Biology subjects

Landau, A. N.

Publications and source records attributed to Landau, A. N..

At least 19 recordsLinked to original sources

bioRxiv2026

Supra second timing reflects oscillatory and aperiodic EEG dynamics

The perception of timing has been investigated across short and long timescales, with the latter usually underrepresented. Previous accounts of supra-second timing have often emphasised dedicated neural signals, yet whether timing performance over longer durations reflects specialised temporal mechanisms or domain-general neural excitability remains unclear. We examined this question in an interval reproduction task (2-4 s) using EEG, decomposing neural activity into oscillatory (alpha, theta) and aperiodic components and relating both to behavioural performance. At the neural level, separate analyses were performed on the interval encoding epoch and the following delay period. Time-resolved analyses revealed a coordinated decrease in posterior alpha power and aperiodic offset during interval encoding. In contrast, interval duration did not produce consistent modulation of oscillatory or aperiodic activity during the delay period, providing limited support for a workload-based account of time duration. Across participants, higher baseline alpha power and aperiodic offset were associated with better timing accuracy, whereas trial-by-trial fluctuations in aperiodic activity, and to a lesser extent alpha power, predicted single-trial reproductions. The results suggest that temporal behaviour in the supra-second range is shaped by domain-general neural activity sustaining goal-directed task engagement-- with oscillatory and aperiodic dynamics serving as complementary indices of this broader excitability state.

neuroscience↗

bioRxiv2026

Prediction Is Preserved but Long-Timescale Benefits Are Reduced in ADHD

Attention-deficit/hyperactivity disorder (ADHD) has been associated with atypical temporal processing across multiple cognitive domains. However, most evidence derives from simplified paradigms that isolate timing from spatial behaviour. Here, we examine how temporal prediction operates within a continuous, dynamic visual environment. Using the Dynamic Visual Search (DVS) task, we embedded spatiotemporal regularities into a sustained stream of visual events, allowing observers to implicitly learn and anticipate predictable targets. Continuous mouse tracking provided a fine-grained measure of action planning beyond discrete reaction time and accuracy metrics. Young adults diagnosed with ADHD (N=40) were compared to matched neurotypical controls (N=38). Both groups benefited from target predictability and reduced distractor load, indicating intact early spatiotemporal learning in ADHD. Across the duration of the task, however, the groups diverged. Neurotypical participants showed progressive increases in behavioural benefits from prediction, accompanied by increasingly direct and efficient mouse trajectories. In contrast, individuals with ADHD reached a plateau in prediction benefits midway through the experiment. Their performance remained stable, with minimal evidence of resource depletion, but did not show further optimisation based on learned regularities. These findings suggest that while prediction formation is preserved in ADHD, its progressive utilisation across longer timescales is attenuated. Rather than reflecting a primary deficit in learning or sustained attention, ADHD may involve altered long-timescale integration or weighting of predictive information in dynamic environments.

neuroscience↗

bioRxiv2025

Feel the Beat: The Impact of Rhythms on Dynamic Visual Search

Rhythms are everywhere - we encounter them daily within our environment and produce them regularly through our movements, speech and sensory systems. In both cognitive and clinical contexts, external rhythms have been shown to enhance performance when they are aligned with, predict, or entrain stimuli onsets or relevant moments in time. In this study, we aimed to understand the impact of external and internal rhythms on performance in a task devoid of rhythmic temporal structure. We thus investigated the differential impact of auditory beats (1-, 2-, 5-Hz, or no beat) on detection in a non-rhythmic, dynamic search task requiring the continuous deployment of attention. We additionally assessed whether the influence of auditory beats on detection was modulated by individuals rhythmic preferences as measured by their spontaneous motor tempo. Overall, we found that auditory rhythms enhanced visual task performance, even in the absence of rhythmic structure within the measured task, improving both detection accuracy and response speed. This enhancement was tempo-dependent, with the strongest facilitation observed at 2 Hz. The magnitude of the observed benefits varied with individuals spontaneous motor tempo, such that participants with slower SMTs exhibited the greatest performance benefits due to the presence of auditory rhythms. We propose that rhythmic stimulation may serve as a powerful scaffold for sustained performance in the context of dynamic and temporally unpredictable environments.

