Bowen Zheng's Avatar

Bowen Zheng

@bwz-brain.bsky.social

MIT BCS | grad part-time reductionist, full time human

61 Followers  |  176 Following  |  4 Posts  |  Joined: 17.11.2024  |  2.2518

Latest posts by bwz-brain.bsky.social on Bluesky

Preview
Explosive neural networks via higher-order interactions in curved statistical manifolds - Nature Communications Higher-order interactions shape complex neural dynamics but are hard to model. Here, authors use a generalization of the maximum entropy principle to introduce a family of curved neural networks, reve...

Our paper just out in Nature Communications!
www.nature.com/articles/s41...

We introduce curved neural networks naturally introducing high-order interactions showing:
β€’ explosive phase transitions
β€’ enhanced memory retrieval via self-annealing
β€’ increased memory capacity through geometric curvature

24.07.2025 10:24 β€” πŸ‘ 23    πŸ” 8    πŸ’¬ 1    πŸ“Œ 0
Post image

So what drives drift? We looked closely at the neurons and found that a small group of them were stable. These stable neurons were more excitable than neighboring cells, making the fate of the cells predictable.

23.07.2025 16:15 β€” πŸ‘ 6    πŸ” 2    πŸ’¬ 1    πŸ“Œ 0
The Lemkin Institute for Genocide Prevention is
calling on every single leader in the world: DO EVERYTHING YOU CAN TO GET FOOD &
WATER INTO GAZA RIGHT AWAY. Even if it takes bypassing the reports, meetings, endless conferences, parliamentary sessions, UN sessions, and all the other regular diplomatic
channels that have led nowhere. Just do it. Genocide must not be allowed to continue while we all
watch. We must not allow mass starvation in Gaza.
We cannot wait any longer. IF YOU HAVE POWER, USE IT. HISTORY WILL DEMONSTRATE THE RECTITUDE OF
YOUR ACTIONS.

The Lemkin Institute for Genocide Prevention is calling on every single leader in the world: DO EVERYTHING YOU CAN TO GET FOOD & WATER INTO GAZA RIGHT AWAY. Even if it takes bypassing the reports, meetings, endless conferences, parliamentary sessions, UN sessions, and all the other regular diplomatic channels that have led nowhere. Just do it. Genocide must not be allowed to continue while we all watch. We must not allow mass starvation in Gaza. We cannot wait any longer. IF YOU HAVE POWER, USE IT. HISTORY WILL DEMONSTRATE THE RECTITUDE OF YOUR ACTIONS.

DO EVERYTHING YOU CAN TO GET FOOD AND WATER IN TO GAZA.
This is from Lemkin Institute begging..... we are all begging.

21.07.2025 21:57 β€” πŸ‘ 622    πŸ” 409    πŸ’¬ 7    πŸ“Œ 10
Preview
Formation of an expanding memory representation in the hippocampus - Nature Neuroscience Multiday imaging of CA1 neurons during learning reveals that the representation stabilizes as the number of readily retrievable, information-rich and stable place cells increases and suggests novel me...

Really interesting results, suggesting that long-term place field stability is not from long-lasting synaptic plasticity, but is instead from an increased *probability of plasticity induction* in subsequent days.

17.07.2025 12:14 β€” πŸ‘ 42    πŸ” 9    πŸ’¬ 1    πŸ“Œ 0

β€œthis is an unfair comparison because the model has not been trained on all data that has ever existed and on all future data that will be digitalized! Our foundation model is omniscient which renders the concept of generalization null!!!!”

16.07.2025 19:16 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
Preview
Model mimicry limits conclusions about neural tuning and can mistakenly imply unlikely priors Nature Communications - Model mimicry limits conclusions about neural tuning and can mistakenly imply unlikely priors

Who doesn't like a good model of the brain? Yet, from simple regression to neural nets, some limitations keep popping up (e.g., overfitting) @mjwolff.bsky.social & I saw some cool but puzzling data, ran a quick analysis & found one such limitation: model mimicry. Now in #naturecommunications &🧡below

02.07.2025 08:50 β€” πŸ‘ 63    πŸ” 22    πŸ’¬ 1    πŸ“Œ 0
Post image

My latest Aronov lab paper is now published @Nature!

