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Desdemona Fricker

@desdemonafricker.bsky.social
717 followers 1K following 13 posts

Neuroscientist and Research Director @CNRS. «Orientation&Coordination» team. Head direction, interneurons, memory. Saints-Pères, Paris 👩‍🔬🧠

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Desdemona Fricker @desdemonafricker.bsky.social · 19/09/2026
Memories are dynamic across time! 🧠 Dr. Gisella Vetere kicked off the 2026/27 Saints-Pères Paris Neuroscience Seminar Series with an outstanding talk on Engram Dynamics: from Encoding to Generalization. @sppin-cnrs.bsky.social @upcite.bsky.social #Neuroscience #Memory
Dr Gisella Vetere presenting her work on engrams at the Saints-Pères Neuroscience Seminar Series
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Saints-Pères Paris Institute for the Neurosciences @sppin-cnrs.bsky.social · 11/09/2026
@sppin-cnrs.bsky.social @cnrs.fr is organizing #NeuralNet2026 in Paris on Nov. 25–27 ! Join the 15th annual meeting of GDR NeuralNet @upcite.bsky.social , bringing together researchers working across systems neuroscience, neural data, computational modeling, NeuroAI & data science.
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Jennifer Bussell PhD @jenbussell.bsky.social · 30/07/2026
How does the brain represent the value of knowledge? In our paper--out now at Nature Neuroscience--we identify a representation of intrinsic information value within neural population structures in the orbitofrontal cortex in mice. www.nature.com/articles/s41593-026-02377-y #neuroskyence 🧠🧪 (1/8)
nature.com
Representations of the intrinsic value of information in mouse orbitofrontal cortex - Nature Neuroscience
Mice are motivated to seek information of no extrinsic value. Recording neural activity in orbitofrontal cortex reveals a representation of the value of information that is distinct from the value of ...
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AntonioFR @antferrui.bsky.social · 06/07/2026
Our work on goal-directed theta sweeps is out! We found two different types of theta sweeps in the rat hippocampus. During random foraging, left-right alternating sweeps dominated (Vollan, 25). However, during memory-guided navigation sweeps pointing to hidden goal locations emerged with learning.
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Joao Barbosa @jbarbosa.org · 03/04/2026
Wanna do neuroscience in Paris but can't find interesting lab? Want to come do a sabbatical but don't know who to collaborate? Check this webpage aggregating ~all the neuroscience labs (+200) in Paris. ⚠️only the information of 'verified' profiles is reliable⚠️ Please retweet 🙏 parisneuro.fr
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Juan Facundo Morici @facuumm.bsky.social · 01/04/2026
Thrilled to see our paper published! I’m deeply grateful to the amazing @ggirardeau.bsky.social for trusting me to develop and carry it out. Many thanks as well to @azulsilva.bsky.social , @belalima-paiva.bsky.social and Eleonore for driving this work forward together. www.nature.com/articles/s41...
nature.com
Dorsoventral hippocampus neural assemblies reactivate during sleep following an aversive experience - Nature Neuroscience
Synchronization of sharp-wave ripples across the dorsoventral hippocampus during sleep supports coordinated reactivation that represents negative experiences more faithfully than positive ones.
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Desdemona Fricker @desdemonafricker.bsky.social · 22/03/2026
🧠 Looking forward to Mark Brandon’s visit ! His work on Head Direction coding changed how we think of the neural compass: Network gain maintains a memory trace of previous experience. 🗓️ Join us for his seminar on April 3rd at 11h30 📍45 rue des Saints-Pères, Paris
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Jean Laurens @jeanlaurens.bsky.social · 02/03/2026
Hi BlueSky — I’m bringing over an old SciTwitter thread series exploring how beautifully the vestibular system works from a systems and computational neuroscience perspective. Chapter 1 coming shortly! I’ll keep all chapters threaded below.
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Trends in Neurosciences @cp-trendsneuro.bsky.social · 18/02/2026
'The postsubiculum as a head-direction cortex' by Adrian Duszkiewicz, Desdemona Fricker, Andrea Burgalossi & Adrien Peyrache @adrian-du.bsky.social @desdemonafricker.bsky.social @apeyrache.bsky.social www.cell.com/trends/neuro...