neuroscience↗

bioRxiv2025

From Individual to Shared Tempo: How Spontaneous Tempo Preferences Impact Joint Performance

Endogenous rhythmic structure is a key characteristic of our cognitive system, organizing both sensory processes and motor behavior. In the motor domain, recent studies demonstrated that individuals vary systematically in the spontaneous tempo of self-paced movement, exhibiting consistent tempo preferences across time, tasks, and cognitive demands. In our daily experience, we often need to perform with others, adjusting our motor signatures to support interpersonal coordination. The purpose of this study is to examine how individuals with distinct spontaneous tempi reconcile their personal tempo preferences with the need to synchronize during joint performance. To this end, we measured individuals spontaneous tempo across different days using three motor behaviors: tapping, walking, and bouncing. This design allowed us to examine both temporal consistency and cross-task consistency. Participants were then asked to perform these tasks together under two experimental conditions: (1) side-by-side, without explicit instructions to synchronize, and (2) with explicit instructions to synchronize their movements. Our findings replicate and extend recent work, demonstrating that individuals show stable rhythmic preferences across time, tasks, and interactive contexts. When performing together, two complementary patterns emerged. First, dyads converged on a common tempo around 2 Hz, reflecting a preferred tempo for joint rhythmic performance. Second, individuals retained a bias toward their own spontaneous tempo during joint performance, with faster or slower individuals performing correspondingly fast or slow within the range of dyadic tempo. Finally, individuals with more similar spontaneous tempi achieved greater synchrony and temporal stability when performing together. Thus, while individuals can flexibly adjust their spontaneous tempo to support joint action, personal tempo preferences remain a robust source of variability in how people perform and interact with others.

animal behavior and cognition↗

bioRxiv2025

Similarity in Spontaneous Tempo Impacts Flow Experience and Coordination Dynamics During Joint Performance

Individuals tend to perform simple rhythmic tasks at a characteristic tempo, known as their spontaneous motor tempo. This motor trait, whether one naturally moves at a faster or slower pace, has been implicated in the ability to perform with external rhythmic structure across various tasks and experimental settings. In daily life, external rhythms often emerge through social interaction, as we continuously adapt to and move with rhythms generated by others. While previous studies have shown that individuals with similar spontaneous tempi can synchronize better in structured tasks, the role of individuals spontaneous tempo in unstructured, dynamic social interactions remains untested. In the current study, we examined how individuals spontaneous tempo shapes interpersonal coordination and subjective experience during an open-ended, free-form dyadic movement task. We first assessed individuals tempo using a spontaneous tapping task. Then, we measured interpersonal coordination patterns, including synchrony and leader-follower dynamics using a joint improvisation task inspired by the mirror game. Specifically, we developed a novel platform, composed of large transparent touch screens that resemble a shared window, on which individuals could continuously improvise motion together in an intuitive and playful manner. Participants alternated between game rounds with a designated leader and game rounds of leaderless improvisation. Following the mirror game, we also measured individuals subjective experience using a flow questionnaire. We found that individuals with similar spontaneous tempi reported greater flow experience during joint performance. Furthermore, we found that individuals with similar spontaneous tempi tended to synchronize less and were more variable and dynamic in their coordination patterns, specifically during leaderless improvisation rounds. Finally, we found that flow experience was highest when a participants movement tempo during the mirror game aligned with their own spontaneous tempo, regardless of their partners. These findings highlight individual spontaneous tempo as a meaningful trait that shapes both coordination dynamics and subjective experience during creative joint performance.

animal behavior and cognition↗

bioRxiv2025

Computational Mechanisms of Temporal Anticipation in Perception and Action

To interact effectively with our surroundings, we rely on strategies to reduce uncertainty. One important source of information is temporal regularities, which enable us to form predictions about when events will occur, and through this, prepare for them in advance. Such preparation was shown to facilitate motor planning, yet the impact of temporal anticipation on perceptual acuity is unknown, and the cognitive computations underlying this process remain debated. To answer these questions, we administered a new difficult change discrimination task with variable anticipatory periods (N=142). We show that both perceptual sensitivity and motor responses are influenced by temporal structure. Using computational modelling, we show that the cognitive operation underlying this behavior is based on a logarithmic transformation of the event hazard rate (HR) and reveal a crucial role of temporal-estimation noise in shaping this computation, both when temporal information is encoded, and when it is decoded. Together, our results highlight the fundamental contribution of anticipation in directing behavior and advance our understanding of temporal processing in the brain.

