of multiple acoustic and visual speech-derived features in source localized MEG recordings that were obtained while participants listened to speech or viewed silent speech. Using a mutual-information framework we provide a comprehensive assessment of how well temporal and occipital cortices reflect the physically presented signals and speech-related features that were physically absent but may still be critical for comprehension. Our results demonstrate that both cortices are capable of a functionally specific form of multisensory restoration: during lip reading both reflect unheard acoustic features, with occipital regions emphasizing spectral information and temporal regions emphasizing the speech envelope. Importantly, the degree of envelope restoration was predictive of lip reading performance. These findings suggest that when seeing the speakers lips the brain engages both visual and auditory pathways to support comprehension by exploiting multisensory correspondences between lip movements and spectro-temporal acoustic cues. HighlightsO_LIVisual and auditory cortex represent unheard acoustic information during lip reading C_LIO_LIAuditory cortex emphasizes the acoustic envelope C_LIO_LIVisual cortex emphasizes a pitch signature C_LIO_LITracking of unheard features in auditory cortex is associated with behavior C_LI

neuroscience↗

bioRxiv2021

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

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

neuroscience↗

bioRxiv2021

Age-related decreases of cortical visuo-phonological transformation of unheard spectral fine-details

The integration of visual and auditory cues is crucial for successful processing of speech, especially under adverse conditions. Recent reports have shown that when participants watch muted videos of speakers, the phonological information about the acoustic speech envelope is tracked by the visual cortex. However, the speech signal also carries much richer acoustic details, e.g. about the fundamental frequency and the resonant frequencies, whose visuo-phonological transformation could aid speech processing. Here, we investigated the neural basis of the visuo-phonological transformation processes of these more fine-grained acoustic details and assessed how they change with ageing. We recorded whole-head magnetoencephalography (MEG) data while participants watched silent intelligible and unintelligible videos of a speaker. We found that the visual cortex is able to track the unheard intelligible modulations of resonant frequencies and the pitch linked to lip movements. Importantly, only the processing of intelligible unheard formants decreases significantly with age in the visual and also in the cingulate cortex. This is not the case for the processing of the unheard speech envelope, the fundamental frequency or the purely visual information carried by lip movements. These results show that unheard spectral fine-details (along with the unheard acoustic envelope) are transformed from a mere visual to a phonological representation. Aging affects especially the ability to derive spectral dynamics at formant frequencies. Since listening in noisy environments should capitalize on the ability to track spectral fine-details, our results provide a novel focus on compensatory processes in such challenging situations.

neuroscience↗

bioRxiv2021

Neural speech tracking shifts from the syllabic to the modulation rate of speech as intelligibility decreases

The most prominent acoustic features in speech are intensity modulations, represented by the amplitude envelope of speech. Synchronization of neural activity with these modulations is vital for speech comprehension. As the acoustic modulation of speech is related to the production of syllables, investigations of neural speech tracking rarely distinguish between lower-level acoustic (envelope modulation) and higher-level linguistic (syllable rate) information. Here we manipulated speech intelligibility using noise-vocoded speech and investigated the spectral dynamics of neural speech processing, across two studies at cortical and subcortical levels of the auditory hierarchy, using magnetoencephalography. Overall, cortical regions mostly track the syllable rate, whereas subcortical regions track the acoustic envelope. Furthermore, with less intelligible speech, tracking of the modulation rate becomes more dominant. Our study highlights the importance of distinguishing between envelope modulation and syllable rate and provides novel possibilities to better understand differences between auditory processing and speech/language processing disorders. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=160 SRC="FIGDIR/small/437033v1_ufig1.gif" ALT="Figure 1"> View larger version (23K): org.highwire.dtl.DTLVardef@6364adorg.highwire.dtl.DTLVardef@166daaeorg.highwire.dtl.DTLVardef@19eedd2org.highwire.dtl.DTLVardef@10f7aed_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2019

The frequency gradient of human resting-state brain oscillations follows cortical hierarchies