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Adrien Peyrache @apeyrache.bsky.social · 11/02/2026
New paper alert! 🚨 We found that the brain's compass is remarkably stable at two scales 1️⃣ the system maintains its internal organization for weeks 2️⃣ It "remembers" its orientation for weeks, even after a single visit This may be key to how the brain aligns its other maps. Paper: rdcu.be/e3waP
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Saints-Pères Paris Institute for the Neurosciences @sppin-cnrs.bsky.social · 10/02/2026
La @semaineducerveau.bsky.social arrive bientôt au SPPIN ! Nous avons le plaisir d’accueillir une conférence suivie d’une visite du laboratoire par @uligraupner.bsky.social dédié aux approches optogénétiques pour comprendre les circuits neuronaux et le comportement.
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Abraham Zelalem Vollan @azvollan.bsky.social · 28/01/2026
We had a lot of fun doing these experiments! Theta sweeps in MEC and internal direction signals in parasubiculum track moving objects during pursuit and reverse during backward movement. Simultaneously recorded HD cells in other areas remain locked to head direction across behaviors:
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Laetitia Mony @laetitiamony.bsky.social · 28/01/2026
If you are a PhD student or post-doc who wants to learn everything about #electrophysiology or #imaging, consider registering to the Paris Spring school in optical imaging and electrophysiology, that will take place in the center of Paris 11-23 May 2026. Application deadline Feb 2nd parisneuro.ovh
parisneuro.ovh
Paris NeuroCourse | Optical Imaging and Electrophysiological Recording in Neuroscience
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bioRxiv Neuroscience @biorxiv-neursci.bsky.social · 13/01/2026
Active locomotion predictively rescues head direction attractor dynamics in head-fixed mice www.biorxiv.org/content/10.64898/20…
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Mark Brandon @markbrandonlab.bsky.social · 05/01/2026
Fantastic work!
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Mark Brandon @markbrandonlab.bsky.social · 14/01/2026
I’m very happy to share the latest from my lab published in @Nature Hippocampal neurons that initially encode reward shift their tuning over the course of days to precede or predict reward. Full text here: rdcu.be/eY5nh
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Portugues Lab @portugueslab.bsky.social · 07/01/2026
1/6: New publication from the lab: “Plastic landmark anchoring in zebrafish compass neurons” by Ryosuke Tanaka (@ryosuketanaka.bsky.social) and Ruben is available here: rdcu.be/eX1L4
rdcu.be
Plastic landmark anchoring in zebrafish compass neurons
Nature - Using two-photon microscopy with a panoramic virtual reality setup, how head direction cells in larval zebrafish integrate visual landmarks and optic flow to track orientation is revealed.
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Desdemona Fricker @desdemonafricker.bsky.social · 05/01/2026
Coincidence of thalamic HD signal and retrosplenial visual input is detected in the Presubiculum! 🎯 This may be the neuronal basis for landmark anchoring of the HD signal. Pleased to announce the VOR is now available elifesciences.org/articles/92443 Congrats first author Louis Richevaux 🙌
elifesciences.org
Projection-specific integration of convergent thalamic and retrosplenial signals in the presubicular head direction cortex
Nonlinear dendritic integration in single presubicular neurons provides a mechanism for combining vestibular-based head-direction signals and visual landmark signals to anchor the brain’s internal com...
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Portugues Lab @portugueslab.bsky.social · 02/01/2026
1/n: A new collaborative preprint from the lab to start the year: "A multi-ring shifter network computes head direction in zebrafish" together with Siyuan Mei, Martin Stemmler and Andreas Herz from the LMU, Munich.
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Kenneth Harris @kenneth-harris.bsky.social · 14/11/2025
1. New preprint resolving a conundrum in systems neuroscience with an AI scientist, and humans Reilly Tilbury, Dabin Kwon, @haydari.bsky.social, @jacobmratliff.bsky.social, @bio-emergent.bsky.social, @carandinilab.net, @kevinjmiller.bsky.social, @neurokim.bsky.social www.biorxiv.org/content/10.1...
biorxiv.org
Characterizing neuronal population geometry with AI equation discovery
The visual cortex contains millions of neurons, whose combined activity forms a population code representing visual stimuli. There is, however, a discrepancy between our understanding of this code at ...
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Sepiedeh Keshavarzi @sepikeshavarzi.bsky.social · 20/11/2025
📢 We are organising the Senses in Motion conference for the third time, and we are now accepting abstracts for posters or talks. Deadline for abstracts: 19 December Conference dates: 18–21 May 2026 Location: Harnack House, Berlin Register via this page👇 sensesinmotion.org #neuroskyence #neurosky
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Hafting-Fyhn Lab @hafting.bsky.social · 30/10/2025
No GPS in the head? Path integration by entorhinal grid cells without the grid pattern. Interesting paper from Heidelberg. www.nature.com/articles/s41...
nature.com
Grid cells accurately track movement during path integration-based navigation despite switching reference frames - Nature Neuroscience
Grid cells do not maintain a stable pattern during a self-motion-based task, but track animal movement in multiple local reference frames and reanchor to task-relevant objects, thus estimating local r...
