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Jennifer Hu

@jennhu.bsky.social
2.7K followers 189 following 60 posts

Asst Prof at Johns Hopkins Cognitive Science • Director of the Group for Language and Intelligence (glint) ✨• Interested in all things language, cognition, and AI jennhu.github.io

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Reposted by Jennifer Hu
Tom McCoy @rtommccoy.bsky.social · 01/09/2026
🤖🧠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
Overview of the paper. 
Title: The Emergent Symbolic Structure of Artificial Neural Networks
Authors: Tom McCoy, Paul Soulos, Tal Linzen, Paul Smolensky
Left: Neural networks encode information in vectors (there is then an image of a vector), yet they excel at tasks long thought to require symbolic structure (there is then an image of a symbolic representation, specifically a syntax tree). How do LLMs do it?
Right: We find that LLM representations can be closely approximated with symbolic structures. This approximation lets us edit the structure of an LLM’s output by editing the structure of its internal representations, as shown. There is then an image of two edits to LLMs. In the first one, the original input is 3 + 6 * 8, with an answer of 51. But if we swap the positions of the 3 and the 6, the output becomes 30. In the second one, the original input is a Python command repeating the list [Z, U] three times, producing [Z, U, Z, U, Z, U]. But if we edit the input in a way that adds a Q at the end of the input, the output becomes [Z, U, Q, Z, U, Q, Z, U, Q].
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Reposted by Jennifer Hu
Minds, Machines, and Brains (MMB) @mmb-journal.bsky.social · 02/08/2026
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
direct.mit.edu
Minds, Machines, and Brains | MIT Press
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Reposted by Jennifer Hu
Kyle Mahowald @kmahowald.bsky.social · 02/07/2026
The full BBS treatment from me and @futrell.bsky.social on "How linguistics learned to stop worrying and love the LMs" is now out, with all the commentaries and our response. If you "Save PDF", it will give you the whole target article + commentary + response pdf: www.cambridge.org/core/journal...
cambridge.org
How linguistics learned to stop worrying and love the language models | Behavioral and Brain Sciences | Cambridge Core
How linguistics learned to stop worrying and love the language models - Volume 49
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Jennifer Hu @jennhu.bsky.social · 02/07/2026
What's more nonsensical: smashing a pumpkin using a number, or growing flowers inside a sneeze? Our paper on graded inconceivability is out now in Cognition! Come for the cognitive science 🧠🔍, stay for the whimsy 🌼🧚! 🔗Journal link: bit.ly/gradedInconCog
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Jennifer Hu @jennhu.bsky.social · 01/07/2026
Sadly won't be at ACL in person, but check out our presentations below! 🌟 I'm giving a (remote) keynote at SCiL on 7/4! 🌟We also have a poster on probability x grammaticality, and a talk on pragmatics x Theory of Mind! Our lab is actively recruiting, so please reach out! Details at glintlab.org ✨
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Reposted by Jennifer Hu
Mike Frank @mcxfrank.bsky.social · 27/04/2026
For a year and a half, @carorowland.bsky.social, @lehersingh.bsky.social, Marisa Casillas, Shanley Allen, and I have been meeting to discuss whether innateness is still a useful concept to think about in studying language acquisition. Here's our take: osf.io/preprints/ps...
Title pageThe origins of language have been a persistent object of philosophical and scientific inquiry, in part
because they offer a window into the origins of thought. Classic innatist theories of language have argued
that languages share universal elements that arise because language acquisition is guided by rich,
biologically specified structures in the form of a universal grammar. However, different versions of this
hypothesis that posit substantial amounts of innate content are not consistent with recent evidence. We
review new evidence from language diversity, human interaction, and large language models (LLMs), all
of which challenge classical innatist views. Yet we believe there is still value in asking what elements of
language development are innate. In this Perspective, we integrate evidence from these three areas
towards a broader conception of innateness, one that seeks to explain both consistency and variation in
language acquisition. On this view, innateness remains a key orienting principle for understanding the
origins of language.