The human cortex is characterized by local morphological features such as cortical thickness, myelin content and gene expression that change along the posterior-anterior axis. We investigated if these structural gradients are associated with a similar gradient in a prominent feature of brain activity - namely the frequency of brain oscillations. In resting-state MEG recordings from healthy participants (N=187), we found that the strongest peak frequency in a brain area decreases significantly, gradually and robustly along the posterior-anterior axis following the global hierarchy from early sensory to higher-order areas. This spatial gradient of peak frequency was significantly anticorrelated with the cortical thickness of corresponding areas representing a proxy of the cortical hierarchical level. This result indicates that the intrinsic resonance frequency decreases systematically from early sensory to higher-order areas and establishes a new structure-function relationship pertaining to brain oscillations as a core organizational principle that may underlie hierarchical specialization in the brain.

neuroscience↗

bioRxiv2019

Data-driven classification of spectral profiles reveals brain region-specific plasticity

Congenital blindness has been shown to result in behavioral adaptation and neuronal reorganization, but the underlying neuronal mechanisms are largely unknown. Brain rhythms are characteristic for anatomically defined brain regions and provide a putative mechanistic link to cognitive processes. In a novel approach, using magnetoencephalography resting state data of congenitally blind and sighted humans, deprivation-related changes in spectral profiles were mapped to the cortex using clustering and classification procedures. Altered spectral profiles in visual areas suggest changes in visual alpha-gamma band inhibitory-excitatory circuits. Remarkably, spectral profiles were also altered in auditory and right frontal areas showing increased power in theta-to-beta frequency bands in blind compared to sighted individuals, possibly related to adaptive auditory and higher-cognitive processing. Moreover, occipital alpha correlated with microstructural white matter properties extending bilaterally across posterior parts of the brain. We provide evidence that visual deprivation selectively modulates spectral profiles, possibly reflecting structural and functional adaptation.

neuroscience↗

bioRxiv2019

Largely distinct networks mediate perceptually-relevant auditory and visual speech representations

Visual speech is an integral part of communication, but it remains unclear whether information carried by lip movements is represented in the same brain regions that mediate acoustic speech comprehension. Our ability to understand acoustic speech seems independent from that to understand visual speech, yet neuroimaging studies suggest that the neural representations largely overlap. Addressing this discrepancy, we tested where the brain represents acoustically and visually conveyed word identities in a full-brain MEG study. Our analyses dissociate cerebral representations that merely reflect the physical stimulus from those that also predict comprehension, and suggest that these overlap only in specific temporal and frontal regions. Moreover, representations predictive of auditory and visual comprehension converge only in angular and inferior frontal regions. These results provide a neural explanation for the behavioural dissociation of acoustic and visual speech comprehension and suggest that cerebral representations encoding word identities may be more modality-specific than often upheld.

neuroscience↗

bioRxiv2019

Degraded auditory and visual speech affects theta synchronization and alpha power differently

Understanding degraded speech, e.g. following a hearing damage, can pose a challenge. Previous attempts to quantify speech intelligibility in neural terms have usually focused on one of two measures, namely low-frequency speech-brain synchronization or alpha power modulations. However, reports have been mixed concerning the modulation of these measures, an issue aggravated by the fact that they have normally been studied separately. Using a parametric speech degradation approach, we present MEG studies that overcome this shortcoming. In a first study, participants listened to unimodal auditory speech with three different levels of degradation (original, 7-channel and 3-channel vocoding). Intelligibility declined with declining clarity, implemented by fewer vocoding channels but was still intelligible to some extent even for the lowest clarity level used (3-channel vocoding). Low- frequency (1-7 Hz) speech tracking suggested a u-shaped relationship with strongest effects for the medium degraded speech (7-channel) in bilateral auditory and left frontal regions. To follow up on this finding, we implemented three additional vocoding levels (5-channel, 2- channel, 1-channel) in a second MEG study. Using this wider range of degradation, the speech-brain synchronization showed a similar pattern for the degradation levels used in the first study but further shows that when speech becomes unintelligible, synchronization declines again. The relationship differed for alpha power, which continued to decrease across vocoding levels reaching a floor effect for 5-channel vocoding. Predicting subjective intelligibility based on models either combining both measures or each measure alone, showed superiority of the combined model. Our findings underline that speech tracking and alpha power are modified differently by the degree of degradation of continuous speech but together contribute to the subjective understanding of speech.

