Aniol Santo-Angles

How dynamics arise from the structure is my biggest interest. In this study, we started with a small step and asked how structure constrains dynamics. Spoiler: would that it were so simple… (1/6)

Our paper is out in @natneuro.nature.com!

www.nature.com/articles/s41...

We develop a geometric theory of how neural populations support generalization across many tasks.

@zuckermanbrain.bsky.social
@flatironinstitute.org
@kempnerinstitute.bsky.social

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𝗛𝗼𝘄 𝗱𝗼 𝗯𝗿𝗮𝗶𝗻 𝗮𝗿𝗲𝗮𝘀 𝗿𝗲𝗹𝗮𝘁𝗲𝗱 𝘁𝗼 𝗳𝘂𝗻𝗰𝘁𝗶𝗼𝗻?
"High-resolution activity maps of PFC did NOT align with cytoarchitecturally defined subregions."
Key tenet in neuroscience is that cytoarchitectonic boundaries correspond to functional ones.
NB: study in the mouse
#neuroskyence
doi.org/10.1038/s415...

With some trepidation, I'm putting this out into the world:
gershmanlab.com/textbook.html
It's a textbook called Computational Foundations of Cognitive Neuroscience, which I wrote for my class.

My hope is that this will be a living document, continuously improved as I get feedback.

notebook-sharing/bold-cmro2-cbf-r2.ipynb at master · alexhuth/notebook-sharing Contribute to alexhuth/notebook-sharing development by creating an account on GitHub.

My simulation is here if anyone wants to play with it: github.com/alexhuth/not...

BOLD signal changes can oppose oxygen metabolism across the human cortex - Nature Neuroscience Using quantitative brain imaging, the authors show opposite fMRI BOLD signal to metabolic activity due to variable oxygen extraction across the human cortex. This questions the canonical interpretatio...

Would love to hear expert views on this paper. It appears to show that the operationalization of brain activity the field has relied on for 3 decades—the BOLD response—is not actually a sensible measure of brain activity.

www.nature.com/articles/s41...

Rethinking the centrality of brain areas in understanding functional organization - Nature Neuroscience Parcellation of the cortex into functionally modular brain areas is foundational to neuroscience. Here, Hayden, Heilbronner and Yoo question the central status of brain areas in neuroscience from the ...

A must-read review. It argues that brain areas are only one of several organizing principles and are not especially central, given their weak correspondence to function. Cytoarchitecture and connectivity are a starting point, not the endpoint.
www.nature.com/articles/s41...
#neuroscience

Happy to share our new paper in @nathumbehav.nature.com: t.co/Ciq7AKvle5. Using 500k+ behavioral trials, we show that #serialdependence deviates from #Bayesian predictions, pointing to a new narrative about how recent experience shapes perception. @aozkirli.bsky.social @achetverikov.bsky.social

Doing a PhD is - at heart - one long discussion with your mentor. The discussion changes over time - with unexpected turns and ups & downs - but through it all is a pair of people discussing a topic endlessly to make sense of it.
PhD students: choose someone you like to talk to!

BOLD signal changes can oppose oxygen metabolism across the human cortex, Nature Neuroscience

fMRI signals “up,” but neural metabolism might be going “down.”

In our @natneuro.nature.com paper, we demonstrate that about 40% of voxels with robust BOLD responses exhibit opposite oxygen metabolism, revealing two distinct hemodynamic modes.

rdcu.be/eUPO8
funds @erc.europa.eu
#neuroskyence 🧵:

🚨 new preprint alert! biorxiv.org/content/10.1...

what is the architecture of an individual working memory?

1/n

Thanks to co-authors @YangJiarui2002 (X/twitter), Ying Zhou, @hannah-chu.bsky.social, @neurograce.bsky.social and @sreenivasanlab.bsky.social for their contributions to this work! 🎉

We found behaviorally relevant orthogonal subspaces during the retention period—replicating prefrontal intracranial results in non-human primates—but no evidence of sequential replay. This suggests the brain maintains sequences by transforming time into space!

Using broadband MEG with dimensionality reduction and multivariate decoding, we asked whether sequential items are preserved by replaying them in order or by organizing them into a low-dimensional neural manifold.