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Reposted by Jennifer Hu
Michael Lepori @michael-lepori.bsky.social · 26/02/2026
I'm excited to share that this paper was accepted at ICLR 2026! We show that language models encode one of the most basic ingredients of a world model: the ability to distinguish plausible from implausible states. Check out the paper for more details! See you in Rio! Paper: arxiv.org/abs/2507.12553
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Jennifer Hu @jennhu.bsky.social · 12/02/2026
I wrote a short article on AI Model Evaluation for the Open Encyclopedia of Cognitive Science 📕👇 Hope this is helpful for anyone who wants a super broad, beginner-friendly intro to the topic! Thanks @mcxfrank.bsky.social and @asifamajid.bsky.social for this amazing initiative!
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Reposted by Jennifer Hu
Sam Gershman @gershbrain.bsky.social · 09/01/2026
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.
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Reposted by Jennifer Hu
Mick Bonner @mickbonner.bsky.social · 12/12/2025
Hopkins Cog Sci is hiring! We have two open faculty positions: one in vision, and one language. Please repost!
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Jennifer Hu @jennhu.bsky.social · 11/11/2025
Yeah exactly -- @kanishka.bsky.social in examples like yours above, if we assume that g=1 and those strings aren't likely to be ungrammatical realizations of some other messages, then diffs in p(string) will reflect diffs in p(m). Which is what we want, no?
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Jennifer Hu @jennhu.bsky.social · 10/11/2025
This work was done with an amazing team: @wegotlieb.bsky.social, @siyuansong.bsky.social, @kmahowald.bsky.social, @rplevy.bsky.social Preprint (pre-TACL version): arxiv.org/abs/2510.16227 10/10
Screenshot of paper title and list of authors. The title of the paper is: "What Can String Probability Tell Us About Grammaticality?" The authors are: Jennifer Hu, Ethan Gotlieb Wilcox, Siyuan Song, Kyle Mahowald, and Roger P. Levy.
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Jennifer Hu @jennhu.bsky.social · 10/11/2025
Our work also raises new Qs. If LMs virtually always produce grammatical strings, then why is there so much overlap between the probs assigned to grammatical/ungrammatical strings? This connects to tensions btwn language generation/identification (e.g., openreview.net/forum?id=FGT...) 9/10
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Jennifer Hu @jennhu.bsky.social · 10/11/2025
An offshoot of our analysis: if you use minimal pairs that are not tightly controlled, you risk underestimating the grammatical competence of models, due to differences in underlying message probabilities. 8/10
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Jennifer Hu @jennhu.bsky.social · 10/11/2025
As mentioned above, Prediction #3 shows that recent criticism about the overlap in probabilities across gram/ungram strings should NOT be interpreted as a failure of probability to tell us about grammaticality. This overlap is to be expected if prob is influenced by factors other than gram. 7/10
Screenshot of a figure with two panels, labeled (a) and (b). The caption reads: "Figure 4: Evaluation of Prediction 3. (a) Distributions of scores are highly overlapping across grammatical and ungrammatical sentences (pooled across datasets). (b) Poor separability (area under receiver operating characteristic curve, or AUC) achieved by each model and probability transformation. Horizontal line at 0.5 indicates no separation. For dataset-specific results, see Section B, Figures 5 and 7."
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Jennifer Hu @jennhu.bsky.social · 10/11/2025
We use our framework to derive 3 predictions, which we validate empirically: 1. Correlation btwn the prob of string probs within minimal pairs 2. Correlation btwn LMs’ and humans’ deltas within minimal pairs 3. Poor separation btwn prob of unpaired grammatical and ungrammatical strings 6/10
Screenshot of a figure with two panels, labeled (a) and (b). The caption reads: "Figure 2: (a) Prediction 1a: Logprobs of paired grammatical (x-axis) and ungrammatical (y-axis) sentences are correlated. Dashed line: x = y. (b) Prediction 1b: Correlation between grammatical and ungrammatical logprobs (y-axis) generally decreases as within-pair cosine distance (x-axis) increases."