When a chickadee looks at a distant location, the same place cells activate as if it were actually there πŸ‘οΈ

The hippocampus encodes where the bird is looking, AND what it expects to see next -- enabling spatial reasoning from afar

bit.ly/3HvWSum

11.06.2025 22:24 β€” πŸ‘ 271    πŸ” 85    πŸ’¬ 10    πŸ“Œ 5

It occurred to me last night that microwaves are kinda like LLMs.
Remember when they first came out, people bought microwave cookbooks, and special vented plastic cookware, and they were going to change the way we cooked and ate forever?
Now we use them for defrosting mince, and reheating cold tea.

08.05.2025 08:39 β€” πŸ‘ 187    πŸ” 33    πŸ’¬ 11    πŸ“Œ 6

We’re excited about this project! We present a model of motor savings without the need for context.

02.04.2025 13:37 β€” πŸ‘ 13    πŸ” 5    πŸ’¬ 0    πŸ“Œ 0

Kilosort4 detects a LOT of neurons, I recorded 15k neurons in one year 🀯 Traditionally, one would curate these detected units to see if they are well isolated single neurons. This is not feasible anymore, so today let's look at three options that are out there to automate this process! πŸ€–πŸ‘‡

27.03.2025 10:38 β€” πŸ‘ 41    πŸ” 12    πŸ’¬ 2    πŸ“Œ 1
Preview
Technical Associate I, Kanwisher Lab MIT - Technical Associate I, Kanwisher Lab - Cambridge MA 02139

I’m hiring a full-time lab tech for two years starting May/June. Strong coding skills required, ML a plus. Our research on the human brain uses fMRI, ANNs, intracranial recording, and behavior. A great stepping stone to grad school. Apply here:
careers.peopleclick.com/careerscp/cl...
......

26.03.2025 15:09 β€” πŸ‘ 64    πŸ” 48    πŸ’¬ 5    πŸ“Œ 3
Preview
Synaptic plasticity rules driving representational shifting in the hippocampus - Nature Neuroscience Madar et al. report that behavioral timescale synaptic plasticity (BTSP), not spike-timing-dependent plasticity, explains heterogeneous place fields shifting in the hippocampus. The probability of BTS...

Behavioral timescale synaptic plasticity (BTSP), not Hebbian spike-timing-dependent plasticity (STDP), explains heterogenous place field shifting in the mouse hippocampus 🧠πŸ§ͺ

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

25.03.2025 15:40 β€” πŸ‘ 31    πŸ” 13    πŸ’¬ 0    πŸ“Œ 2

In contrast to the wide spread applause that this piece seems to be getting, I disagree with a lot of what is said here.

1/N

08.03.2025 11:41 β€” πŸ‘ 23    πŸ” 9    πŸ’¬ 3    πŸ“Œ 3
In order to understand cognition, we often recruit analogies as building blocks of theories to aid us in this quest. One such attempt, originating in folklore and alchemy, is the homunculus: a miniature human who resides in the skull and performs cognition. Perhaps surprisingly, this appears indistinguishable from the implicit proposal of many neurocognitive theories, including that of the 'cognitive map,' which proposes a representational substrate for episodic memories and navigational capacities. In such 'small cakes' cases, neurocognitive representations are assumed to be meaningful and about the world, though it is wholly unclear who is reading them, how they are interpreted, and how they come to mean what they do. We analyze the 'small cakes' problem in neurocognitive theories (including, but not limited to, the cognitive map) and find that such an approach a) causes infinite regress in the explanatory chain, requiring a human-in-the-loop to resolve, and b) results in a computationally inert account of representation, providing neither a function nor a mechanism. We caution against a 'small cakes' theoretical practice across computational cognitive modelling, neuroscience, and artificial intelligence, wherein the scientist inserts their (or other humans') cognition into models because otherwise the models neither perform as advertised, nor mean what they are purported to, without said 'cake insertion.' We argue that the solution is to tease apart explanandum and explanans for a given scientific investigation, with an eye towards avoiding van Rooij's (formal) or Ryle's (informal) infinite regresses.

