Now out in @natcomms.nature.com w/ @evfedorenko.bsky.social: across many people (>1k) and tasks (>300), the the brain's language network reliably shows up in the functional connectome (correlated activity in fMRI). 1/
Colton Casto
@coltoncasto.bsky.social
PhD student at Harvard/MIT interested in neuroscience, language, AI | @kempnerinstitute.bsky.social @mitbcs.bsky.social | previously Princeton neuro | coltoncasto.github.io
Hello world! 👋 We’re Minds, Machines, and Brains (MMB) 👤🤖🧠 a new open access journal from @mitpress.bsky.social exploring the principles of intelligence and cognition across natural and artificial minds. Submissions open this Fall! 🔗 direct.mit.edu/mmb
Minds, Machines, and Brains | MIT Press
direct.mit.edu
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
🚨 New Preprint! 🧠 We gave an AI model one simple rule: rearrange your neurons so that nearby ones respond alike. We never told it what a face, a voice, or a sentence was. It grew brain-like maps for all three anyway. 🧵👇 🌐 Website: topo-omni.epfl.ch
New preprint as my first post! "Monosynaptic connections link functionally similar regions in human cortex." We use electrical stimulation + fMRI in epilepsy patients to map whole-brain monosynaptic connectivity at 42 cortical sites. doi.org/10.64898/202... 1/n
I always assumed that brain function had to line up with cytoarchitectonics. It turns out I was wrong. Human cortex, especially PFC, is tiled by chains of functional patches that subdivide and interlink architectonic areas into parallel processing streams. www.biorxiv.org/content/10.6...
Our new paper on brain networks engaged during imagining is out now in Neuron! Here is a download link (free for 50 days): authors.elsevier.com/c/1msNE3BtfH... Congratulations to Nate Anderson for leading this work @rementurus.bsky.social 🧵
🚨 🧠 We have a new preprint out where we studied which brain networks are engaged during mental imagery and self-generated thought. We used a precision fMRI approach along with multidimensional experience sampling (mDES) to get trialwise self-reports from each participant about what they imagined.
Excited to announce a new paper from our lab, by Ian Griffith @iangriffith.bsky.social with help from Preston Hess @phess2.bsky.social, introducing a model of attentional selection. www.nature.com/articles/s41... @mitbcs.bsky.social @mitscience.bsky.social Here is a summary. (1/n)
Optimized feature gains explain and predict successes and failures of human selective listening - Nature Human Behaviour
Griffith et al. show that human-like auditory attentional strategies naturally arise from the optimization of feature gains for selective listening.
nature.com
Is spatial navigation innate 🧠? Using #NeuroPixels we show that the #torus 🍩 underlying the #GridCell map exists already on day 10 in rats — before pups open eyes and ears and before they start upright walking. 🧵1:4 👇 www.biorxiv.org/content/10.6...
biorxiv.org
Really great work demonstrating the importance of task-based responses in characterizing the functional organization of the brain. Congrats to @carobellum.bsky.social and the rest of the team!
🧠 Resting-state fMRI is often treated as the gold standard for studying the brain’s intrinsic organization. But is it actually the best way to estimate functional architecture? We tested this directly. 🧵1/8
I am totally pumped about this new work . "Task-trained RNNs" are a powerful and influential framework in neuroscience, but have lacked a firm theoretical footing. This work provides one, and makes direct contact with the classical theory of random RNNs: www.biorxiv.org/content/10.6...
Excited to share new work on how the brain makes social inferences from visual input! 🧠👯♂️ (With @lisik.bsky.social , @shariliu.bsky.social, @tianminshu.bsky.social , and Minjae Kim!) www.biorxiv.org/content/10.6...
Language areas in the cerebellar mapped by @coltoncasto.bsky.social: www.thetransmitter.org/language/cer... Very consistent with @carobellum.bsky.social functional atlas, but providing deeper details. By now the "terra incognita" of the cerebellum isn't so "incognita" anymore!
Cerebellum responds to language like cortical areas
One of four language-responsive cerebellar regions may encode meaningful information, much like the cortical language network in the left hemisphere, according to a new study.
thetransmitter.org
So great to chat with @thetransmitter.bsky.social about our findings :)
A region in the cerebellum is language-selective—something previously found only in the cortex, a new study suggests. By @natmesanash.bsky.social #neuroskyence www.thetransmitter.org/language/cer...
How do diverse context structures reshape representations in LLMs? In our new work, we explore this via representational straightening. We found LLMs are like a Swiss Army knife: they select different computational mechanisms reflected in different representational structures. 1/
Thanks to @kempnerinstitute.bsky.social for highlighting our new study! I'm excited to see where this research will take us in the years to come :)
New in Neuron! A team including #KempnerInstitute’s @coltoncasto.bsky.social & @gretatuckute.bsky.social maps the cerebellum's role beyond motor control as part of an extended language network.🧠🗣️ More here: bit.ly/4rptQ13 #neuroscience #fMRI @gsas.harvard.edu @evfedorenko.bsky.social
"The cerebellar components of the human language network" www.cell.com/neuron/fullt... @coltoncasto.bsky.social, Evelina Fedorenko & colleagues @cp-neuron.bsky.social
Could not be more excited about Colton's @coltoncasto.bsky.social work! A deep dive into the linguistic cerebellum, and a discovery of an area remarkably functionally similar to the core left-hemisphere language areas, including in its selectivity for language. Go Colton and team!