neuroscience↗

bioRxiv2024

Universal rhythmic architecture uncovers distinct modes of neural dynamics

Understanding the organizing principles of brain activity can advance neurotechnology and medical diagnosis. Traditionally, brain activity has been viewed as consisting electrical field potentials oscillating at different frequency bands. However, emerging evidence suggests these oscillations can manifest as transient bursts rather than sustained rhythms. Here, we examine the hypothesis that rhythmicity (sustained vs. bursty) adds an additional dimension to brain organization. We segment neurophysiological spectra from 859 participants encompassing a dozen datasets across multiple species, recording techniques, ages 18-88, sexes, brain regions, and cognitive states in health and disease using a novel rhythmicity measure. Combined with simulations and brain stimulation, our results reveal a universal spectral architecture with two categories: high-rhythmicity bands exhibiting sustained oscillations and novel low-rhythmicity bands dominated by brief bursts. This universal architecture reflects stable modes of brain operation: sustained bands suitable for maintaining ongoing activity, and transient bands which can signal responses to change. Rhythmicity thus provides a powerful, replicable, and accessible feature-set for neurotechnology and diagnosis.

neuroscience↗

bioRxiv2024

A universal of speech timing: Intonation units form low frequency rhythms and balance cross-linguistic syllable rate variability

Intonation units (IUs) are a universal building-block of human speech. They are found cross-linguistically and are tied to important language functions such as the pacing of information in discourse and swift turn-taking. We study the rate of IUs in 48 languages from every continent and from 27 distinct language families. Using a novel analytic method to annotate natural speech recordings, we identify a low-frequency rate of IUs across the sample, with a peak at 0.6 Hz, and little variation between sexes or across the life span. We find that IU rate is only weakly related to speech rate quantified at the syllable level (SR), and crucially, that cross-linguistic variation in IU rate is smaller than cross-linguistic variation in SR. Since SR was shown to be inversely related to information density quantified at the syllable level, we suggest that across languages, IUs are more balanced than syllables in their information content.

animal behavior and cognition↗

bioRxiv2024

Neural evidence for action-related somatosensory predictions

The tactile consequences of self-initiated movements are thought to be predicted by a forward model, yet the precise neural implementation of these predictions remains unclear. In non- motor contexts, expectations are thought to activate sensory neurons tuned towards the expected stimulus. This acts as a predictive template against which afferent sensory input is compared. It is unclear whether forward model predictions have a similar neural instantiation. Here we employed time-resolved multivariate decoding on human electroencephalography (EEG) during self-generated movements to examine the content of predictive neural activity. Human participants performed index finger movements which were predictably paired with a vibration to either the index or ring finger of the opposite, passive hand. On some trials the tactile stimulus was unexpectedly omitted. Results revealed above-chance finger decoding in the pre-movement period supporting a predictive representation of expected stimulation location. As the movement approached, this predictive activity became similar to late-stage processing of a physical tactile stimulus. On omission trials, we found that despite the absence of afferent input, finger location could be decoded [~]120 ms after expected stimulus onset. This shows a stimulus-specific omission response. Together these findings indicate that self-generated movement pre-activates neurons tuned towards expected tactile consequences.

neuroscience↗

bioRxiv2024

A bounded accumulation model of temporal generalization outperforms existing models and captures modality differences and learning effects

