Michael Tildahl
@tildahl.bsky.social
Reposted by Michael Tildahl
"Spiking Networks Hate It! Find Out the One Plasticity Trick They Don’t Want You to Know! Never stabilise models by hand again." - I woke up thinking we missed an opportunity with the title of this one. :/ www.science.org/doi/10.1126/... Also: It snowed in Vienna, 10cm white fluffies! Happy Sunday!
Inhibitory Plasticity Balances Excitation and Inhibition in Sensory Pathways and Memory Networks
Plasticity at inhibitory synapses maintains balanced excitatory and inhibitory synaptic inputs at cortical neurons.
www.science.org
November 23, 2025 at 7:09 AM
"Spiking Networks Hate It! Find Out the One Plasticity Trick They Don’t Want You to Know! Never stabilise models by hand again." - I woke up thinking we missed an opportunity with the title of this one. :/ www.science.org/doi/10.1126/... Also: It snowed in Vienna, 10cm white fluffies! Happy Sunday!
Reposted by Michael Tildahl
🚨New Preprint!
How can we model natural scene representations in visual cortex? A solution is in active vision: predict the features of the next glimpse! arxiv.org/abs/2511.12715
+ @adriendoerig.bsky.social , @alexanderkroner.bsky.social , @carmenamme.bsky.social , @timkietzmann.bsky.social
🧵 1/14
How can we model natural scene representations in visual cortex? A solution is in active vision: predict the features of the next glimpse! arxiv.org/abs/2511.12715
+ @adriendoerig.bsky.social , @alexanderkroner.bsky.social , @carmenamme.bsky.social , @timkietzmann.bsky.social
🧵 1/14
Predicting upcoming visual features during eye movements yields scene representations aligned with human visual cortex
Scenes are complex, yet structured collections of parts, including objects and surfaces, that exhibit spatial and semantic relations to one another. An effective visual system therefore needs unified ...
arxiv.org
November 18, 2025 at 12:37 PM
🚨New Preprint!
How can we model natural scene representations in visual cortex? A solution is in active vision: predict the features of the next glimpse! arxiv.org/abs/2511.12715
+ @adriendoerig.bsky.social , @alexanderkroner.bsky.social , @carmenamme.bsky.social , @timkietzmann.bsky.social
🧵 1/14
How can we model natural scene representations in visual cortex? A solution is in active vision: predict the features of the next glimpse! arxiv.org/abs/2511.12715
+ @adriendoerig.bsky.social , @alexanderkroner.bsky.social , @carmenamme.bsky.social , @timkietzmann.bsky.social
🧵 1/14
Reposted by Michael Tildahl
Kazuki Irie has a forthcoming paper in NeurIPS that studies the following idea:
Linear attention has cheap, unbounded memory but low precision, whereas softmax attention has expensive, bounded memory but high precision. These can be combined to build better transformers.
arxiv.org/abs/2506.00744
Linear attention has cheap, unbounded memory but low precision, whereas softmax attention has expensive, bounded memory but high precision. These can be combined to build better transformers.
arxiv.org/abs/2506.00744
Blending Complementary Memory Systems in Hybrid Quadratic-Linear Transformers
We develop hybrid memory architectures for general-purpose sequence processing neural networks, that combine key-value memory using softmax attention (KV-memory) with fast weight memory through dynami...
arxiv.org
November 4, 2025 at 10:33 AM
Kazuki Irie has a forthcoming paper in NeurIPS that studies the following idea:
Linear attention has cheap, unbounded memory but low precision, whereas softmax attention has expensive, bounded memory but high precision. These can be combined to build better transformers.
arxiv.org/abs/2506.00744
Linear attention has cheap, unbounded memory but low precision, whereas softmax attention has expensive, bounded memory but high precision. These can be combined to build better transformers.
arxiv.org/abs/2506.00744
Reposted by Michael Tildahl
How does the brain find its way in realistic environments? 🧠 Using deep RL and neural data, we show that hippocampal-like networks support navigation, learning, and generalisation in partially observable environments—mirroring real animal behaviour. Now out:
www.nature.com/articles/s41...
