If an action results in error, each neuron requires an individualized teaching signal that guides change in its output. This is the credit assignment problem of learning. Are there neurons in the brain that can compute such a sophisticated teaching signal? Yes. www.biorxiv.org/content/10.6...

Climbing fibers encode the gradient of a loss function for the cerebellum

Neurons in the brain are often many synapses away from motoneurons, yet if a movement results in error, each distant neuron needs a teacher that considers its specific contribution to production of th...

biorxiv.org

This is a really interesting and important study: www.nature.com/articles/s41... However, isn't it concerning that sweeping conclusions about functional organization of cortex are being reached on the basis of a single task?

Rarely categorical, highly separable representations along the cortical hierarchy - Nature

Cortical circuits prioritize diversity over categorical structure, supporting a computational regime geared towards high-dimensional, highly separable neural representations.

nature.com

New preprint from the lab! “A number simplex in the human medial temporal lobe” led by @hanlin-zhu.bsky.social 🧵 www.biorxiv.org/content/10.6...

A number simplex in the human medial temporal lobe

Humans handle numbers nimbly, suggesting a richer neural manifold structure than the prevalent mental number line model. In populations of medial temporal lobe (MTL) neurons in humans performing two s...

biorxiv.org

I am happy to share our latest manuscript, led by newly-minted PhD Justin Wang, identifying a neural population that selectively controls hedonic, but not homeostatic, feeding. www.biorxiv.org/content/10.6...

Ventral pallidal GABAergic neurons control hedonic feeding and obesity

Food intake is governed by two interacting drives. The homeostatic hunger drive regulates food intake to fulfill caloric needs while the hedonic drive promotes intake of palatable foods outside of cal...

biorxiv.org

Excited to share this work, led by Andrew Zimnik and Sherry An, from @mchurchland.bsky.social and my labs! www.cell.com/neuron/fullt... 1/2

Sparse component analysis: A method that uncovers separable computations within neural population activity

Zimnik et al. provide a new, interpretable, unsupervised dimensionality approach for neural population activity. Their approach, sparse component analysis (SCA), reveals the latent factors correspondi...

cell.com

🚨 Big news 🚨 After 10 years at Harvard, my lab is moving to Barcelona in Spring 2027 to join @cbc-upf.bsky.social and the Department of Engineering at @upf.edu. 1/4

Ecological Visual Processing in the Mouse - with @michaelgoard.bsky.social @crisniell.bsky.social @mbeyeler.bsky.social Visual computations that are engaged in ecological contexts: active sensing, motion processing, scene analysis, distance estimation, and spatial perception. doi.org/10.1146/annu...

Introducing the International Brain Lab AI Agent: a tool to help researchers analyze neural activity from across the mouse brain, using AI coding agents. Please try it! We would love your feedback. github.com/int-brain-la...

AI may soon enable researchers to generate high-quality science at a previously unimaginable speed. The effects for researchers will be as disruptive as industrial mass production was for artisan manufacturers, writes @kenneth-harris.bsky.social. #neuroskyence www.thetransmitter.org/artificial-i...

Mass-produced science is coming. What happens to scientists?

Artificial intelligence may soon enable researchers to generate high-quality science at a previously unimaginable speed.

thetransmitter.org

AI is about to transform how scientific research happens, and neuroscience is no exception. What the future looks like is up to us. I don’t have the answers; here are some thoughts from working on the IBL AI agent. Aiming to start a discussion.

Kenneth Harris@kenneth-harris.bsky.social · 3mo ago

Introducing the International Brain Lab AI Agent: a tool to help researchers analyze neural activity from across the mouse brain, using AI coding agents. Please try it! We would love your feedback. github.com/int-brain-la...

I’m honored to be recognized by the @AsteraInstitute as one of the highlighted essays in the essay competition! If you’re interested, I’d love for you to give it a read and share your thoughts! astera.org/essay-compet...

NEW: A serious staffing shortage — of the Trump admin's own making — is delaying the agency's ability to send billions to universities around the country, leaving labs reeling in the meantime. “I thought we were at rock bottom”, a senior NIH official said. “We are below rock bottom now.”

NIH staffing shortage could slash number of new grants issued this year

Some units at the US funding giant are so understaffed, they are focusing on mandated grant renewals rather than new awards.

nature.com

🥳 Super excited to share our lab's first preprint, led by @hungyun.bsky.social "Distinct tasks engage shared neural subspaces in human hippocampus and anterior cingulate cortex" www.biorxiv.org/content/10.6... 🧵(1/9)

Huge congrats to @snierwetberg.bsky.social , David (not on BSky), and @maxwellxchen.bsky.social for their paper! They developed a mouse task in which relational structure can be isolated from cue identity and reward statistics. www.biorxiv.org/content/10.6... 🧠📈🧪 #neuroskyence @uclnpp.bsky.social

New preprint led by recent PhD graduate Dalton Fitzgerald characterizing two distinct populations of VTA dopamine neurons that differ in ion channel expression, intrinsic excitability, and response to drugs of abuse. www.biorxiv.org/content/10.6...