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Jennifer Hu @jennhu.bsky.social · 10/11/2025
In other words, when messages aren’t controlled for, gram strings won't always be more probable than ungram strings. This phenomenon has previously been used to argue that probability is a bad tool for measuring grammatical knowledge -- but in fact, it follows directly from our framework! 5/10
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Jennifer Hu @jennhu.bsky.social · 10/11/2025
Minimal pairs are pairs of strings with the same underlying m but different values of g. Good LMs have low P(g=0), so they prefer the grammatical string in the minimal pair. But for non-minimal string pairs with different underlying messages, differences in P(m) can overwhelm even good LMs. 4/10
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Jennifer Hu @jennhu.bsky.social · 10/11/2025
Returning to first principles: In our framework, the probability of a string comes from two latent variables: m, the message to be conveyed; and g, whether the message is realized grammatically. Ungrammatical strings get probability mass when g=0: the message is not realized grammatically. 3/10
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Jennifer Hu @jennhu.bsky.social · 10/11/2025
Here we develop and give evidence for a formal framework that reconciles these two observations. Our framework provides theoretical justification for the widespread practice of using *minimal pairs* to test what grammatical generalizations LMs have acquired. 2/10
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Jennifer Hu @jennhu.bsky.social · 10/11/2025
New work to appear @ TACL! Language models (LMs) are remarkably good at generating novel well-formed sentences, leading to claims that they have mastered grammar. Yet they often assign higher probability to ungrammatical strings than to grammatical strings. How can both things be true? 🧵👇
Screenshot of a figure with two panels, labeled (a) and (b). The caption reads: "Figure 1: (a) Illustration of messages (left) and strings (right) in toy domain. Blue = grammatical strings. Red = ungrammatical strings. (b) Surprisal (negative log probability) assigned to toy strings by GPT-2."
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Reposted by Jennifer Hu
Tomer Ullman @tomerullman.bsky.social · 06/11/2025
It’s grad school application season, and I wanted to give some public advice. Caveats: -*-*-*-* 
> These are my opinions, based on my experiences, they are not secret tricks or guarantees 
> They are general guidelines, not meant to cover a host of idiosyncrasies and special cases
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Jennifer Hu @jennhu.bsky.social · 04/11/2025
Interested in doing a PhD at the intersection of human and machine cognition? ✨ I'm recruiting students for Fall 2026! ✨ Topics of interest include pragmatics, metacognition, reasoning, & interpretability (in humans and AI). Check out JHU's mentoring program (due 11/15) for help with your SoP 👇
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Reposted by Jennifer Hu
Tomer Ullman @tomerullman.bsky.social · 14/10/2025
New preprint! "Non-commitment in mental imagery is distinct from perceptual inattention, and supports hierarchical scene construction" (by Li, Hammond, & me) link: doi.org/10.31234/osf... -- the title's a bit of a mouthful, but the nice thing is that it's a pretty decent summary
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Jennifer Hu @jennhu.bsky.social · 07/10/2025
At #COLM2025 and would love to chat all things cogsci, LMs, & interpretability 🍁🥯 I'm also recruiting! 👉 I'm presenting at two workshops (PragLM, Visions) on Fri 👉 Also check out "Language Models Fail to Introspect About Their Knowledge of Language" (presented by @siyuansong.bsky.social Tue 11-1)
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Jennifer Hu @jennhu.bsky.social · 26/08/2025
Can AI models introspect? What does introspection even mean for AI? We revisit a recent proposal by Comșa & Shanahan, and provide new experiments + an alternate definition of introspection. Check out this new work w/ @siyuansong.bsky.social, @harveylederman.bsky.social, & @kmahowald.bsky.social 👇
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Jennifer Hu @jennhu.bsky.social · 22/08/2025
Due to popular demand, we are extending the CogInterp submission deadline again! 🗓️🥳 Submit by *8/27* (midnight AoE)
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Jennifer Hu @jennhu.bsky.social · 14/08/2025
🗓️ The submission deadline for CogInterp @ NeurIPS has officially been *extended* to 8/22 (AoE)! 👇 Looking forward to seeing your submissions!