Multiple systems in the brain track the passage of time and can adapt their activity to temporal requirements (Paton & Buonomano, 2018). While the neural implementation of timing varies widely between neural substrates and behavioral tasks, at the algorithmic level many of these behaviors can be described as bounded accumulation (Balc & Simen, 2024). So far, from the range of temporal psychophysical tasks, the bounded accumulation model has only been applied to temporal bisection, in which participants are requested to categorize an interval as "long" or "short" (Balc & Simen, 2014; Ofir & Landau, 2022). In this work, we extend the model to fit performance in the temporal generalization task, in which participants are required to categorize an interval as being the same or different compared to a standard, or reference, duration (Wearden, 1992). Previous models of performance in this task focused on either the group level or performance of highly trained animals (Birngruber et al., 2014; Church & Gibbon, 1982; Wearden, 1992). Whether the same models can fit performance from a few hundreds of trials of single participants, necessary for comparing performance across experimental manipulations, has not been tested. A drift-diffusion model with two decision boundaries fits the data of single participants better than the previous models. We ran two experiments, one comparing performance between vision and audition and another examining the effect of learning. We found that decision boundaries can be modified independently: While the upper boundary was higher in vision compared to audition, the lower boundary decreased with learning in the task.

neuroscience↗

bioRxiv2024

The representation of stimulus features during stable fixation and active vision

Predictive updating of an objects spatial coordinates from its retinotopic pre-saccadic to post-saccadic position contributes to stable visual perception. However, whether object features are predictively represented at the remapped location remains contested. Many previous studies showing evidence of feature remapping neglect the spatially invariant representation of features in the visual system. For example, feature-based attention boosts attended features across the entire visual field, potentially contributing to the maintenance of stimulus features across saccades. We set out to characterise the spatiotemporal dynamics of feature processing during stable fixation and active vision. To do so, we applied multivariate decoding methods to electroencephalography (EEG) data collected while participants viewed brief visual stimuli. Stimuli appeared at different locations across the visual field at either high or low spatial frequency (SF). During fixation, classifiers were trained to decode SF presented at one parafoveal location and cross-tested on SF from either the same, adjacent or more peripheral locations. When training and testing on the same location, SF was classified shortly after stimulus onset ([~]80 ms). Decoding of SF at locations farther from the trained location emerged later ([~]150-300 ms), with decoding latency modulated by eccentricity. This analysis provides a detailed time course for the spread of feature information across the visual field. Next, we investigated how active vision impacts the emergence of SF information. In the presence of a saccade, the decoding time of peripheral SF at parafoveal locations was accelerated, indicating predictive anticipation of SF due to the saccade. Crucially however, this predictive effect was not limited to the specific remapped location. Rather, peripheral SF was correctly classified, at an accelerated time course, at all parafoveal positions. This indicates a spatially coarse remapping of stimulus features during active vision, likely enabling a smooth transition on saccade landing. Significance StatementMaintaining a continuous representation of object features across saccades is vital for stable vision. In order to characterise the spatiotemporal dynamics of stimulus feature representation in the brain, we presented stimuli at a high and low spatial frequency at multiple locations across the visual field. Applying EEG-decoding methods we tracked the neural representation of spatial frequency during both stable fixation and active vision. Using this approach, we provide a detailed time course for the spread of feature information across the visual field during fixation. In addition, when a saccade is imminent, we discovered that the spread of feature information is expedited such that access to peripheral spatial frequency is accelerated.

neuroscience↗

bioRxiv2024

Motor preparation tracks decision boundary crossing in temporal decision-making

Interval timing, the ability of animals to estimate the passage of time, is thought to involve diverse neural processes rather than a single central "clock" (Paton & Buonomano, 2018). Each of the different processes engaged in interval timing follows a different dynamic path, according to its specific function. For example, attention tracks anticipated events, such as offsets of intervals (Rohenkohl & Nobre, 2011), while motor processes control the timing of the behavioral output (De Lafuente et al., 2024). Hence, different processes provide complimentary perspectives on mechanisms of time perception. The temporal bisection task, where participants categorize intervals as "long" or "short", is thought to rely on the same mechanisms as other perceptual decisions (Balc & Simen, 2014). In line with this hypothesis, we previously described an EEG potential that tracks the formation of decision following the end of the timed interval (Ofir & Landau, 2022). Here, we track the dynamics of motor preparation to investigate the formation of decision within the timed interval. In contrast to typical perceptual decisions, where motor plans for all response alternatives are prepared simultaneously (Shadlen & Kiani, 2013), we find that different temporal decisions develop sequentially. While preparation for "long" responses was already underway before interval offset, no preparation was found for "short" responses. Furthermore, within intervals categorized as "long", motor preparation was stronger at interval offset for faster responses. Our findings shed light on the unique dynamics of temporal decisions and demonstrate the importance of considering neural activity in timing tasks from multiple perspectives.