How can a single cell learn without a brain? We explore this in my paper with @wallaceucsf.bsky.social! We discovered that single cells may learn using molecules similar to those that animal brains use to learn, like CaMKII. Cells can also propagate memory states to their progeny!

New work w/ Zach Kelso and @madeleinecsnyder.bsky.social www.biorxiv.org/content/10.6... Our negative results on classical conditioning in planarian flatworms. This was surprising, given the long history of work (including sensational findings of memory transfer and retention through decapitation).

"Although animals in natural environments accumulate a wide range of experiences that allow them to calibrate threat assessment, most behavioral studies of anxiety rely on laboratory animals housed in static, impoverished conditions." 🔥 www.cell.com/current-biol...

Transfer to a naturalistic setting restructures fear responses in laboratory mice

Zipple et al. show that transferring laboratory mice to naturalistic outdoor enclosures prevents and even reverses a canonical anxiety phenotype in rodents. The findings underscore the value of studyi...

cell.com

New paper in collaboration with @mhburrell.bsky.social @naoshigeuchida.bsky.social and @gershbrain.bsky.social ! "Phasic dopamine drives conditioned responding beyond its role in learning" 🧵 (1/8) www.biorxiv.org/content/10.6...

Pleased to share our new study showing how different cell types in the paratenial thalamus interact with the medial prefrontal cortex and other brain regions, all done by my graduate student Nigel Dao: www.biorxiv.org/content/10.6...

Delighted to share our discoveries about one of the brain's neurotransmitter systems: www.biorxiv.org/content/10.6... Together with colleagues at the @alleninstitute.org, we have learned a lot about a tiny cluster of neurons in the brainstem locus coeruleus (LC) that releases norepinephrine (NE). 1

New this year: free trainee pre-conference on July 13 organized by @cehaeffner.bsky.social @adanyajohnson.bsky.social Pre-conference tickets are free for main conference attendees but space is limited to 75 people so register early! www.cpconf.org/faq-cpconf20...

How can machines achieve the kind of flexible learning mastered by our brains? That’s what our own @neurokim.bsky.social is trying to find out! Learn more about ARNI’s work on natural and artificial intelligence: youtu.be/gM8YCaiAWrc?... #BrainAwarenessWeek

ARNI: Memory Driven Learning with Kim Stachenfeld

YouTube video by Columbia Engineering

youtu.be

@jhennig.bsky.social has shown that dopamine exerts a real-time effect on conditioned responding, beyond its role in learning: www.biorxiv.org/content/10.6... Another indication that dopamine is more than a learning signal! A joint effort with @naoshigeuchida.bsky.social and @mhburrell.bsky.social.

Thrilled to share our new paper, which shows that the relative timing of cholinergic and dopamine release dynamically gates whether dopamine acts as an RPE for in vivo plasticity and reinforcement learning. www.nature.com/articles/s41...

Acetylcholine demixes heterogeneous dopamine signals for learning and moving

Nature Neuroscience - Jang et al. measured dopamine and acetylcholine release in the striatum of rats performing a decision-making task and found that the relative timing of cholinergic and...

nature.com

🧵 New preprint led by @bingbrunton.bsky.social, @elliottabe.bsky.social, @lawrencehu.bsky.social We gave a worm brain control of a fly body and it walked What did we learn? Nothing, other than deep reinforcement learning is effective We call it the digital sphinx www.biorxiv.org/content/10.6...

A remarkable journey of resilience and transformation, from the chaotic corridors of group homes to the halls of Columbia and Stanford, EMERGENCE is a coming-of-age tale where heartbreak and humor meet the scientific wonder of modern artificial intelligence. 🔗 Preorder: tinyurl.com/fzcxb5ea

Mammals have hundreds of joints and muscles. Controlling them individually would be nearly impossible. How does the nervous system organize such complexity into coherent actions? Our new study explores this question through a natural behavior: jumping.

The deadline for applying to the Methods in Computational Neuroscience summer course at MBL in Woods Hole is approaching (March 16)! An exciting course with an amazing lineup of lecturers in a beautiful location www.mbl.edu/education/ad...

I tracked every keyword in 22 years of Cosyne abstracts to map how computational neuroscience evolved — from Bayesian brains to neural manifolds to LLMs — and where it's heading next.

22 years of Brain Science: what CoSyNe tells us about the evolution of Neuroscience

Tracking the intellectual DNA of Computational and Systems Neuroscience through its flagship meeting

open.substack.com