#neuroAI
www.nature.com/articles/s41...
#neuroAI
Hippocampus supports multi-task reinforcement learning under partial observability - Nature Communications
Neural mechanisms underlying reinforcement learning in naturalistic environments are not fully understood. Here authors show that reinforcement learning (RL) agents with hippocampal-like recurrence, u...
www.nature.com
November 3, 2025 at 10:20 AM
How does the brain find its way in realistic environments? 🧠 Using deep RL and neural data, we show that hippocampal-like networks support navigation, learning, and generalisation in partially observable environments—mirroring real animal behaviour. Now out:
www.nature.com/articles/s41...
#neuroAI
www.nature.com/articles/s41...
#neuroAI
Reposted by Michael Tildahl
Reposted by Michael Tildahl
🚨Pre-print alert! 🚨https://www.biorxiv.org/content/10.1101/2025.10.17.683171v1
Our new study tackles the question: do all neurons in motor cortices (MC) encode movement & coordinate as we move? Answering this question will be key for effectively targeting motor representations in BCIs.
Our new study tackles the question: do all neurons in motor cortices (MC) encode movement & coordinate as we move? Answering this question will be key for effectively targeting motor representations in BCIs.
The spatiotemporal structure of neural activity in motor cortex during reaching
Intracortical brain-computer interfaces (BCI) leverage knowledge about neural representations to translate movement-related neural activity into actions. BCI implants have targeted broad cortical regi...
www.biorxiv.org
October 20, 2025 at 6:54 PM
🚨Pre-print alert! 🚨https://www.biorxiv.org/content/10.1101/2025.10.17.683171v1
Our new study tackles the question: do all neurons in motor cortices (MC) encode movement & coordinate as we move? Answering this question will be key for effectively targeting motor representations in BCIs.
Our new study tackles the question: do all neurons in motor cortices (MC) encode movement & coordinate as we move? Answering this question will be key for effectively targeting motor representations in BCIs.
Reposted by Michael Tildahl
Really interesting work by Bakhurin and colleagues challenging the reward prediction error hypothesis of dopamine:
www.nature.com/articles/s41...
I love this figure which both echoes and undermines the famous figure from Schultz et al. (1997).
www.nature.com/articles/s41...
I love this figure which both echoes and undermines the famous figure from Schultz et al. (1997).
October 14, 2025 at 11:05 AM
Really interesting work by Bakhurin and colleagues challenging the reward prediction error hypothesis of dopamine:
www.nature.com/articles/s41...
I love this figure which both echoes and undermines the famous figure from Schultz et al. (1997).
www.nature.com/articles/s41...
I love this figure which both echoes and undermines the famous figure from Schultz et al. (1997).
Reposted by Michael Tildahl
🧠🚨 How does the hippocampus transform the visual similarity space to resolve memory interference?
In this new preprint, we found that the hippocampus sequentially inverts the behaviorally relevant dimensions of similarity 🧵
www.biorxiv.org/content/10.1...
In this new preprint, we found that the hippocampus sequentially inverts the behaviorally relevant dimensions of similarity 🧵
www.biorxiv.org/content/10.1...
Hippocampal transformations occur along dimensions of memory interference
The role of the hippocampus in resolving memory interference has been greatly elucidated by considering the relationship between the similarity of visual stimuli (input) and corresponding similarity o...
www.biorxiv.org
October 14, 2025 at 4:48 PM
🧠🚨 How does the hippocampus transform the visual similarity space to resolve memory interference?
In this new preprint, we found that the hippocampus sequentially inverts the behaviorally relevant dimensions of similarity 🧵
www.biorxiv.org/content/10.1...
In this new preprint, we found that the hippocampus sequentially inverts the behaviorally relevant dimensions of similarity 🧵
www.biorxiv.org/content/10.1...
Reposted by Michael Tildahl
Which one should I do next? The big Swedish study that RFK & his buddies pretend doesn’t exist? Or one of the other 2 studies he mentioned at the press conference?
Vote by commenting!
Vote by commenting!
If you’ve been following the RFK Jr autism news, then you’ve probably heard that there’s a systematic review “proving” Tylenol causes autism.