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Saikat Ray @ray-neuro.bsky.social · 17/10/2025
Neuroscience projects last several years, and you are usually a bit jaded by the time you wrap it up. Not this one– spending several months on an island in the middle of nowhere, away from all the craziness of the world reminds you how beautiful the world really is. www.youtube.com/watch?v=46sv...
youtube.com
Bat Island: The New Era of Science
YouTube video by Weizmann Institute of Science
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Adrian Duszkiewicz @adrian-du.bsky.social · 15/10/2025
Really excited to share this Opinion piece we've been working on with fellow head-direction cell geeks @apeyrache.bsky.social @desdemonafricker.bsky.social and (bsky-less?) Andrea Burgalossi! While head-direction cells pop up in many cortical regions, we think that one of them is quite unique (1/8)
sciencedirect.com
The postsubiculum as a head-direction cortex
The organisation of thalamocortical networks follows a conserved structure. Traditionally, these are divided into primary sensory systems that receive…
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Adrien Peyrache @apeyrache.bsky.social · 15/10/2025
🚨new paper: the head-direction circuit as a model of primary thalamocortical system. Check this out 👇 kudos to @adrian-du.bsky.social for the huge amount of work put into this opinion piece, starting with the beautiful figures comparing the different thalamocortical systems 🤩
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Desdemona Fricker @desdemonafricker.bsky.social · 28/09/2025
Thanks to the Capitainerie de l’Isle and to Nathalie for hosting our exhibit ✨
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Lea Duncker @leaduncker.bsky.social · 03/10/2025
Travel awards are available for undergraduate students looking to attend #Cosyne25! The application is short, and the deadline is Nov 12. @cosynemeeting.bsky.social Application: shorturl.at/6NEyk More info: www.cosyne.org/travel-grants (1/2)
cosyne.org
Travel Grants — COSYNE
Apply for COSYNE 2026 Travel Grants to support your participation in Lisbon and Cascais, Portugal. Grants are available for students, postdocs, and PIs, including programs for Childcare, Presenters, N...
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Saints-Pères Paris Institute for the Neurosciences @sppin-cnrs.bsky.social · 03/09/2025
Dear #ParisNeuroscience community, here is the schedule of the upcoming 'Neural Networking Night' season !
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Carlos Brody @carlosbrody.bsky.social · 19/09/2025
2/6 Recording in decision-making regions from many neurons at once revealed the neurons' collective evolution as decisions were made Each decision had two phases: first, neural state was sensitive to sensory inputs; then, trajectories in neural state space turned and became insensitive to inputs.
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Thomas Luo @thomas-zhihao-luo.bsky.social · 17/09/2025
How does the brain decide? 🧠 Our new @nature.com paper shows that neural activity switches from an 'evidence gathering' to a 'commitment' state at a precise moment we call nTc. After nTc, new evidence is ignored, revealing a neural marker for the instant when the mind is made up. rdcu.be/eGUrv
nature.com
Transitions in dynamical regime and neural mode during perceptual decisions - Nature
Simultaneous recordings were made of hundreds of neurons in the rat frontal cortex and striatum, showing that decision commitment involves a rapid, coordinated transition in dynamical regime and neura...
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Adrien Peyrache @apeyrache.bsky.social · 16/09/2025
🚨New preprint alert! The thalamus has long been seen as a relay of sensory signals to cortex. But could it also generate its own structured activity? Our study explores this question in the head-direction (HD) system. Some explanation 🧵👇 1/13 www.biorxiv.org/content/10.1...
biorxiv.org
Coherent dynamics of thalamic head-direction neurons irrespective of input
While the thalamus is known to relay and modulate sensory signals to the cortex, whether it also participates in active computation and intrinsic signal generation remains unresolved. The anterodorsal...
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Desdemona Fricker @desdemonafricker.bsky.social · 24/07/2025
Voir Montrer Regarder 👀 Observer Mesurer Vérifier #SciArt If you are in Paris in September check out our exhibit “Regards Croisés”: Come for the Art, stay for the Science ! This scientific outreach event is supported by @c-brains.bsky.social, @sppin-cnrs.bsky.social and the Capitainerie de l’Isle.