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Jennifer Hu @jennhu.bsky.social · 28/07/2025
Heading to CogSci this week! ✈️ Find me giving talks on: 💬 Prod-comp asymmetry in children and LMs (Thu 7/31) 💬 How people make sense of nonsense (Sat 8/2) 📣 Also, I’m recruiting grad students + postdocs for my new lab at Hopkins! 📣 If you’re interested in language / cognition / AI, let’s chat! 😄
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Jennifer Hu @jennhu.bsky.social · 16/07/2025
Join us at NeurIPS in San Diego this December for talks by experts in the field, including James McClelland, @cgpotts.bsky.social, @scychan.bsky.social, @ari-holtzman.bsky.social, @mtoneva.bsky.social, & @sydneylevine.bsky.social! 🗓️ Submit your 4-page paper (non-archival) by August 15! 4/4
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Jennifer Hu @jennhu.bsky.social · 16/07/2025
We're bringing together researchers in fields such as machine learning, psychology, linguistics, and neuroscience to discuss new empirical findings + theories which help us interpret high-level cognitive abilities in deep learning models. 3/4
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Jennifer Hu @jennhu.bsky.social · 16/07/2025
Deep learning models (e.g. LLMs) show impressive abilities. But what generalizations have these models acquired? What algorithms underlie model behaviors? And how do these abilities develop? Cognitive science offers a rich body of theories and frameworks which can help answer these questions. 2/4
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Jennifer Hu @jennhu.bsky.social · 16/07/2025
Excited to announce the first workshop on CogInterp: Interpreting Cognition in Deep Learning Models @ NeurIPS 2025! 📣 How can we interpret the algorithms and representations underlying complex behavior in deep learning models? 🌐 coginterp.github.io/neurips2025/ 1/4
coginterp.github.io
Home
First Workshop on Interpreting Cognition in Deep Learning Models (NeurIPS 2025)
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Robert Hawkins @rdhawkins.bsky.social · 28/05/2025
Happy to announce the first workshop on Pragmatic Reasoning in Language Models — PragLM @ COLM 2025! 🎉 How do LLMs engage in pragmatic reasoning, and what core pragmatic capacities remain beyond their reach? 🌐 sites.google.com/berkeley.edu/praglm/ 📅 Submit by June 23rd
sites.google.com
PragLM @ COLM '25
IMPORTANT DATES
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
Preprint link: arxiv.org/abs/2504.14107 A huge thank you to my amazing collaborators Michael Lepori (@michael-lepori.bsky.social) & Michael Franke (@meanwhileina.bsky.social)! (12/12)
arxiv.org
Signatures of human-like processing in Transformer forward passes
Modern AI models are increasingly being used as theoretical tools to study human cognition. One dominant approach is to evaluate whether human-derived measures are predicted by a model's output: that ...
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
Our work also suggests a new way of using AI models to study cognition: not just as a black box mapping stimuli to outputs, but potentially also as processing models. Excited about future work using mechanistic interpretability to make new, testable predictions about human cognition! (11/12)
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
From an AI perspective, our approach could be leveraged to better understand how certain inputs are easier or harder for models to process. This could help AI researchers design evaluations with better construct validity, or more efficient early-exiting methods to save test-time compute. (10/12)
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
Our results suggest that model processing & human processing may be facilitated by similar properties of an input stimulus, and this similarity has emerged through general-purpose objectives like next-token prediction or image recognition. Why does this matter for AI/cogsci? 👇 (9/12)
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
Moreover, across our experiments, larger models do not always show more human-like processing patterns. Interestingly, this seems to generalize prior findings that human reading times are not always predicted better by larger LMs. (8/12)
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
We then test whether measures of forward-pass dynamics (including competitor interference, & others) predict signatures of processing in humans. We find that dynamic measures improve prediction of human measures above static (final-layer) measures -- across models, domains, & modalities. (7/12)
Screenshot of Figure 3, which has two panels, labeled (a) and (b). The caption says the following. Figure 3: Experiment 2 results for text domains. (a) Top: R2 achieved by model processing measures (x-axis) across groups of human DVs (hue). Bottom: Log Bayes Factor comparing critical to baseline regression models. Horizontal line = log(3). (b) Mean R2 across bins of model sizes.