Here’s my review of that paper👇🏼
open.substack.com/pub/epiellie...
Here’s my review of that paper👇🏼
open.substack.com/pub/epiellie...
The best evidence Tylenol causes autism isn't great
On Monday, RFK Jr announced Tylenol ‘causes’ autism referencing three studies as evidence. Let's dive in.
open.substack.com
September 27, 2025 at 6:11 PM
Which one should I do next? The big Swedish study that RFK & his buddies pretend doesn’t exist? Or one of the other 2 studies he mentioned at the press conference?
Vote by commenting!
Vote by commenting!
Reposted by Michael Tildahl
Delighted to share our work on replay and successor representations! We find replay during very short task pauses in human visual cortex that is linked to learning SRs & happens when learning is implicit. Study led by @lnnrtwttkhn.bsky.social
#compneuro #neuroskyence
www.pnas.org/doi/10.1073/...
#compneuro #neuroskyence
www.pnas.org/doi/10.1073/...
Replay in the human visual cortex during brief task pauses is linked to implicit learning of successor representations | PNAS
Humans can implicitly learn about multistep sequential relationships between events
in the environment from their statistical co-occurrence. Theore...
www.pnas.org
August 22, 2025 at 4:43 PM
Delighted to share our work on replay and successor representations! We find replay during very short task pauses in human visual cortex that is linked to learning SRs & happens when learning is implicit. Study led by @lnnrtwttkhn.bsky.social
#compneuro #neuroskyence
www.pnas.org/doi/10.1073/...
#compneuro #neuroskyence
www.pnas.org/doi/10.1073/...
Reposted by Michael Tildahl
New paper with @nathanieldaw.bsky.social in Nature Communications: an RL model that builds a successor map compositionally. The new model plans as well as the best models, and it links components of the map used for planning to neural codes in the medial entorhinal cortex.
rdcu.be/eAofi
rdcu.be/eAofi
Reconciling flexibility and efficiency: medial entorhinal cortex represents a compositional cognitive map
Nature Communications - How the brain creates compositional cognitive maps that support both flexible and efficient planning remains poorly understood. Here, authors propose a...
rdcu.be
August 12, 2025 at 5:18 PM
New paper with @nathanieldaw.bsky.social in Nature Communications: an RL model that builds a successor map compositionally. The new model plans as well as the best models, and it links components of the map used for planning to neural codes in the medial entorhinal cortex.
rdcu.be/eAofi
rdcu.be/eAofi
Reposted by Michael Tildahl
Some similarities matter, others don’t—a great Labatut book with a yellow cover means books by Labatut are good, not yellow books are good. Factorized representations support such selective generalization. Check out our study on select. gen. by Sam HallMcMaster in collab with @gershbrain.bsky.social
Entorhinal cortex signals dimensions of past experience that can be generalised in a novel environment https://www.biorxiv.org/content/10.1101/2025.08.01.668096v1
August 2, 2025 at 10:00 PM
Some similarities matter, others don’t—a great Labatut book with a yellow cover means books by Labatut are good, not yellow books are good. Factorized representations support such selective generalization. Check out our study on select. gen. by Sam HallMcMaster in collab with @gershbrain.bsky.social
Reposted by Michael Tildahl
Excited to share a new preprint w/ @annaschapiro.bsky.social! Why are there gradients of plasticity and sparsity along the neocortex–hippocampus hierarchy? We show that brain-like organization of these properties emerges in ANNs that meta-learn layer-wise plasticity and sparsity. bit.ly/4kB1yg5
A gradient of complementary learning systems emerges through meta-learning
Long-term learning and memory in the primate brain rely on a series of hierarchically organized subsystems extending from early sensory neocortical areas to the hippocampus. The components differ in t...
bit.ly
July 16, 2025 at 4:15 PM
Excited to share a new preprint w/ @annaschapiro.bsky.social! Why are there gradients of plasticity and sparsity along the neocortex–hippocampus hierarchy? We show that brain-like organization of these properties emerges in ANNs that meta-learn layer-wise plasticity and sparsity. bit.ly/4kB1yg5
Reposted by Michael Tildahl
Reposted by Michael Tildahl
Pleased to say that our story of how a theory of self-supervised learning in cortical layers accounts for several experimental observations is now out 🎉
www.nature.com/articles/s41...
www.nature.com/articles/s41...