neuroscience↗

bioRxiv2023

Decoding Remapped Spatial Information in the Peri-Saccadic Period

It has been suggested that, prior to a saccade, visual neurons predictively respond to stimuli that will fall in their receptive fields after completion of the saccade. This saccadic remapping process is thought to compensate for the shift of the visual world across the retina caused by eye movements. To map the timing of this predictive process in the brain, we recorded neural activity using electroencephalography (EEG) during a saccade task. Participants made saccades between two fixation points while covertly attending to oriented gratings briefly presented at various locations on the screen. Data recorded during trials in which participants maintained fixation were used to train classifiers on stimuli in different positions. Subsequently, data collected during saccade trials were used to test for the presence of remapped stimulus information at the post-saccadic retinotopic location in the peri-saccadic period, providing unique insight into when remapped information becomes available. We found that the stimulus could be decoded at the remapped location [~]180 ms post-stimulus onset, but only when the stimulus was presented 100-200 ms before saccade onset. Within this range, we found that the timing of remapping was dictated by stimulus onset rather than saccade onset. We conclude that presenting the stimulus immediately before the saccade allows for optimal integration of the corollary discharge signal with the incoming peripheral visual information, resulting in a remapping of activation to the relevant post-saccadic retinotopic neurons. Significance StatementEach eye movement leads to a shift of the visual world across the retina, such that the visual input before and after the eye movement do not match. Despite this, we perceive the visual world as stable. A predictive mechanism known as saccadic remapping is thought to contribute to this stability. We use a saccade task with time-resolved EEG decoding to obtain a fine-grained analysis of the temporal dynamics of the saccadic remapping process. Probing different stimulus-saccade latencies and an array of stimulus locations, we identify when remapped information becomes available in the visual cortex. We describe a critical window in which feedforward visual information and the preparatory motor signals interact to allow for predictive remapping of a stimulus.

neuroscience↗

bioRxiv2023

Intonation Units in spontaneous speech evoke a neural response

Spontaneous speech is produced in chunks called Intonation Units (IUs). IUs are defined by a set of prosodic cues and occur in all human languages. Linguistic theory suggests that IUs pace the flow of information and serve as a window onto the dynamic focus of attention in speech processing. IUs provide a promising and hitherto unexplored theoretical framework for studying the neural mechanisms of communication, thanks to their universality and their consistent temporal structure across different grammatical and socio-cultural conditions. In this article, we identify a neural response unique to the boundary defined by the IU. We measured the EEG of participants who listened to different speakers recounting an emotional life event. We analyzed the speech stimuli linguistically, and modeled the EEG response at word offset using a GLM approach. We find that the EEG response to IU-final words differs from the response to IU-nonfinal words when acoustic boundary strength is held constant. To the best of our knowledge, this is the first time this is demonstrated in spontaneous speech under naturalistic listening conditions, and under a theoretical framework that connects the prosodic chunking of speech, on the one hand, with the flow of information during communication, on the other. Finally, we relate our findings to the body of research on rhythmic brain mechanism in speech processing by comparing the topographical distributions of neural speech tracking in model-predicted and empirical EEG. This qualitative comparison suggests that IU-related neural activity contributes to the previously characterized delta-band neural speech tracking.

neuroscience↗

bioRxiv2022

Perplexity about periodicity repeats perpetually: A response to Brookshire

Brookshire (2022) claims that previous analyses of periodicity in detection performance after a reset event suffer from extreme false-positive rates. Here we show that this conclusion is based on an incorrect implemention of a null-hypothesis of aperiodicity, and that a correct implementation confirms low false-positive rates. Furthermore, we clarify that the previously used method of shuffling-in-time, and thereby shuffling-in-phase, cleanly implements the null hypothesis of no temporal structure after the reset, and thereby of no phase locking to the reset. Moving from a corresponding phase-locking spectrum to an inference on the periodicity of the underlying process can be accomplished by parameterizing the spectrum. This can separate periodic from non-periodic components, and quantify the strength of periodicity.