neuroscience↗

bioRxiv2018

Stimulus-driven brain rhythms within the alpha band: The attentional-modulation conundrum

Two largely independent research lines use rhythmic sensory stimulation to study visual processing. Despite the use of strikingly similar experimental paradigms, they differ crucially in their notion of the stimulus-driven periodic brain responses: One regards them mostly as synchronised (entrained) intrinsic brain rhythms; the other assumes they are predominantly evoked responses (classically termed steady-state responses, or SSRs) that add to the ongoing brain activity. This conceptual difference can produce contradictory predictions about, and interpretations of, experimental outcomes. The effect of spatial attention on brain rhythms in the alpha-band (8 - 13 Hz) is one such instance: alpha-range SSRs have typically been found to increase in power when participants focus their spatial attention on laterally presented stimuli, in line with a gain control of the visual evoked response. In nearly identical experiments, retinotopic decreases in entrained alpha-band power have been reported, in line with the inhibitory function of intrinsic alpha. Here we reconcile these contradictory findings by showing that they result from a small but far-reaching difference between two common approaches to EEG spectral decomposition. In a new analysis of previously published human EEG data, recorded during bilateral rhythmic visual stimulation, we find the typical SSR gain effect when emphasising stimulus-locked neural activity and the typical retinotopic alpha suppression when focusing on ongoing rhythms. These opposite but parallel effects suggest that spatial attention may bias the neural processing of dynamic visual stimulation via two complementary neural mechanisms.\n\nSIGNIFICANCE STATEMENTAttending to a visual stimulus strengthens its representation in visual cortex and leads to a retinotopic suppression of spontaneous alpha rhythms. To further investigate this process, researchers often attempt to phase-lock, or entrain, alpha through rhythmic visual stimulation under the assumption that this entrained alpha retains the characteristics of spontaneous alpha. Instead, we show that the part of the brain response that is phase-locked to the visual stimulation increased with attention (in line with steady-state evoked potentials), while the typical suppression was only present in non-stimulus-locked alpha activity. The opposite signs of these effects suggest that attentional modulation of dynamic visual stimulation relies on two parallel cortical mechanisms - retinotopic alpha suppression and increased temporal tracking.

neuroscience↗

bioRxiv2017

Speech tracking in auditory and motor regions reflects distinct linguistic features

AbstractDuring online speech processing, our brain tracks the acoustic fluctuations in speech at different time-scales. Previous research has focussed on generic time-scales (for example, delta or theta bands) that are assumed to map onto linguistic features such as prosody or syllables. However, given the high inter-subject variability in speaking patterns, such a generic association between the time-scales of brain activity and speech properties can be ambiguous. Here, we analyse speech tracking in source-localised magnetoencephalographic data by directly focusing on time-scales extracted from statistical regularities in the speech material. This revealed widespread tracking at the time-scales of phrases (0.6 - 1.3 Hz), words (1.8 - 3 Hz), syllables (2.8 - 4.8 Hz), and phonemes (8 - 12.4 Hz). Importantly, when examining the relevance for single-trial comprehension, we found stronger tracking for correctly comprehended trials in the left premotor cortex at the phrasal scale, and in left middle temporal cortex at the word scale. Control analyses using generic bands confirmed that these effects were specific to the stimulus-tailored speech regularities. Furthermore, we found that the phase at the phrasal time-scale coupled to beta-power in motor areas. This cross-frequency coupling likely mediates the comprehension effect in the motor system, and implies top-down temporal prediction in speech perception. Together, our results reveal specific functional and perceptually relevant roles of distinct entrainment processes along the auditory-motor pathway. These processes act concurrently at time-scales within the traditional delta band and highlight the role of neural tracking mechanisms that reflect the temporal characteristics of speech.

neuroscience↗