Self-supervised predictive learning accounts for cortical layer-specificity - Nature Communications
How the cortex learns an internal representation of the world and why the cortex relies on a layered structure remain poorly understood. Here, the authors propose a computational theory in which the n...
www.nature.com
July 4, 2025 at 5:17 PM
Pleased to say that our story of how a theory of self-supervised learning in cortical layers accounts for several experimental observations is now out 🎉
www.nature.com/articles/s41...
www.nature.com/articles/s41...
Reposted by Michael Tildahl
This is an excellent and very clear piece from Sergey Levine about the strengths and limitations of Large Language models.
sergeylevine.substack.com/p/language-m...
sergeylevine.substack.com/p/language-m...
Language Models in Plato's Cave
Why language models succeeded where video models failed, and what that teaches us about AI
sergeylevine.substack.com
June 12, 2025 at 4:30 PM
This is an excellent and very clear piece from Sergey Levine about the strengths and limitations of Large Language models.
sergeylevine.substack.com/p/language-m...
sergeylevine.substack.com/p/language-m...
Reposted by Michael Tildahl
Pleased to say "Space, Time, and Memory", an academic book by Oxford University Press edited by the inimitable Lynn Nadel & Sara Aronowitz is now out.
I contributed a chapter, "Memory and Planning in Brains and Machines".
You can download the entire book for free:
library.oapen.org/bitstream/ha...
I contributed a chapter, "Memory and Planning in Brains and Machines".
You can download the entire book for free:
library.oapen.org/bitstream/ha...
June 9, 2025 at 8:48 PM
Pleased to say "Space, Time, and Memory", an academic book by Oxford University Press edited by the inimitable Lynn Nadel & Sara Aronowitz is now out.
I contributed a chapter, "Memory and Planning in Brains and Machines".
You can download the entire book for free:
library.oapen.org/bitstream/ha...
I contributed a chapter, "Memory and Planning in Brains and Machines".
You can download the entire book for free:
library.oapen.org/bitstream/ha...
Reposted by Michael Tildahl
Sharing a new paper from the lab. This paper, led by Sangyoon Ko, represents a merging of two longstanding research themes in the lab-- adult neurogenesis and systems consolidation.
rdcu.be/el18q
A short thread follows for those interested.
1/n
rdcu.be/el18q
A short thread follows for those interested.
1/n
Systems consolidation reorganizes hippocampal engram circuitry
Nature - A study shows that loss of memory precision associated with systems consolidation can be explained by neurogenesis-dependent reorganization of engram circuitry within the hippocampus over...
rdcu.be
May 14, 2025 at 4:32 PM
Sharing a new paper from the lab. This paper, led by Sangyoon Ko, represents a merging of two longstanding research themes in the lab-- adult neurogenesis and systems consolidation.
rdcu.be/el18q
A short thread follows for those interested.
1/n
rdcu.be/el18q
A short thread follows for those interested.
1/n
Reposted by Michael Tildahl
Top-down feedback is ubiquitous in the brain and computationally distinct, but rarely modeled in deep neural networks. What happens when a DNN has biologically-inspired top-down feedback? 🧠📈
Our new paper explores this: elifesciences.org/reviewed-pre...
Our new paper explores this: elifesciences.org/reviewed-pre...
Top-down feedback matters: Functional impact of brainlike connectivity motifs on audiovisual integration
elifesciences.org
April 15, 2025 at 8:11 PM
Top-down feedback is ubiquitous in the brain and computationally distinct, but rarely modeled in deep neural networks. What happens when a DNN has biologically-inspired top-down feedback? 🧠📈
Our new paper explores this: elifesciences.org/reviewed-pre...
Our new paper explores this: elifesciences.org/reviewed-pre...
