Alex Williams

News from central Jersey: I'm running to represent New Jersey's 12th Congressional District.

By entering the fray, I hope to bring ideas of repairing our frayed republic. Not only to defend it in 2026, but to build something stronger, for generations to come!

samwang.substack.com/p/entering-t...

New paper out at PNAS: www.pnas.org/doi/10.1073/...
Revisiting the high-dimensional geometry of population responses in the visual cortex with @jpillowtime.bsky.social. The review took forever because a reviewer was doubtful our new estimator can infer eigenvalues beyond the rank of the data! (1/6)

Complementary cortical and thalamic contributions to cell type–specific striatal activity dynamics during movement Cell type–specific striatal activity during movement is shaped by cortical and thalamic inputs with complementary roles.

Our new work is out in Science Advances. We show that neural activity in the striatum reflects not just cortical inputs, but also often-underappreciated thalamic inputs.

www.science.org/doi/10.1126/...

As tens of thousands across America protest the violence that ICE sows with impunity, federal agents shot and killed another person in Minneapolis today.

ICE terrorizes our cities. ICE puts us all in danger. Abolish ICE.

Screenshot of post reading: These are not rogue agents. This is an all out assault on American life. ICE is a criminal organization that is entering homes without judicial warrants, detaining witnesses, and killing people. All at the direction of Trump. We must stop funding DHS. There is no other path forward. Responding to post reading: The Tribune also says ICE has transported several witnesses into detention.

We must stop funding DHS.

At @elife.bsky.social you can now include explainer videos with every figure. Like going to a seminar while you engage with the paper. First example here elifesciences.org/articles/106...

Click the arrows next to each figure to get a video of @mathiassablemeyer.bsky.social explaining it for you!

i personally think “don’t fund the gestapo” is a relatively small ask in the face of an illegal violent occupation of a US city that has killed at least one citizen and terrorized countless more. any elected who cannot clear even that modest bar is dead to me

Leveraging insights from neuroscience to build adaptive artificial intelligence Nature Neuroscience - Adaptive intelligence envisions AI that, like animals, learns online, generalizes and adapts quickly. This Perspective reviews biological foundations, progress in AI and...

Interested in the latest advances in neuroscience (neural dynamics and internal models) and how they can be leveraged to build smarter, adaptive AI?

➡️ My first real solo piece 🖤🫶 @natneuro.nature.com

rdcu.be/eWVmA

The recent days have been horrific. We can't become numb to repeated instances of illegal and unconstitutional action by government agencies. It's even worse when public officials are blatantly lying in ways that contradict dozens of pieces of video evidence.

By the way, if you’re interested in working together on problems like this, I’m starting my lab at UCSF this summer. Get in touch if you’re interested in doing a postdoc! More info here: wj2.github.io/postdoc_ad (7/7)

Registration Deadline: Sunday, January 18 at 5:00 PM (London time). Notification: We will notify applicants of the outcome by the end of January.

We're excited for the Pre-COSYNE 2026 Brainhack! March 10–11 in Lisbon 🇵🇹

We'll be using CON²PHYS: same dataset, same questions, many truths?

🔹2 days
🔹team-based
🔹real ephys data
🔹open tools
🔹mini-presentations
🔹all skill levels

Apply now! 👇👇👇
pre-cosyne-brainhack.github.io/hackathon202...

📣 Pre-COSYNE Brainhack 2026 – Join Us in Lisbon! 🧠✨
March 10–11, 2026 • Lisbon, Portugal

pre-cosyne-brainhack.github.io/hackathon2026

Kick off COSYNE week with two days of hands-on, team-based hacking around real electrophysiology data!

✅ Apply now via the event website (limited spots).

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.

The “prosecute the former regime at every level” candidate has my vote in 2028.

Ontogeny of the spinal cord dorsal horn The dorsal horn of the mammalian spinal cord is organized into laminae where each layer is populated by different neuron types, has distinctive circuit connections, and plays specialized roles in beha...

