Postdoc in the Hayden lab at Baylor College of Medicine studying neural computations of natural language & communication in humans. Sister to someone with autism. F32 NIDCD Fellow | Autism Research Institute funded | Simons F2F | she/her. melissafranch.com
I’m excited to share my newest work with @benhayden.bsky.social, and the work I’m most proud of to date, on characterizing semantic coding in single-neuron hippocampal activity in patients with autism during natural language comprehension!
www.biorxiv.org/content/10.6...
Mass production has hit mathematics. Science is next.
Back in July this article made some predictions for how AI will transform science research. So far, it seems about on track.
www.thetransmitter.org/artificial-i...
Neuron continues its three-part series on neuroscience and AI with “Neuroscience and AI: Emerging Synergies”.
Explore how brains and AI are converging, from language models and scientific discovery to more brain-like AI systems.
The synergy deepens.
www.cell.com/neuron/issue...
To understand the brain, we need to study groups of neurons, not individual cells alone. These groups form distinct “subspaces,” allowing different downstream areas to extract the information they need.
Beyond single-cell sensory representations in cortex
doi.org/10.1016/j.co...#neuroscience
New paper from the Neurosurgery research team at BCM! 🧵
"A population code for semantics in human hippocampus"
led by Melissa Franch. We recorded hippocampus single neurons while people listened to podcasts.
www.nature.com/articles/s41...
Excited to see this work published! We find that the brain codes semantic relationships similar to contextual LLMs (like GPT2) but unlike LLMs, uses contrastive coding to prevent confusion of highly similar words. Many thanks to the reviewers and BCM neurosurgery team! www.nature.com/articles/s41...
I am incredibly proud to share my first, first-author paper as a postdoc with @benhayden.bsky.social . How does the human hippocampus, known for encoding concepts, represent the meanings of words while listening to narrative speech?
www.biorxiv.org/content/10.1...
New work out today!
The result of a 15 year project to offer genuine linking hypotheses between linguistics and neuroscience: a revised research program, and its first result - a novel neural binding operation ('Meld') capturing core properties of natural language syntax 🧵
arxiv.org/abs/2609.14384
Our review on superposition in AI & brains is published in
@nature.com#Machine#Intelligence 🌐
Neural networks encode concepts in superposition. We can recover them in 3 steps: identifiability, compressed sensing, interpretability.
W/ @david-klindt.bsky.social O'Neil Reizinger & Maurer 🌟
The Grand Plan for brain & mind research is in terrific hands with the researchers at Baylor College of Medicine!
From an excellent panel discussion across silos to many insightful conversations with PIs and trainees, I'm a bit blown away by what they are up to here. Impactful & exciting.
And in some patients we measured gaze as well. We find that gaze has its own maps, and those are also semi-orthogonalized. So in debates about whether primate hippocampus does gaze or place, the answer is “both, and their codes are rotated”.
Autism has long been linked to difficulties with Theory of Mind.
But what exactly is driving these differences? And what happens in the brain?
In our new preprint, we show that adaptive mentalization might be key.
A 🧵 #CogSci#CogNeuroosf.io/preprints/ps...
New preprint! Posterior cingulate is often linked to memory in humans but decisions in monkeys yet there's little consensus about its functional neuroanatomy. We recorded LFPs+single units in humans during matched value and memory based decisions, finding convergence in dorsal, but not ventral, PCC.
The superposition of these two studies — both incredible — reflect a snapshot of "one big thing" systems neuroscience has yet to resolve.
In mice:
1. Task-related signals are everywhere.
2. Absent large swaths of "everywhere," suprisingly sophisticated learning & behavior remains.
Textbook: tracking position during navigation is primarily the job of the hippocampus. Recent findings suggest a more complicated story.
Recording >20k neurons brainwide, we indeed find spatial representations in every region!
With @kenneth-harris.bsky.social and @carandinilab.net
🤖🧠NEW PAPER🧠🤖
(The result of an 8-year project!)
LLMs seem very different from symbolic systems. Yet LLMs excel in symbolic domains (e.g., language/code/math). How do they do it?
Our finding: LLM representations have implicit symbolic structure!
Link in thread ⬇️
1/n
My dept/area is hiring! We're open to animal species/model and research area. UCD is an amazing place to do nonhuman animal work - major 🐒 center, a band new rodent vivarium in the Psych building, and capacity to house all sorts of other animals!
recruit.ucdavis.edu/JPF07812
Check out our new TICS article! We present an alternative take on the widely observed alignment between various AI models and human brain representations: the Umwelt Representation Hypothesis.
First Noel Lab Pre-print!
If you are into "peri-personal space" and feel like we need more single cell recordings, this one is for you!
www.biorxiv.org/content/10.6...
First study out! Using a new cooperative paradigm and multi-agent inverse RL, we show that mice spontaneously adopt leader/follower roles, and the prefrontal cortex encodes these role dynamics and an egocentric social value map of the partner’s position. (1/3)
www.nature.com/articles/s41...
Excited to share our new paper: "Probing the content of semantic representations in body-selective regions"
We propose a framework based on object co-occurrence to interpret semantic representations of natural scenes predicted by LLM embeddings.
doi.org/10.1162/IMAG...
New perspective piece out in @cp-neuron.bsky.social with Zaid Zada, @adelegoldberg.bsky.social, and Uri Hasson! We try to articulate some of our excitement about LLMs and discuss what kinds of insights they might provide into the neural computations supporting natural language in the human brain.
Our latest profile is here! Dr. Lea Duncker (@leaduncker.bsky.social) uses statistical and theoretical approaches to study the neural basis of flexible behavior. Follow the link below to learn more!