In order to understand cognition, we often recruit analogies as building blocks of theories to aid us in this quest. One such attempt, originating in folklore and alchemy, is the homunculus: a miniature human who resides in the skull and performs cognition. Perhaps surprisingly, this appears indistinguishable from the implicit proposal of many neurocognitive theories, including that of the 'cognitive map,' which proposes a representational substrate for episodic memories and navigational capacities. In such 'small cakes' cases, neurocognitive representations are assumed to be meaningful and about the world, though it is wholly unclear who is reading them, how they are interpreted, and how they come to mean what they do. We analyze the 'small cakes' problem in neurocognitive theories (including, but not limited to, the cognitive map) and find that such an approach a) causes infinite regress in the explanatory chain, requiring a human-in-the-loop to resolve, and b) results in a computationally inert account of representation, providing neither a function nor a mechanism. We caution against a 'small cakes' theoretical practice across computational cognitive modelling, neuroscience, and artificial intelligence, wherein the scientist inserts their (or other humans') cognition into models because otherwise the models neither perform as advertised, nor mean what they are purported to, without said 'cake insertion.' We argue that the solution is to tease apart explanandum and explanans for a given scientific investigation, with an eye towards avoiding van Rooij's (formal) or Ryle's (informal) infinite regresses.

Figure 1 in https://philsci-archive.pitt.edu/24834/

Figure 1 in https://philsci-archive.pitt.edu/24834/

Box 1 in https://philsci-archive.pitt.edu/24834/

Box 1 in https://philsci-archive.pitt.edu/24834/

Box 2 in https://philsci-archive.pitt.edu/24834/

Box 2 in https://philsci-archive.pitt.edu/24834/

Tired but happy to say this is out w @andreaeyleen.bsky.social: Are Neurocognitive Representations 'Small Cakes'? philsci-archive.pitt.edu/24834/

We analyse cog neuro theories showing how vicious regress, e.g. the homunculus fallacy, is (sadly) alive and well β€” and importantly how to avoid it. 1/

01.03.2025 14:16 β€” πŸ‘ 239    πŸ” 75    πŸ’¬ 25    πŸ“Œ 18
β€œTorrenting from a corporate laptop doesn’t feel right”: Meta emails unsealed

β€œTorrenting from a corporate laptop doesn’t feel right”: Meta emails unsealed

A photo of Aaron Swartz (1986-2013) when he was 19.

A photo of Aaron Swartz (1986-2013) when he was 19.

Last month, Meta admitted to torrenting a controversial large dataset known as LibGen, which includes tens of millions of pirated books. But details around the torrenting were murky until yesterday, when Meta's unredacted emails were made public for the first time. The new evidence showed that Meta torrented "at least 81.7 terabytes of data across multiple shadow libraries through the site Anna’s Archive, including at least 35.7 terabytes of data from Z-Library and LibGen," the authors' court filing said. And "Meta also previously torrented 80.6 terabytes of data from LibGen."

Last month, Meta admitted to torrenting a controversial large dataset known as LibGen, which includes tens of millions of pirated books. But details around the torrenting were murky until yesterday, when Meta's unredacted emails were made public for the first time. The new evidence showed that Meta torrented "at least 81.7 terabytes of data across multiple shadow libraries through the site Anna’s Archive, including at least 35.7 terabytes of data from Z-Library and LibGen," the authors' court filing said. And "Meta also previously torrented 80.6 terabytes of data from LibGen."

Meta illegaly downloaded 80+ terabytes of books from LibGen, Anna's Archive, and Z-library to train their AI models.

In 2010, Aaron Swartz downloaded only 70 GBs of articles from JSTOR (0.0875% of Meta). Faced $1 million in fine and 35 years in jail. Took his own life in 2013.

07.02.2025 16:45 β€” πŸ‘ 7625    πŸ” 4104    πŸ’¬ 53    πŸ“Œ 172
Preview
Erika's quick-start guide to research nonprofits You do NOT need permission from a university to do research (!!)

A quick-start guide to research non-profits: erikaaldendeb.substack.com/p/erikas-qui...

