Simon Faghel-Soubeyrand

@simonfsoubeyrand.bsky.social

Oxford Postodoctoral Researcher, Staresina Lab || Banting Postdoctoral Fellow || vision, memory, sleep, machine learning

🔔 Preprint: “Hippocampal ripples evoke a stereotyped cortical response followed by spindle-mediated network synchronization.” Combining iEEG+scalp EEG during sleep, we show that hippocampal ripples leave a decodable cortical fingerprint and are followed by brain-wide spindle synchronization!

doi.org

🚨 New Preprint 🚨 I’m excited to share the first paper from my postdoc. We found age differences in the timescales of neural activity in the hippocampus during movie viewing 👀 These timescales were related to memory specificity in an interesting way (spoiler: the hippocampus may not be special!?)

bioRxiv Neuroscience@biorxiv-neursci.bsky.social · 3mo ago

Age Differences in Hippocampal Neural Timescales During Movie-Viewing https://www.biorxiv.org/content/10.64898/2026.05.05.723065v1

How do memories guide behaviour? Multiple memory representations, from detailed to gist-like, let us flexibly reconstruct or reproduce past experiences to behave adaptively across species. Now out in Physiological Reviews with Morris Moscovitch, Melanie Sekeres & @brianlevine.bsky.social!

Adaptive episodic memory: how multiple memory representations drive behavior in humans and nonhumans | Physiological Reviews | American Physiological Society

Episodic memory is a declarative long-term memory of a specific past experience. As such, it is multifaceted, encompassing both the objective and subjective components of that experience. These components can be flexibly represented at different levels of granularity, from precise, context-specific details to generalized, gistlike representations. In this review, we suggest that 1) multiple representations of an episodic memory at different levels of granularity are simultaneously encoded into a memory trace and 2) the relative weighting of these representations determines the extent to which a memory is reconstructed or reproduced at retrieval. We propose that this representational flexibility drives adaptive behavior by prioritizing reconstruction or reproduction depending on the age of the memory, its relationship to prior knowledge, current attentional goals or task demands, and individual differences. Drawing on research in humans and nonhuman animals, we show a close correspondence between psychological and neural representations of a memory across encoding, consolidation, and retrieval. Specifically, we discuss how hippocampal activity in humans and engram formation and activation in rodents support the reproduction of detailed memory representations, whereas schema formation across species, mediated by the medial prefrontal cortex, facilitates reconstruction and generalization to guide behavior. Finally, we consider how species- and individual-level differences shape episodic memory representations. By integrating findings across species, we illustrate how the correspondence between neural and psychological representations enables multiple memory representations to balance stability and flexibility, ultimately driving adaptive behavior.

journals.physiology.org

1/7 Can infants recognise the world around them? 👶🧠 As part of the FOUNDCOG project, we scanned 134 awake infants using fMRI. Published today in Nature Neuroscience, our research reveals 2-month-old infants already possess complex visual representations in VVC that align with DNNs.

How does the brain replay memories during sleep? Excited to share our new preprint, the outcome of an extensive effort led by Johannes Niediek, showing that reactivation of human concept neurons reflects memory content rather than event sequence.

bioRxiv Neuroscience@biorxiv-neursci.bsky.social · 7mo ago

Episodic memory consolidation by reactivation of human concept neurons during sleep reflects contents, not sequence of events https://www.biorxiv.org/content/10.64898/2026.01.10.698827v1

What if we could tell you how well you’ll remember your next visit to your local coffee shop? ☕️ In our new Nature Human Behaviour paper, we show that the 𝗾𝘂𝗮𝗹𝗶𝘁𝘆 𝗼𝗳 𝗮 𝘀𝗽𝗮𝘁𝗶𝗮𝗹 𝗿𝗲𝗽𝗿𝗲𝘀𝗲𝗻𝘁𝗮𝘁𝗶𝗼𝗻 can be measured with neuroimaging – and 𝘁𝗵𝗮𝘁 𝘀𝗰𝗼𝗿𝗲 𝗽𝗿𝗲𝗱𝗶𝗰𝘁𝘀 𝗵𝗼𝘄 𝘄𝗲𝗹𝗹 𝗻𝗲𝘄 𝗲𝘅𝗽𝗲𝗿𝗶𝗲𝗻𝗰𝗲𝘀 𝘄𝗶𝗹𝗹 𝘀𝘁𝗶𝗰𝗸.

Nature Human Behaviour@nathumbehav.nature.com · 7mo ago

New study by @xrmasiso.bsky.social et al shows that spatial contexts with more reliable brain representations better support memory for future experiences within them, revealing how stable neural maps help the brain organize and recall life events.

Thrilled that my recent paper, Hippocampal Ripples during Offline Periods Predict Human Motor Sequence Learning, was selected for the “This Week in The Journal” highlight! 🤩 Huge thanks to @bstaresina.bsky.social and our collaborators who made this work possible! doi.org/10.1523/JNEU... #JNeurosci

Hippocampal Ripples during Offline Periods Predict Human Motor Sequence Learning

High-frequency bursts in the hippocampus, known as ripples (80–120 Hz in humans), have been shown to support episodic memory processes. However, converging recent evidence in rodent models and human n...

jneurosci.org

SfN Journals@sfnjournals.bsky.social · 9mo ago

This Week in The Journal #JNeurosci | How Partial Occlusion Influences Visual Processing; Hippocampal Ripples during Rest May Promote Motor Learning vist.ly/4f8bg

What aspects of human knowledge do vision models like CLIP fail to capture, and how can we improve them? We suggest models miss key global organization; aligning them makes them more robust. Check out LukasMuttenthaler's work, finally out (in Nature!?) www.nature.com/articles/s41... + our blog! 1/3

Aligning machine and human visual representations across abstraction levels - Nature

Aligning foundation models with human judgments enables them to more accurately approximate human behaviour and uncertainty across various levels of visual abstraction, while additionally improving th...

nature.com

Super excited to share a new preprint! We asked a simple-but-big question: What changes in the brain when someone becomes an expert? Using chess ♟️ + fMRI 🧠 + representational geometry & dimensionality 📈, we ask: 1️⃣ WHAT information is encoded? 2️⃣ HOW is it structured? 3️⃣ WHERE is it expressed? 1/n

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Our "mind captioning" paper is now published in Science Advances @science.org . The method generates descriptive text of what we perceive and recall from brain activity — a linguistic interpretation of nonverbal mental content rather than language decoding. doi.org/10.1126/scia...

Mind captioning: Evolving descriptive text of mental content from human brain activity

Nonverbal thoughts can be translated into verbal descriptions by aligning semantic representations between text and the brain.

doi.org

Introducing CorText: a framework that fuses brain data directly into a large language model, allowing for interactive neural readout using natural language. tl;dr: you can now chat with a brain scan 🧠💬 1/n

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🚨Preprint: Semantic Tuning of Single Neurons in the Human Medial Temporal Lobe 1/8: How do human neurons encode meaning? In this work, led by Katharina Karkowski, we recorded hundreds of human MTL neurons to study semantic coding in the human brain: doi.org/10.1101/2025...

Semantic Tuning of Single Neurons in the Human Medial Temporal Lobe

The Medial Temporal Lobe (MTL) is key to human cognition, supporting memory, emotional processing, navigation, and semantic coding. Rare direct human MTL recordings revealed concept cells, which were ...

doi.org