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Tim Viney @vineytj.bsky.social · 15/09/2025
*New preprint from the lab* – “Granularity of thalamic head direction cells” doi.org/10.1101/2025... 🧠📈 🧪 1/11
doi.org
Granularity of thalamic head direction cells
Head direction signaling is fundamental for spatial orientation and navigation. The anterodorsal nucleus of the thalamus (ADn) contains a high density of head direction (HD) cells that process sensori...
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Jerome Epsztein @jeromeepsztein.bsky.social · 11/09/2025
Happy to share our new paper with Mathilde Nordlund and Julie Koenig out @currentbiology.bsky.social. We used virtual reality in mice to study hippocampal distance coding. Our results suggest a primary contribution of grid cells to distance over cue-dependent place cell coding. shorturl.at/63yFo
Color-coded mean firing rate maps of place fields detected in the forth trials (left, sorted by the location of place fields peak) and back trials (right, sorted according to firing order in the forth trials) of all bidirectional cells recorded in the track with objects (top) or without objects (bottom). The color represents the intensity of the mean firing rate in a given bin normalized to the maximum mean firing rate (peak rate) in each direction. Note that in the CP condition, the mean firing map in one direction is the mirror image of the mean firing map in the other direction, indicating strong distance coding.
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Emilie Macé @mace-lab.bsky.social · 11/09/2025
Thrilled to share that our work is now published in Science! ✨ We found a preference for visual objects in the mouse spatial navigation system where they dynamically refine head-direction coding. In short, objects boost our inner compass! 🧭 www.science.org/doi/10.1126/... 🧵1/
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Mick Craig @mickcraig.bsky.social · 04/09/2025
And the Valero / Buzsaki paper: www.science.org/doi/10.1126/...
science.org
Cooperative actions of interneuron families support the hippocampal spatial code
Identifying the computational roles of different neuron families is crucial for understanding neural networks. Most neural diversity is embodied in various types of γ-aminobutyric acid–mediated (GABAe...
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International Brain Laboratory @intlbrainlab.bsky.social · 03/09/2025
Two flagship papers from the International Brain Laboratory, now out in ‪@Nature.com‬: 🧠 Brain-wide map of neural activity during complex behaviour: doi.org/10.1038/s41586-025-09235-0 🧠 Brain-wide representations of prior information in mouse decision-making: doi.org/10.1038/s41586-025-09226-1 +
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Cantin Ortiz @cantinortiz.bsky.social · 01/07/2025
The main project from my PhD, in collaboration with Manuela Allegra and @schlab.bsky.social is now available as a preprint! We wondered how the hippocampus and the visual cortex may differ in the way they refine sensory inputs into internal representations
biorxiv.org
Task engagement differentially drives hippocampal and neocortical neural codes
Sensory inputs are progressively transformed into internal representations of the environment along the cortical hierarchy. How does the behavioral relevance of these inputs affect this encoding? Usin...
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Saints-Pères Paris Institute for the Neurosciences @sppin-cnrs.bsky.social · 23/07/2025
🎨🔬 Quand l’art rencontre la science ! Le SPPIN est heureux de vous annoncer l'Expo #SciArt “Regards Croisés” avec l’artiste Sophie Sainte-Marie-Heim et notre collègue @desdemonafricker.bsky.social 🗓 22–28 sept. 2025 📍 Capitainerie de l’Isle, 26 rue Chanoinesse, Paris 4e Venez nombreux !
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Laura Dugué @lauradugue.bsky.social · 21/07/2025
🚨PhD student position in #cognitive_psychology and #neuroscience, on a project directed by André Knops and in collaboration with the Dugué Lab! @upcite.bsky.social | @cnrs.fr Funded by the @agencerecherche.bsky.social (Agence nationale de la recherche) www.linkedin.com/jobs/view/42...
linkedin.com
Université Paris Cité hiring Doctoral Student in Paris, Île-de-France, France | LinkedIn
Posted 1:38:05 PM. PhD Student Position at University Paris CitéIn the context of a collaborative project involving…See this and similar jobs on LinkedIn.