Excited to share @rbrianroome.bsky.social ‘s beautiful paper on development of the dorsal horn of the mouse spinal cord @science.org

This is how the anatomical organization and cell types that process pain, touch, body position and more are laid down.

www.science.org/doi/10.1126/...

also by shooting people. that's especially unsafe, I feel

We introduce epiplexity, a new measure of information that provides a foundation for how to select, generate, or transform data for learning systems. We have been working on this for almost 2 years, and I cannot contain my excitement! arxiv.org/abs/2601.03220 1/7

Careers Careers on Simons Foundation

Joint junior faculty position in Computational Neuroscience, between Ctr for Computational Neuroscience at @flatironinstitute.org and the CUNY Graduate Center @thegraduatecenter.bsky.social . Application deadline: 16 Jan 2026!

www.simonsfoundation.org/flatiron/car...
cuny.jobs/new-york-ny/...

Neural representations of visual memory in inferotemporal cortex reveal a generalizable framework for translating between spikes and field potentials Translating neurophysiological findings requires understanding the relationship between common measures of brain activity in animals (spiking activity) and humans (local field potentials, LFP). Prior ...

🚨 New preprint!

Why do some insights from spikes translate to field potentials while others don't? In this paper we compare visual memory representations in spikes and LFPs to propose a general framework that answers this question.

www.biorxiv.org/content/10.6...

🧵 (1/10)

🧠🟦 🧠💻

Comically over-lawyered and under-inspiring. Just resign, man. Take a lobbying job or something.

This is why Democrats look to a mayor like Zohran Mamdani for national leadership.

🥴

first as tragedy then as farce. then as farce again. then farce one more time. a little more farce after that. then some farce. and then another farce and more farce after

Highlights of 2025

Ayesha Vermani defended her PhD thesis this year. She helped jump start a new direction in integrative neuroscience:

Vermani et al. (2025), Meta-dynamical state space models for integrative neural data analysis. ICLR
👉 openreview.net/forum?id=SRp...
👉 youtu.be/SiXxPmkpYF8

Interpretable Embeddings with Sparse Autoencoders: A Data Analysis Toolkit Analyzing large-scale text corpora is a core challenge in machine learning, crucial for tasks like identifying undesirable model behaviors or biases in training data. Current methods often rely on cos...

I keep telling this to students. If you really want to do SAE research, just find a great classic paper on topic modeling and reimplement it using SAEs. I don’t think anyone would really notice.

Dimensionality reduction may be the wrong approach to understanding neural representations. Our new paper shows that across human visual cortex, dimensionality is unbounded and scales with dataset size—we show this across nearly four orders of magnitude. journals.plos.org/ploscompbiol...

Simons Foundation Now Accepting Applications for Workshop on Canonical Cortical Computations Simons Foundation Now Accepting Applications for Workshop on Canonical Cortical Computations on Simons Foundation

Applications are due in one month for our Workshop on Canonical Cortical Computations: https://www.simonsfoundation.org/2025/11/13/simons-foundation-now-accepting-applications-for-workshop-on-canonical-cortical-computations/ #science #neuroscience

At #NeurIPS2025!

🎉 Excited to present Conditionally Linear Dynamical Systems (CLDS). We leverage the dependence of neural dynamics on task covariates to yield an interpretable, flexible model of dynamics.

Come meet and check it out!
📍: Poster #2209, Hall C,D,E on Thu Dec 4, 11 am–2 pm, PST.

🧵/6

This is joint work with amazing collaborators: Amin Nejatbakhsh (@aminejat.bsky.social), David Lipshutz (
@lipshutz.bsky.social), Jonathan Pillow (@jpillowtime.bsky.social), and Alex Williams (@itsneuronal.bsky.social).

🔗 OpenReview: openreview.net/forum?id=xgm...
🖥️ Code: github.com/neurostatsla...

We are excited to announce that the Cognitive Computational Neuroscience meeting (CCN 2026) will be held at New York University from August 3–6, 2026.
2026.ccneuro.org

We are opening a FACULTY POSITION (tenure track, permanent) in the University of Cambridge at the interface of control and biology, interpreted broadly. Theorists and wet lab quantitative biologists with backgrounds in control, EE, applied math, ... apply by Jan 28!

www.cam.ac.uk/jobs/univers...