neuroscience↗

bioRxiv2022

Rhythmic Modulation of Visual Discrimination is Dependent on Individuals' Spontaneous Motor Tempo

Rhythmic structure in our daily experience originates from various sources. It is generated endogenously and observed in spontaneous fluctuations in behaviour and performance. It can also arise exogenously from everyday stimuli, such as speech, motion and music. Here we examined how individual differences in spontaneous motor rhythms affect the tendency to use external rhythmic structure to guide perception. To measure individual differences in spontaneous rhythms of performance we utilized a spontaneous tapping task. To measure individual differences in perceptual rhythmic modulation we designed a visual discrimination task in which targets can appear either in-phase or out-of-phase with a preceding rhythmic stream of visual stimuli. We manipulated the tempo of the visual stream over different experimental blocks (0.77 Hz, 1.4 Hz, 2 Hz). We found that visual rhythmic stimulation modulates discrimination performance. The modulation was dependent on the tempo of stimulation, with maximal perceptual benefits for the slowest tempo of stimulation (0.77 Hz). Most importantly, the strength of modulation was also affected by individuals spontaneous motor tempo. Specifically, individuals with slower spontaneous tempi showed greater rhythmic modulation compared to individuals with faster spontaneous tempi. This discovery suggests that different tempi affect the cognitive system with varying levels of efficiency, and that self-generated rhythms impact our ability to utilize rhythmic structure in the environment for guiding perception and performance.

neuroscience↗

bioRxiv2020

Hello From the Other Side: Robust Contralateral Interference in Tactile Detection

Our sense of touch is unique in that our tactile receptors are spread across our body surface and constantly receive different inputs at the same time. These inputs vary in relevance according to our current goals, but there is little research on how simultaneous stimulation to different body sites affects the perception of touch. In this series of studies, we characterised how irrelevant tactile sensations across the body-midline affect tactile detection in a constantly-attended body site. Participants had to detect a target on their dominant index finger, while receiving irrelevant stimulation to another body site (homologous and non-homologous fingers, and the contralateral ankle). We document robust interference effects on all measured body-sites. Its impact on detection-performance was unaffected by body posture, exacerbated by the intensity of the irrelevant stimulation, and ameliorated by embedding a target-like signal in the irrelevant stimulation. In addition, we generalise our findings beyond the target stimulus (i.e., a vibration intensity decrement) and report similar effects when employing a target-increment. In light of our findings, we propose that tactile inputs may be pooled together early in the hierarchy of somatosensory processing, resulting in an integrated percept. The rules for integration across body sides are likely not described by a simple summation, but rather may be governed by more complex interactions between fingers and according to the corresponding perceived, as well as actual, intensities of the stimulation. HighlightsO_LIIrrelevant stimulation to a contralateral body site hinders tactile detection. C_LIO_LIWe show robust and early integration of sensory inputs from across body sides. C_LIO_LIThe amount of interference varies by the signal-to-noise in the irrelevant stimulation. C_LIO_LIInterference may result from cortical integration of bilateral tactile sensations. C_LI

neuroscience↗

bioRxiv2020

Pre-stimulus beta-band activity is a signature of statistical learning

Statistical learning (SL) is taken to be the main mechanism by which cognitive systems discover the underlying regularities of the environment. We document, in the context of a classical visual SL task, divergent rhythmic EEG activity during the anticipation of stimuli within patterns versus pattern transitions. Our findings reveal differential pre-stimulus oscillatory activity in the beta band ([~]20 Hz) that indexes learning: it emerges with increased pattern repetitions, and importantly, it is highly correlated with behavioral learning outcomes. These findings hold the promise of converging on an online measure of learning regularities and provide important theoretical insights regarding the mechanisms of SL and prediction. Significance StatementSL has become a major theoretical construct in cognitive science, providing the primary means by which organisms learn about regularities in the environment. As such it is a critical building block for basic and higher-order cognitive functions. Here we identify for the first time a spectral neural index in the time window prior to stimulus presentation, which evolves with increased pattern exposure, and is predictive of learning performance. The manifestation of learning that is revealed not in stimulus processing but in anticipatory moments of the learning episode, makes a direct link between the fields of statistical learning and predictive processing, and suggests a possible mechanistic account of visual SL.

neuroscience↗