Decoding the rhythmic representation and communication of visual contents

Trends in Neurosciences, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Language: Английский

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Distinct neural signatures underlying information maintenance and manipulation in working memory

Cerebral Cortex, Journal Year: 2024, Volume and Issue: 34(3)

Published: March 1, 2024

Abstract Previous working memory research has demonstrated robust stimulus representations during maintenance in both voltage and alpha-band activity electroencephalography. However, the exact functions of these 2 neural signatures have remained controversial. Here we systematically investigated their respective contributions to manipulation. Human participants either maintained a previously seen spatial location, or manipulated location following mental rotation cue over delay. Using multivariate decoding, observed low-frequency oscillatory with distinct spatiotemporal dynamics: were most evident posterior channels activity, but prominent more anterior, central signals. Moreover, temporal emergence representation preceded that suggesting might carry stimulus-specific source signals originated internally from anterior cortex, whereas reflect feedback cortex received higher-order cortex. Lastly, while coded low-dimensional subspace, was higher-dimensional underwent representational transformation exclusively predicted behavior. Together, results highlight crucial role memory, support functional distinctions between activity.

Language: Английский

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Representations of imaginary scenes and their properties in cortical alpha activity

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: June 4, 2024

Abstract Imagining natural scenes enables us to engage with a myriad of simulated environments. How do our brains generate such complex mental images? Recent research suggests that cortical alpha activity carries information about individual objects during visual imagery. However, it remains unclear if more imagined contents as are similarly represented in activity. Here, we answer this question by decoding the from rhythmic patterns. In an EEG experiment, participants based on detailed written descriptions, which conveyed four complementary scene properties: openness, naturalness, clutter level and brightness. By conducting classification analyses power patterns across neural frequencies, were able decode both well their properties band, showing also images rhythms. A cross-classification analysis between imagery task perception task, presented described scenes, showed representations band partly shared late stages perception. This mediates top-down re-activation scene-related

Language: Английский

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Representational shifts from feedforward to feedback rhythms index phenomenological integration in naturalistic vision

Communications Biology, Journal Year: 2025, Volume and Issue: 8(1)

Published: April 14, 2025

How does the brain integrate complex and dynamic visual inputs into phenomenologically seamless percepts? Previous results demonstrate that when are organized coherently across space time, they more strongly encoded in feedback-related alpha rhythms, less feedforward-related gamma rhythms. Here, we tested whether this representational shift from feedforward to feedback rhythms is linked phenomenological experience of coherence. In an Electroencephalography (EEG) study, manipulated degree spatiotemporal coherence by presenting two segments same video hemifields, either synchronously or asynchronously (with a delay between segments). We asked participants perceived stimulus as coherent incoherent. When stimuli were presented at perceptual threshold (i.e., was judged 50% times), perception co-varied with coding rhythms: coherent, represented activity; incoherent, activity. Whether input incoherent thus depends on shifts

Language: Английский

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Neural oscillations and top-down connectivity are modulated by object-scene congruency

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: April 20, 2025

Abstract The knowledge we have about how the world is structured known to influence object recognition. One way this demonstrated through a congruency effect, where recognition faster and more accurate if items are presented in expected scene contexts. However, our understanding of dynamic neural mechanisms that underlie effects under-explored. Using MEG, examine between an prior results changes oscillatory activity brain, which regions underpin whether arise from top-down or bottom-up modulations connectivity. We observed information impacts processing visual objects behaviour, Processing were incongruent with resulted slower reaction times, increased low frequency ventral pathway, connectivity anterior temporal lobe posterior cortex. Our reveal recurrent dynamics within pathway modulated by imbued surrounding environment, suggesting recognise fundamentally linked their context.

Language: Английский

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Comparison of whole-brain task-modulated functional connectivity methods for fMRI task connectomics

Communications Biology, Journal Year: 2024, Volume and Issue: 7(1)

Published: Oct. 26, 2024

Language: Английский

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Enhanced and idiosyncratic neural representations of personally typical scenes

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2025, Volume and Issue: 292(2043)

Published: March 1, 2025

Previous research shows that the typicality of visual scenes (i.e. if they are good examples a category) determines how easily can be perceived and represented in brain. However, unique diets individuals exposed to across their lifetimes should sculpt very personal notions typicality. Here, we thus investigated whether more typical individual observers accurately We used drawings enable participants describe (e.g. kitchen) converted these into three-dimensional renders. These renders were as stimuli scene categorization task, during which recorded electroencephalography (EEG). In line with previous findings, was most accurate for resembling participants. Our EEG analyses reveal two critical insights on differences emerge neural level. First, personally yielded enhanced representations from around 200 ms after onset. Second, idiosyncratic ways, reduced dependence high-level features. interpret findings predictive processing framework, where internal models categories formed through experience shape analysis ways.

Language: Английский

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Mapping the dynamics of visual feature coding: Insights into perception and integration

PLoS Computational Biology, Journal Year: 2024, Volume and Issue: 20(1), P. e1011760 - e1011760

Published: Jan. 8, 2024

The basic computations performed in the human early visual cortex are foundation for perception. While we know a lot about these computations, key missing piece is how coding of features relates to our perception environment. To investigate feature coding, interactions, and their relationship perception, investigated neural responses perceptual similarity judgements large set stimuli that varied parametrically along four dimensions. We measured using electroencephalography (N = 16) 256 grating orientation, spatial frequency, contrast, colour. then mapped response profiles each related independently obtained behavioural stimulus similarity. results confirmed fundamental principles system, such all were processed simultaneously but differed dynamics, there was distinctive conjunction different combinations responses. Importantly, modelling behaviour revealed every contributed judgements, despite untargeted nature task. Further, between evident from initial processing stages, signifying features, not just contribute This study highlights importance understanding progresses through hierarchy stages

Language: Английский

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Coherent categorical information triggers integration-related alpha dynamics

Journal of Neurophysiology, Journal Year: 2024, Volume and Issue: 131(4), P. 619 - 625

Published: Feb. 28, 2024

Our brain integrates dynamic inputs across the visual field to create coherent experiences. Such integration processes have previously been linked cortical alpha dynamics. In this study, integration-related activity was observed not only when snippets from same video were presented, but also different basic-level category highlighting flexibility of neural processes.

Language: Английский

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Integrative processing in artificial and biological vision predicts the perceived beauty of natural images

Science Advances, Journal Year: 2024, Volume and Issue: 10(9)

Published: March 1, 2024

Previous research shows that the beauty of natural images is already determined during perceptual analysis. However, it unclear which computations give rise to perception beauty. Here, we tested whether perceived predicted by spatial integration across an image, a computation reduces processing demands aggregating image parts into more efficient representations whole. We quantified integrative in artificial deep neural network model, where degree was amount deviation between activations for whole and its constituent parts. This quantification ratings four studies with different stimuli designs. In complementary functional magnetic resonance imaging study, show human visual cortex similarly predicts Together, our results establish as computational principle facilitates analysis thereby mediates

Language: Английский

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