#StoriesOfWiN#WomenInNeurosciencewww.storiesofwin.org/profiles/202...
(1/8) Our approach for untangling brain-wide interactions is out today in @cp-neuron.bsky.social!
Current-Based Decomposition (CURBD) uses RNNs constrained by real neural data to reveal the input driving neurons, uncovering how brain regions talk to each other.
doi.org/10.1016/j.ne...
🧵👇
US scientists: Going into fall 26, how are you thinking about things?
Following Fall 24 events and a tumultuous spring 25, I remember a convo with a colleague in which we agreed we just needed to wait things out until fall 25 and we'd have some clarity about the landscape (eg for funding). /1
For a neural circuit to be "specialized", does it need specialized neurons? In our new work - now out in @NatureNeuro - we address this question in the BLA, using representational geometry to propose a new population-centric way of defining circuit specialization. 🧵👇 1/
And on Wednesday afternoon it's time for our Community Event that focuses on what neural encoding models are useful for, where I'll be showcasing several cool projects on EEG encoding during scene perception led by @niklasmuller.bsky.social! 2026.ccneuro.org/community-ev...
Then on Wednesday, double whammy: in the morning I'll present a poster on our hot-of-the-press EEG decoding study on neural representational dynamics between images vs. video, led by @annewzonneveld.bsky.social (Poster C85) openreview.net/forum?id=njG...
This project is one of our greatest undertakings as a lab, with Calli at the helm (in terms of data collection, transcription of speech features during naturalistic dialogue, and computational modeling), and we're excited to get everyone's feedback!
I'm over the moon to be recognized for my future plans in (and lifelong commitment to) autism neuroscience research through earning the Simons Foundation Fellows To Faculty award! I can't wait to dive into this work alongside this community✨🥹
We're pleased to announce the 2026 class of our Fellows-to-Faculty program!
This fellowship supports talented early-career scientists and their research visions as they transition into tenure-track faculty positions in autism and #neuroscience research.
See the new class: https://bit.ly/4yXUjrd
How does your brain register whether something feels good or bad? New research had people listen to stories in an MRI scanner and found the brain maps feelings on a single scale from unpleasant to pleasant, using far more regions than expected.
#Valence, #Naturalistic
Link: doi.org/10.64898/202...
Out today on @nature.com! Connecting neural specialization, population geometry, and their functional implications across the cortical hierarchy. So grateful for this beautiful and fun collaboration with @shuqiw.bsky.social, S Muscinelli, L Paninski, and @stefanofusi.bsky.social!
New paper alert from our lab!
nature.com/articles/s41...
We used stimuli sequences following 1/f statistical patterns—an ubiquitous statistical structure in natural stimuli—to probe predictive processing in the human brain.
How does the brain predict upcoming sensory inputs based on past inputs?
Our new preprint is out!! The human brain runs on ~20 watts. Computers and modern AI systems require vastly higher energy. This gap raises a fundamental question: how does the brain compute so efficiently? In our new study, we take a critical step toward measuring and understanding this directly 1/3
1/11 Happy to share our TICS paper on using the flexibility of one of the most basic cognitive functions, perception, to understand one of the most complex cognitive dysfunctions, psychiatric conditions (also my first formal work in computational psychiatry 🎉)
📄: www.cell.com/trends/cogni...
🧵 : 👇
Congratulations @xinyuanyan.bsky.social! I’m so grateful to do neuroscience with you. Your blog post provides a clear summary of the research and illustrates your strong skills in communicating your science!
For many bilingual people, switching between languages feels effortless. Now, scientists have figured out how bilingual brains accomplish this feat at the single neuron level. spkl.io/633297EUXJ
Xinyuan Yan, Benjamin, Y. Hayden, @sameershethmd.bsky.social & colleagues
@cp-cell.bsky.social
Some neurons like to ride on slow LFP oscillations, regardless of their phase! This might represent a mechanism to coordinate neural activity and propagate information across brain circuits 🧠 amazing collaboration led by the super talented @zahrajourahmad.bsky.social and Andrew Watrous!
Do #neurons show preferential firing at specific oscillatory frequencies? @elebartoli.bsky.social &co use recordings from neurosurgical patients to show that freq of oscillations modulates neuronal firing; implications for freq-targeted #NeuralStimulation@plosbiology.org 🧪 plos.io/44odgVM
Many of the scientific questions we're interested in tackling require studying learning over long periods of time across the brain. This is challenging – which is why we're excited to say we've been developing a system for chronic wireless recording using long Neuropixels probes in macaque monkeys.
When listening to a story, earlier parts of the story (context) and the speaker's gestures help us predict and understand what they are saying. In a new preprint we show context and gestures have a push-pull synergy on neural response to linguistic information 👇🧵
Check out our latest profile! Dr. Megan Peters (@meganakpeters.bsky.social) studies how the brain represents & uses uncertainty and she also co-founded the online summer school, Neuromatch Academy. Learn more at the link below! #WomenInNeuroscience#StoriesOfWiNwww.storiesofwin.org/profiles/202...
Info. processing, memory, adaptive decisions.. none of it fully captures what makes us intelligent *beings* with subjective experience.
@meganakpeters.bsky.social thinks hard about that gap and how to formalize that in theory & expmt. And she somehow found time to co-build @neuromatch.bsky.social 🤩
Check out our latest profile! Dr. Megan Peters (@meganakpeters.bsky.social) studies how the brain represents & uses uncertainty and she also co-founded the online summer school, Neuromatch Academy. Learn more at the link below! #WomenInNeuroscience#StoriesOfWiNwww.storiesofwin.org/profiles/202...