Neural Subspaces Encode Sequential Working Memory, but Neural Sequences Do Not The neural mechanisms of multiple-item working memory are not well understood. In the current study, we address two competing hypotheses about the neural basis of sequential working memory: neural sub...

New preprint! 🎉 We investigate how the brain maintains multiple items in working memory, testing two competing hypotheses for sequential memory: neural subspaces vs. neural sequences.
www.biorxiv.org/content/10.1...

It is actually an incredibly frustrating time to be a theoretical neuroscientist right now imo, for this reason

To those who access published (nonhuman) neurophysiology data & analysis code: what’s your favorite place to find it?

Hemispherotomy leads to persistent sleep-like slow waves in the isolated cortex of awake humans Hemispherotomy is a neurosurgical procedure for treating refractory epilepsy by disconnecting a significant portion of the cortex. This study shows that the isolated cortex exhibits EEG patterns resem...

Colombo et al., Plos Biology, "Hemispherotomy leads to persistent sleep-like slow waves in the isolated cortex of awake humans"

journals.plos.org/plosbiology/...

mitochondria from bipolar patients are closer to the nucleus in these images; control patients' are spread out further

15 years in the making, we confirmed that mitochondria - the powerhouse of the cell - have an unusual localization in patients who experience psychosis (including schizophrenia and bipolar disorders). You’ll never guess what kind of patient cells we used to make this discovery… 🧵

One mother for two species via obligate cross-species cloning in ants - Nature In a case of obligate cross-species cloning, female ants of Messor ibericus need to clone males of Messor structor to obtain sperm for producing the worker caste, resulting in males from the same mother having distinct genomes and morphologies.

It's never occurred to me that it IS an assumption. This is the most astonishing start to a paper I've read in years:

"Living organisms are assumed to produce same-species offspring. Here, we report a shift from this norm in Messor ibericus, an ant that lays individuals from two distinct species."

"Cognition is emergent" by Earl Miller YouTube video by Neuroscience & Philosophy Salon

Talk: Cognition is Emergent - Earl K. Miller
Neuroscience and Philosophy Salon, 9-12-25
youtu.be/Sk4ehOcsDmM?...

Will try!
But I'll say in advance that I view the mouse brain as very different. Their anatomical connectivity is very high, with almost the entire cortex interconnected. Something like 97% if the Kennedy figures are right. Experiments in primates and humans are needed but obvly cannot be done now.

Associative synaptic plasticity creates dynamic persistent activity In biological neural circuits, the dynamics of neurons and synapses are tightly coupled. We study the consequences of this coupling and show that it enables a novel form of working memory. In recurren...

(1/26) Excited to share a new preprint led by grad student Albert Wakhloo, with me and Larry Abbott: "Associative synaptic plasticity creates dynamic persistent activity."
www.biorxiv.org/content/10.1...

🚨New paper🚨

Neural manifolds went from a niche-y word to an ubiquitous term in systems neuro thanks to many interesting findings across fields. But like with any emerging term, people use it very differently.

Here, we clarify our take on the term, and review key findings & challenges rdcu.be/ex8hW

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...

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...

🧠📈 🧪

emotion wheel starting with "joy, fear, anger" in the center and then lapsing into gibberish

a friend of mine shared this ai-generated "emotion wheel" and unfortunately i have been laughing my ass off at it for like 15 minutes now. today i am feeling Fnliinneon

Because we must build good things while we scream about the bad, I have started a "Data for Good" team @data-for-good-team.bsky.social that partners with organizations needing short-term data science help. We have three projects ongoing & will add more as our capacity grows.
data-for-good-team.org

Depressed individuals often experience a profound slowing/standstill of time. Northoff argues this is due to a desynchronization between “self-time” (inner) and “world-time” (external); inner sense of time becomes abnormally slow, making external events feel overwhelmingly fast or unmanageable. This

It's kinda obvious. #AGIComics has already figured out which brain region is the most important. 😇

screenshot of preprint title

High-Dimensional Dynamics in Low-Dimensional Networks.

New preprint with a former undergrad, Yue Wan.

I'm not totally sure how to talk about these results. They're counterintuitive on the surface, seem somewhat obvious in hindsight, but then there's more to them when you dig deeper.