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
First, we use simple mech interp tools to measure competitor interference, such as evidence for “two-stage processing” and the “time to decision”. We find that models indeed appear to initially favor a competing incorrect answer in the cases where we expect decision conflict in humans. (6/12)
Screenshot of Figure 2, which has three panels, labeled (a), (b), and (c). The caption says the following. Figure 2: Experiment 1 results. (a) LMs generally show stronger signs of two-stage processing for the items with competing intuitive answers. Asterisks denote sig. t-tests comparing means across conditions within each domain. (b) ∆LogProb across layers for sample LMs in the capitals recall domain, illustrating different processing strategies. (c) Two-stage processing interacts with size.
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
1. Do models show signs of competitor interference effects? 2. Do measures characterizing (a) competitor interference effects or (b) other aspects of processing difficulty in models predict human processing load? 3. How does model size affect the similarity between model vs human processing? (5/12)
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
One phenomenon in human processing is competitor interference: conflict btwn a salient (but incorrect) answer and a correct answer. We use this as a hypothesis-driven case study to look at the relationship btwn human/machine processing, before broadening our investigation. We explore 3 RQs👇 (4/12)
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
Meanwhile, mechanistic interpretability is starting to reveal the “pipelines” that models use to perform high-level cognitive tasks. So we ask: Do models & humans use similar processing pipelines? (3/12)
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
Many studies treat AI models as black boxes mapping inputs to outputs, and compare output quantities (eg logprobs) to human behavior (eg offline judgments, reading times). This is often theoretically motivated: eg, using LMs to test the role of prediction in reading, or probability & grammar. (2/12)
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Jennifer Hu @jennhu.bsky.social · 20/05/2025
Excited to share a new preprint w/ @michael-lepori.bsky.social & Michael Franke! A dominant approach in AI/cogsci uses *outputs* from AI models (eg logprobs) to predict human behavior. But how does model *processing* (across layers in a forward pass) relate to human real-time processing? 👇 (1/12)
Screenshot of Figure 1, which has two panels labeled (a) and (b). The caption states the following. Figure 1: Overview of our study. (a) Experiment 1: We explore whether forward passes show mechanistic signatures of competitor interference, first preferring a salient competing intuitive answer before preferring the correct answer. (b) Experiment 2: We systematically investigate the ability of dynamic measures derived from forward passes to predict indicators of processing load in humans.
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Jennifer Hu @jennhu.bsky.social · 13/03/2025
Ahh thank you Lucy!! 😊❤️
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Jennifer Hu @jennhu.bsky.social · 12/03/2025
Check out our new work on introspection in LLMs! 🔍 TL;DR we find no evidence that LLMs have privileged access to their own knowledge. Beyond the study of LLM introspection, our findings inform an ongoing debate in linguistics research: prompting (eg grammaticality judgments) =/= prob measurement!
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Tomer Ullman @tomerullman.bsky.social · 06/03/2025
new preprint on Theory of Mind in LLMs, a topic I know a lot of people care about (I care. I'm part of people): "Re-evaluating Theory of Mind evaluation in large language models" (by Hu* @jennhu.bsky.social , Sosa, and me) link: arxiv.org/pdf/2502.21098
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Mike Frank @mcxfrank.bsky.social · 06/03/2025
AI models are fascinating, impressive, and sometimes problematic. But what can they tell us about the human mind? In a new review paper, @noahdgoodman.bsky.social and I discuss how modern AI can be used for cognitive modeling: osf.io/preprints/ps...
Figure 1. A schematic depiction of a model-mechanism mapping between a human learning system (left side) and a cognitive model (right side). Candidate model mechanism mappings are pictured as mapping between representations but also can be in terms of input data, architecture, or learning objective.Figure 2. Data efficiency in human learning. (left) Order of magnitude of LLM vs. human training data, plotted by human age. Ranges are approximated from Frank (2023a). (right) A schematic depiction of evaluation scaling curves for human learners vs. models plotted by training data
quantity.Paper abstract
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