PhD student in the Moser lab. Spatial cognition, grid cells, population dynamics, high-density ephys. MD from 🇳🇴
Abraham Zelalem Vollan
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Story time friends...
Ring attractor networks rely on fine-tuned symmetric connectivity.
The fly head direction network has ring attractor dynamics but heterogeneous connectivity.
How is this possible? 1/🧵
Link: www.biorxiv.org/content/10.6...
Very excited to announce the first preprint from the lab @ucsantabarbara.bsky.social -- "Predictive pursuit emerges in high-dimensional RNNs." @wtredman.bsky.social (starting his own group at JHU this fall) summarizes the work nicely in this thread.
Brilliant work on the development of grid cells by Matteo et al!
My first first-author paper is on bioRxiv! Here we ask whether the same subset of neurons in ACC always display object correlates during extensive familiarisation to 2 objects. A short 🧵1/10
Last week, we finally submitted my first paper during my PhD (bioRXiv: www.biorxiv.org/content/10.6...). The paper is about change-of-mind (COM) behavior.
You know when you're taking a test and switch your answer after second-guessing yourself? We studied what happens in the brain at that moment.
It has been super fun to work on this, where we learned that:
1) Mouse PFC is needed for model-based override of habits.
2) Separate PFC populations encode a 'policy' and the current 'value'.
3) The policy and value codes alternate theta sweeps towards the goal.
...and much much more!
1/N: Dear cognitive map fans, I’d like to share a model I’ve been working on for a while (clearing backlog :). I show how a vector navigation architecture (VNA) and a “positional inference network” (PIN) can build Universal Cognitive Maps (UCMs) for abstract spaces.
www.biorxiv.org/content/10.6...
1/6
Do neighboring #PlaceCells in #Hippocampus CA1 map neighboring locations in space? 🧠🗺️
Is there micro-scale spatial topography in the hippocampus?
See our latest paper from @kavlintnu now out in @pnas.org www.pnas.org/doi/10.1073/...
Video
Fantastic opportunity to do pioneering single-unit recordings from the HUMAN hippocampus and other parts of the brain, with @jorgen-sugar.bsky.social at @uio.no, Norway.
Brad Hulse
andy alexander
Abraham Zelalem Vollan
My main postdoc work is now published: www.nature.com/articles/s41...! We (myself, Isabel Low, Frances Cho, and @lgiocomo.bsky.social) discovered task-relevant remote representations in entorhinal cortex independent of CA1. #paperthread below! 1/13
www.biorxiv.org
Lucie Descamps
New preprint out 🚨 “Predictive pursuit emerges in high-dimensional recurrent neural networks”! This was an awesome collaboration with co-first author @fatihdinc.bsky.social , @andyalexander.bsky.social, @xiaoxiao-lin.bsky.social, and May Chen biorxiv.org/content/10.6... 1/
shijiegu
Neurons in medial entorhinal cortex collectively represent discrete nonlocal positions during immobility. During this nonlocal coding, CA1 is uncoupled from entorhinal cortex. These representations ar...
How do brains plan actions towards goals?
To get at this question we studied mice navigating complex mazes as goals changed on every trial 🧵
Work with @thomasakam.bsky.social @behrenstimb.bsky.social @kristorpjensen.bsky.social now on BioRxiv: www.biorxiv.org/content/10.6...
Video
1/7 🧠 My journey into development begins with this work and question: how does the brain's spatial navigation system develop? We found that the neural networks for spatial navigation (tori and rings) are preconfigured and only later anchor gradually to the world with experience! 🧵
Topography is a well-described and well-known concept for cortical organization in
primary sensory and motor cortices of mammalian brains. Similar ...
We have PhD positions and Post Doc positions available! www.med.uio.no/imb/english/... Please apply if you are interested in human invasive intracranial recordings or applied machine learning in a neuroscientific context.
Deadlines 1st of March (Sunday!) and 4th of March.
Please RT!
Video
Heterogeneous single-cell dynamics support stable population codes for objects in the mouse anterior cingulate cortex https://www.biorxiv.org/content/10.64898/2026.02.06.704307v1
Matteo Guardamagna
Jørgen Sugar
A half-century old question may have its final answer. Using high-resolution #Mini2P microscopes, we find no evidence of local topography in #PlaceCells. Place fields of neighbouring cells are no more similar than those of randomly selected cells. 🧠🗺️ Out now in @pnas.org www.pnas.org/doi/10.1073/...
Topography is a well-described and well-known concept for cortical organization in
primary sensory and motor cortices of mammalian brains. Similar ...