The cerebellum supports high-level language?? Now out in @cp-neuron.bsky.social, we systematically examined language-responsive areas of the cerebellum using precision fMRI and identified a *cerebellar satellite* of the neocortical language network! authors.elsevier.com/a/1mUU83BtfH... 1/n 🧵👇
The cerebellum supports high-level language?? Now out in @cp-neuron.bsky.social, we systematically examined language-responsive areas of the cerebellum using precision fMRI and identified a *cerebellar satellite* of the neocortical language network! authors.elsevier.com/a/1mUU83BtfH... 1/n 🧵👇
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.
Why isn’t modern AI built around principles from cognitive science or neuroscience? Starting a substack (infinitefaculty.substack.com/p/why-isnt-m...) by writing down my thoughts on that question: as part of a first series of posts giving my current thoughts on the relation between these fields. 1/3
Why isn’t modern AI built around principles from cognitive science?
First post in a series on cognitive science and AI
infinitefaculty.substack.com
New preprint on prosody in the brain! tinyurl.com/2ndswjwu HeeSoKim NiharikaJhingan SaraSwords @hopekean.bsky.social @coltoncasto.bsky.social JenniferCole @evfedorenko.bsky.social Prosody areas are distinct from pitch, speech, and multiple-demand areas, and partly overlap with lang+social areas→🧵
A distinct set of brain areas process prosody--the melody of speech
Human speech carries information beyond the words themselves: pitch, loudness, duration, and pauses--jointly referred to as 'prosody'--emphasize critical words, help group words into phrases, and conv...
tinyurl.com
A left frontal-temporal network selectively supports language comprehension and production. Are computations in this language network driven primarily by bottom-up input, or by top-down task demands? 🧵👇 www.biorxiv.org/content/10.6...
The language network responds robustly to sentences across diverse tasks
A network of left frontal and temporal brain areas supports language comprehension and production, implementing computations related to word retrieval and combinatorial linguistic processing. Here, we...
biorxiv.org
Neuroscience of language has a dilemma: how do we reconcile extensive patient and imaging evidence for **language-specific** processing with the fact that naturalistic language evokes extensive activity all over the brain? We propose a framework that accounts for both.
What does it mean to understand language? We argue that the brain’s core language system is limited, and that *deeply* understanding language requires EXPORTING info to other brain regions. w/ @neuranna.bsky.social @evfedorenko.bsky.social @nancykanwisher.bsky.social arxiv.org/abs/2511.19757 1/n🧵👇
What does it mean to understand language? We argue that the brain’s core language system is limited, and that *deeply* understanding language requires EXPORTING info to other brain regions. w/ @neuranna.bsky.social @evfedorenko.bsky.social @nancykanwisher.bsky.social arxiv.org/abs/2511.19757 1/n🧵👇
What does it mean to understand language?
Language understanding entails not just extracting the surface-level meaning of the linguistic input, but constructing rich mental models of the situation it describes. Here we propose that because pr...
arxiv.org
New paper with @rjantonello.bsky.social @csinva.bsky.social, Suna Guo, Gavin Mischler, Jianfeng Gao, & Nima Mesgarani: We use LLMs to generate VERY interpretable embeddings where each dimension corresponds to a scientific theory, & then use these embeddings to predict fMRI and ECoG. It WORKS!
Evaluating scientific theories as predictive models in language neuroscience https://www.biorxiv.org/content/10.1101/2025.08.12.669958v1
🚨 New Preprint 🚨 Targeting intracranial electrical stimulation (ES) to network regions defined within individuals causes network-level effects By Cyr et al. *** Q: Can we use individualized network maps from precision fMRI to modulate a targeted network via intracranial ES? A: Yes! 🧵:
New paper with @mujianing.bsky.social & @prestonlab.bsky.social! We propose a simple model for human memory of narratives: we uniformly sample incoming information at a constant rate. This explains behavioral data much better than variable-rate sampling triggered by event segmentation or surprisal.
Efficient uniform sampling explains non-uniform memory of narrative stories https://www.biorxiv.org/content/10.1101/2025.07.31.667952v1
Super excited to share our new article: “Dissociable cortical regions represent things and stuff in the human brain” with @nancykanwisher.bsky.social, @rtpramod.bsky.social and @joshtenenbaum.bsky.social Video abstract: www.youtube.com/watch?v=B0XR... Paper: authors.elsevier.com/a/1lWxv3QW8S...
Things and Stuff: How the brain distinguishes oozing fluids from solid objects
YouTube video by McGovern Institute
youtube.com