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Abhilasha Joshi, PhD @rhythmicspikes.bsky.social · 01/08/2025
📣 We are expanding! Repost 🙏🏽 - Postdoc (funded by @simonsfoundation.org grant on synchronisation between cognitive representations and stepping) - Project Associates - Create your role! (Reach out if you are keen on these topics and these roles do not define you 👀🤗) www.neuroact.in
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Kevin Mitchell @wiringthebrain.bsky.social · 24/07/2025
Remote activation of place codes by gaze in a highly visual animal www.nature.com/articles/s41... - very cool study with chickadees!
nature.com
Remote activation of place codes by gaze in a highly visual animal - Nature
Place cells in the chickadee hippocampus coherently represent locations in space, whether physically visited or viewed, enabling spatial reasoning at a distance through a unified process coordinated b...
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Desdemona Fricker @desdemonafricker.bsky.social · 24/07/2025
Voir Montrer Regarder 👀 Observer Mesurer Vérifier #SciArt If you are in Paris in September check out our exhibit “Regards Croisés”: Come for the Art, stay for the Science ! This scientific outreach event is supported by @c-brains.bsky.social, @sppin-cnrs.bsky.social and the Capitainerie de l’Isle.
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Blake Richards @tyrellturing.bsky.social · 11/07/2025
1/3) This may be a very important paper, it suggests that there are no prediction error encoding neurons in sensory areas of cortex: www.biorxiv.org/content/10.1... I personally am a big fan of the idea that cortical regions (allo and neo) are doing sequence prediction. But... 🧠📈 🧪
biorxiv.org
Sensory responses of visual cortical neurons are not prediction errors
Predictive coding is theorized to be a ubiquitous cortical process to explain sensory responses. It asserts that the brain continuously predicts sensory information and imposes those predictions on lo...
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Vikaas Sohal @vikaassohal.bsky.social · 30/06/2025
New work! Learning is assumed to involve synaptic plasticity, but which specific synapses change to enable higher order cognitive functions? We actually find that cognitive flexibility involves potentiation of long-range GABAergic synapses from prefrontal PV neurons: www.biorxiv.org/content/10.1...
biorxiv.org
Synaptic plasticity of prefrontal long-range inhibition regulates cognitive flexibility
While glutamatergic synaptic plasticity is believed to be a fundamental mechanism mediating learning, the behavioral significance of plasticity at cortical GABAergic synapses remains less well underst...
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Saints-Pères Paris Institute for the Neurosciences @sppin-cnrs.bsky.social · 11/07/2025
Great wave of @agencerecherche.bsky.social results for SPPIN ! Congrats to our researchers & their amazing partners! @desdemonafricker.bsky.social : HDNavigGO @npanayotis.bsky.social : ReGeNeRETT G. Caron: MNIONALS (JCJC) @brandonstell.bsky.social : AdaptingMovement @cnrs.fr @upcite.bsky.social
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Angelo Forli @aforli89.bsky.social · 09/07/2025
Our study is out in Nature! Using wireless Neuropixels we recorded hippocampal activity in freely flying bats and uncovered replay and theta(less) sweeps, revealing striking differences from classic rodent models. 👉 www.nature.com/articles/s41...
nature.com
Replay and representation dynamics in the hippocampus of freely flying bats - Nature
Nature - Replay and representation dynamics in the hippocampus of freely flying bats
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Ben Kanter @beneuroscience.bsky.social · 26/06/2025
Our new paper out now in Science explores how neural activity in the lateral entorhinal cortex (LEC) *drifts* over time - and *jumps* at key boundaries - to help organize events in memory. 🔗 www.science.org/doi/10.1126/... Here's a quick summary of what we found 🧵👇
science.org
Event structure sculpts neural population dynamics in the lateral entorhinal cortex
Our experience of the world is a continuous stream of events that must be segmented and organized at multiple timescales. The neural mechanisms underlying this process remain unknown. In this work, we...
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Edvard I Moser @edvardmoser.bsky.social · 26/06/2025
Your brain doesn’t just passively track time ⏳ - it structures it. In @Science.org we show that activity in 🧠 memory circuits (LEC) drifts constantly, but makes sharp jumps at key moments, segmenting life into meaningful events. (1/2) 👉 www.science.org/doi/10.1126/...
science.org
Event structure sculpts neural population dynamics in the lateral entorhinal cortex
Our experience of the world is a continuous stream of events that must be segmented and organized at multiple timescales. The neural mechanisms underlying this process remain unknown. In this work, we...
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Janelia Research Campus @hhmijanelia.bsky.social · 23/06/2025
🚶Aimlessly wandering around a city or exploring the new mall may seem unproductive, but new research led by @zh0ng0.bsky.social @marius10p.bsky.social @computingnature.bsky.social suggests it could play an important role in how our brains learn.‬‬ 🧠 🔗 www.janelia.org/news/zoning-...
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