Johannes Kappel

Come on Konrad, why do you cave so easily? Here, let me try it for you:
1. Spikes are (to good approximation) the only events that matter.
2. Extracellular fields are one way by which spikes interact with each other.
1/2

"[...], in principle, the humans on our team could have come up with it unaided. Nevertheless, we only found it after constructing the AI system."

Capitalism certainly does not fund science to speak truth to power. But precisely because science cannot make due without a concept of truth, it sometimes cannot help but speak truth to power anyways. An obvious case is climate change, where scientific truth conflicts clearly with the profit motive.

Jeff Bezos Creates A.I. Start-Up Where He Will Be Co-Chief Executive

In applying AI to material science, biology, etc, capitalism is trying to shed science.

The point is to substitute the engineering of a machine that can generate what science has hitherto done, but without having people know things. Knowledge ultimately residing in private property is the dream.

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

What is the most profitable industry in the world, this side of the law? Not oil, not IT, not pharma.

It's *scientific publishing*.

We call this the Drain of Scientific Publishing.

Paper: arxiv.org/abs/2511.04820
Background: doi.org/10.1162/qss_...

Thread @markhanson.fediscience.org.ap.brid.gy 👇

Artificial Intelligence Wants to Sell You Stuff While the World Burns Meta is betting on generative AI for a new generation of aggressive advertising. It requires immense energy, much of which will likely come from fossil fuels.

To me, this is one of the key aspects of generative AI's broader environmental, social and climate harm: it cannot exist in an efficient, lean and narrowly applied way.

It only ever looks like it "works" when it's brute-forced: just like Bitcoin. The harm is baked into its characteristics.

Three panel thing. In the left panel we use error bars. In the second, we take statistical significance as the biggest number but still have error bars. In LLM science, we just have the biggest number

What if we did a single run and declared victory

MIT rejects "compact" proposed by the Trump administration.
MIT prez wrote: it "would restrict freedom of expression and our independence as an institution" and "is inconsistent with our core belief that scientific funding should be based on scientific merit alone."
orgchart.mit.edu/letters/rega...

Looking forward to what’s coming from your lab, congrats 🙂

a man wearing a white shirt and tie smiles in front of a window ALT: a man wearing a white shirt and tie smiles in front of a window

I've been waiting some years to make this joke and now it’s real:

I conned somebody into giving me a faculty job!

I’m starting as a W1 Tenure-Track Professor at Goethe University Frankfurt in a week (lol), in the Faculty of CS and Math

and I'm recruiting PhD students 🤗

You asked for it! We delivered Quack-O-Grams to our members of Congress urging them to #ImpeachRFK, and get that Quack out of office!

There's still time for you to get in on this fluffy, feathery action: Send your own duck at zurl.co/W1ZnB and keep the momentum going! 🦆

Only single cell sequencing of the all these post docs will reveal why

Preprint -
Excited to present WHOLISTIC, which extends the concept of whole-brain functional imaging to the entire body. Pioneering work by incredibly talented Virginia Ruetten @vmsruetten.bsky.social, this platform reveals whole-organism cellular dynamics in vivo.
www.biorxiv.org/content/10.1...

‪@benhayden.bsky.social‬
@tyrellturing.bsky.social‬
@jmgrohneuro.bsky.social‬
@pessoabrain.bsky.social
I see a lot of talk on here about how we should avoid
"x does y" talk because the brain is "a dynamic, reverberant, reciprocally interconnected system".
But this does not follow.
A thread...

A brain-wide map of neural activity during complex behaviour - Nature The International Brain Laboratory presents a brain-wide electrophysiological map obtained from pooling data from 12 laboratories that performed the same standardized perceptual decision-making task i...

Sad day for peope who still believe brain areas are the primary organizational units of function in the brain.

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

I hope that when RFK Jr dies someday, someone has been hired and trained to capture whatever crawls out of the body, so that it doesn't find a new host

I wrote a Comment on neurotheory, and now you can read it!

Some thoughts on where neurotheory has and has not taken root within the neuroscience community, how it has shaped those subfields, and where we theorists might look next for fresh adventures.

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

The Incompatibilities Between Generative AI and Art: Q&A with Ted Chiang The Incompatibilities Between Generative AI and Art: Q&A with Ted Chiang

"Your job is not to turn in completed assignments; it's to learn how to think."

cdh.princeton.edu/blog/2025/08...

Total disaster for the #drosophila community if flybase disappears

Never ask postdocs what they'll be doing next year, that's considered terribly offensive in their culture.

📰 I really enjoyed writing this article with @thetransmitter.bsky.social! In it, I summarize parts of our recent perspective article on neural manifolds (www.nature.com/articles/s41...), with a focus on highlighting just a few cool insights into the brain we've already seen at the population level.

Photo of a sketch of a Neanderthal. The headline reads: Scientists Growing Neanderthal 'Minibrains', Will Connect Them to Crab Robots

Go for it. I don't even care any more.

An integrated single-nucleus and spatial transcriptomics atlas reveals the molecular landscape of the human hippocampus - Nature Neuroscience The topographical organization of cells in the hippocampus reflects its ability to regulate mood and cognition. Here the authors generate a spatially resolved gene expression map in the human hippocam...

Great resource, out today in @natneuro.nature.com:
An integrated single-nucleus and spatial transcriptomics atlas reveals the molecular landscape of the human hippocampus
@stephaniehicks.bsky.social @martinowk.bsky.social & colleagues
🧪🧠🧬
www.nature.com/articles/s41...

Joint statement on Gaza from AFP, AP, BBC News and Reuters

Wake up, babe. A new mapping stimulus just dropped.

Yay 🙌 congrats Felix!!

🚨Very happy that my PhD work is now out in @nature.com!

We discovered that evolution, by acting in the midbrain, shifted the threshold to escape in Peromyscus mice, to fine-tune defensive strategies in different environments

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

This was a truly collaborative effort! 🧵⬇️

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...

🧠📈 🧪

Proposal recommended for funding! Which means we have a fresh, 3-year-funded position available for a computational postdoc interested in studying dynamics of social interactions in rats, with simultaneous Neuropixels data to follow 🐀🐀🐀

Proper job ad pending, but email me if interested!