Reposted by Michael Tildahl
Science is under threat in the US. @elife.bsky.social have commissioned a series of articles discussing the implications and what we can do. The first three articles are now live. More to follow:
elifesciences.org/articles/106...
elifesciences.org/articles/106...
elifesciences.org/articles/106...
elifesciences.org/articles/106...
elifesciences.org/articles/106...
elifesciences.org/articles/106...
Science Under Threat in the United States: How scientists and institutions should respond
Individual researchers and university leaders need to make the case for science to their elected representatives and to the public at large.
elifesciences.org
March 25, 2025 at 2:24 PM
Science is under threat in the US. @elife.bsky.social have commissioned a series of articles discussing the implications and what we can do. The first three articles are now live. More to follow:
elifesciences.org/articles/106...
elifesciences.org/articles/106...
elifesciences.org/articles/106...
elifesciences.org/articles/106...
elifesciences.org/articles/106...
elifesciences.org/articles/106...
Reposted by Michael Tildahl
After a super fun discussion on a visit to Harvard last week, this emerged as the critical unknown (at least between me and Sam!) in ideas of intracellular memory. If rich memories are stored intracellularly, each cell needs to be able to recapitulate its inputs during the memory.
Question for my neurobiology colleagues: what (if any) information do second messengers in neurons carry about their specific synapse of origin? In other words, if I were to measure only molecular signals in the soma, to what extent could I resolve a specific pattern of synaptic activation?
March 16, 2025 at 9:54 PM
After a super fun discussion on a visit to Harvard last week, this emerged as the critical unknown (at least between me and Sam!) in ideas of intracellular memory. If rich memories are stored intracellularly, each cell needs to be able to recapitulate its inputs during the memory.
Reposted by Michael Tildahl
I am incredibly proud to share my first, first-author paper as a postdoc with @benhayden.bsky.social . How does the human hippocampus, known for encoding concepts, represent the meanings of words while listening to narrative speech?
www.biorxiv.org/content/10.1...
www.biorxiv.org/content/10.1...
February 27, 2025 at 8:17 PM
I am incredibly proud to share my first, first-author paper as a postdoc with @benhayden.bsky.social . How does the human hippocampus, known for encoding concepts, represent the meanings of words while listening to narrative speech?
www.biorxiv.org/content/10.1...
www.biorxiv.org/content/10.1...
Reposted by Michael Tildahl
Jon whips out his trusty calculator to identify where America’s waste, fraud, and abuse really is
February 25, 2025 at 7:42 PM
Jon whips out his trusty calculator to identify where America’s waste, fraud, and abuse really is
Reposted by Michael Tildahl
💯👇
Boycott for-profit publishers!
They're stealing research $$$, don't provide any value added while making us do work for free (reviewer, editor) AND selling our private data to immigration agencies, foreign govts and who knows who else... It's criminal to support them!
Support nonprofit! 🧠💪
Boycott for-profit publishers!
They're stealing research $$$, don't provide any value added while making us do work for free (reviewer, editor) AND selling our private data to immigration agencies, foreign govts and who knows who else... It's criminal to support them!
Support nonprofit! 🧠💪
Elsevier/RELX profit rises 10%, investor call: "continuing to see strong growth" including from pay-to-read and pay-to-publish. From the www.journalology.com newsletter.
In my opinion, more researchers and universities need to stop supporting them.
In my opinion, more researchers and universities need to stop supporting them.
February 24, 2025 at 12:00 AM
💯👇
Boycott for-profit publishers!
They're stealing research $$$, don't provide any value added while making us do work for free (reviewer, editor) AND selling our private data to immigration agencies, foreign govts and who knows who else... It's criminal to support them!
Support nonprofit! 🧠💪
Boycott for-profit publishers!
They're stealing research $$$, don't provide any value added while making us do work for free (reviewer, editor) AND selling our private data to immigration agencies, foreign govts and who knows who else... It's criminal to support them!
Support nonprofit! 🧠💪
Reposted by Michael Tildahl
honestly same
The pandas got into some wild mushrooms. One of them’s been screaming at his paw for an hour.
February 12, 2025 at 7:14 AM
honestly same