31.01.2025 18:51 β€” πŸ‘ 9    πŸ” 3    πŸ’¬ 0    πŸ“Œ 0

Wow! I speculated a while back that OpenAI might be scanning API logs to get the hold-out questions on this dataset but now it seems the whole thing was secretly funded by OpenAI who had privileged access to the data.

Apparently I wasn't being cynical enough.

20.01.2025 01:05 β€” πŸ‘ 15    πŸ” 3    πŸ’¬ 1    πŸ“Œ 0

Neural signatures of model-based and model-free reinforcement learning across prefrontal cortex and striatum https://www.biorxiv.org/content/10.1101/2025.01.11.632388v1

12.01.2025 10:15 β€” πŸ‘ 19    πŸ” 10    πŸ’¬ 0    πŸ“Œ 1

I always come back to @romainbrette.bsky.social's point about the difference between details vs realism in models

journals.plos.org/ploscompbiol...

11.01.2025 15:00 β€” πŸ‘ 18    πŸ” 4    πŸ’¬ 1    πŸ“Œ 0

Maybe a good time to remember that mice have tiny hyperconnected brains. An estimated 97% of all possible connections between brain areas exist in mice, vs ~62% in macaques and marmosets.

No wonder everything is everywhere in mice, they have all-to-all connectivity!

doi.org/10.1093/cerc...

11.01.2025 16:37 β€” πŸ‘ 86    πŸ” 27    πŸ’¬ 2    πŸ“Œ 3
Post image

Pre-print 🧠πŸ§ͺ
Is mechanism modeling dead in the AI era?

ML models trained to predict neural activity fail to generalize to unseen opto perturbations. But mechanism modeling can solve that.

We say "perturbation testing" is the right way to evaluate mechanisms in data-constrained models

1/8

08.01.2025 16:33 β€” πŸ‘ 115    πŸ” 46    πŸ’¬ 4    πŸ“Œ 2
Preview
Cognition and Intractability A Guide to Classical and Parameterized Complexity Analysis

πŸ“– Cognition and Intractabilityβ€”A Guide to Classical and Parameterized Complexity Analysis

cognitionandintractability.com

26.12.2024 00:34 β€” πŸ‘ 30    πŸ” 8    πŸ’¬ 0    πŸ“Œ 0

Also if you watch the video in one visual field, then pause and shift the phone to another visual field, you don’t see the effect. But the effect comes back if you move the phone back to the initial point.

14.12.2024 14:04 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

if u fixate on the yellow dot after pausing the video, it seems like all dots are rotating at constant angular velocity. if u saccade to the corner, the dots are moving in a folding pattern.

14.12.2024 14:03 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Preview
Two Very Different Manhattan Murder Investigations The NYPD spent countless hours and resources searching for a CEO’s killer, but has made little evident progress on the fatal stabbing of a migrant teen.

As NYPD officials boasted of the resources expended finding the killer of a corporate CEO, another sidewalk murder the same week, of a migrant teen, has not received the same treatment. hellgatenyc.com/two-manhatta...

09.12.2024 22:19 β€” πŸ‘ 10584    πŸ” 4086    πŸ’¬ 180    πŸ“Œ 190

My hot take is that causality is overrated. Causality is something we settle for when we don’t have the full description of the mechanism. When two bodies interact according to physical laws, we don’t say one *causes* the other to move. I am hopeful that we can strive for something better. #hottake

30.11.2024 04:52 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

I worry that causal methods are our S-matrix theory: seductive in their generality but too general to make
headway on the problems we care about. 13/n

30.11.2024 02:21 β€” πŸ‘ 4    πŸ” 2    πŸ’¬ 2    πŸ“Œ 0

Sometimes I think the most important thing a computational neuroscientist can do to encourage acceptance of their work in the broader experimental community is just to plot their model data in the exact same way the relevant experimental data was plotted. It's very affecting!

25.11.2024 17:53 β€” πŸ‘ 104    πŸ” 10    πŸ’¬ 5    πŸ“Œ 5

Can we stop with the foundation model is all you need nonsense yet? #hottake 🧠

22.11.2024 01:47 β€” πŸ‘ 18    πŸ” 2    πŸ’¬ 1    πŸ“Œ 0

@bwz-brain is following 20 prominent accounts