I'm excited to announce that I had my first (co-authored) book published today! "The Rational Use of Cognitive Resources" with Falk Lieder and Tom Griffiths (@cocoscilab.bsky.social ). You can read it for free! (see thread)

Hybrid neural–cognitive models reveal how memory shapes human reward learning

Convincing evidence that people recall individual past experiences to inform decisions—specifically when an easier incremental learning strategy isn’t available. Also, a masterclass in experimental design.

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.

Writing is thinking Outsourcing the entire task of writing to LLMs will deprive us of the essential creative task of interpreting our findings and generating a deeper theoretical understanding of the world.

How do we achieve few-shot generalization? New work led by @fabianrenz.bsky.social dives into the role of replay in learning and using structure to generalize reward. Dream team effort with Shany Grossman @nathanieldaw.bsky.social Peter Dayan & @doellerlab.bsky.social www.biorxiv.org/content/10.6...

Now out in JEP: General, "How working memory and reinforcement learning interact when avoiding punishment and pursuing reward concurrently" psycnet.apa.org/record/2026-... Preprint with final version: osf.io/preprints/ps... 1/n

We're excited to announce that Cognitive Science at Dartmouth is recruiting PhD students to work collaboratively with me, Steven Frankland, and Fred Callaway. Come study the principles and mechanisms that enable us to understand, plan, and act in the world! Info: sites.dartmouth.edu/cogscigrad/

Yes! @upenn.edu declines signing The Compact. I'm proud of this decision.

1st Sharp Lab preprint! 🚨 We tested how anxiety affects task generalization—not how people generalize threat stimuli, but how they reuse action-outcome structures when planning in new contexts. Worry makes people avoid reusing actions that co-occurred w/ threat! 📄: osf.io/preprints/ps... 🧵 1/12

Forget modeling every belief and goal! What if we represented people as following simple scripts instead (i.e "cross the crosswalk")? Our new paper shows AI which models others’ minds as Python code 💻 can quickly and accurately predict human behavior! shorturl.at/siUYI%F0%9F%...

New in @pnas.org: doi.org/10.1073/pnas... We study how humans explore a 61-state environment with a stochastic region that mimics a “noisy-TV.” Results: Participants keep exploring the stochastic part even when it’s unhelpful, and novelty-seeking best explains this behavior. #cogsci #neuroskyence

We often hear from reviewers: "what about demand effects?" So we developed a method to eliminate them. Something weird happened during testing: We couldn’t detect demand effects in the first place! (1/8)

Happy to share "The Dynamics of Caregiver Unpredictability Shape Moment-to-Moment Infant Looking During Dyadic Interaction," out now in Child Development thanks to a large team of people I worked on this with! srcd.onlinelibrary.wiley.com/doi/pdfdirec...

Our new paper is out in PNAS: "Evolving general cooperation with a Bayesian theory of mind"! Humans are the ultimate cooperators. We coordinate on a scale and scope no other species (nor AI) can match. What makes this possible? 🧵 www.pnas.org/doi/10.1073/...

Centaur's performance may be largely driven by learning a good model of behavioral auto-regression—independent of the task. An important lesson for cognitive modelers: higher likelihood ≠ better account of behavior. osf.io/preprints/ps...

preprint alert 🚨 1/ Can we accurately detect sequential replay in humans using Temporally Delayed Linear Modelling (#TDLM)? In our recent study, we could not find any replay and decided to dig deeper by running a hybrid simulation with surprising results. Link to preprint & details below 👇

Our study is out in Nature! Using wireless Neuropixels we recorded hippocampal activity in freely flying bats and uncovered replay and theta(less) sweeps, revealing striking differences from classic rodent models. 👉 www.nature.com/articles/s41...

I asked ChatGPT to respond to this critique. It replies: "That’s a sharp observation—and honestly, a fair one. ChatGPT can sound overly agreeable or eager to please, much like..."

Stop spreading this garbage about em dashes in ACTUAL EDITED PROSE OH MY GOD. Plenty of actual human beings know how to type em dashes! We’re called “writers” and “editors” — maybe you’ve heard of us?

After all these reports of authors adding language instructions for LLM reviews in their papers I wanted to check this myself and I downloaded the .tex source from one of these papers. Here is an example. (I will not share the identity of the paper)

Evidence for model-based meta-control? I look forward to reading!

🔥Hot Take: When you quote the middle of a sentence at the end of your sentence, the period should be *after* the quote, as in "the middle of a sentence". Don't put your punctuation in my mouth.

Super excited for this conference on mental health and adaptation to uncertainty. Remarkable how the organizers built a speaker lineup that is so interdisciplinary and yet so thematically focused. And the location certainly doesn't hurt... www.fens.org/news-activit...

Tukey xkcd.com/3104/

Our latest @cccr.bsky.social survey reveals how unpopular the president’s most notable policy changes are with the American public. The survey also highlights the diversity of views within the GOP, related to their information diets, as well as US economic attitudes. cccr.wisc.edu/wp-content/u...

Compelling and thorough evidence for a very cool idea. Awesome paper.

I'm thrilled to announce that I will start as an Assistant Professor in Psychology & Cognitive Science at the University of Arizona in Jan 2026! My lab will investigate human planning and decision making through a combination of computational models, behavior, and fMRI (1/2)

📢 I'm happy to share the preprint: _Reward-Aware Proto-Representations in Reinforcement Learning_ ‼️ My PhD student, Hon Tik Tse, led this work, and my MSc student, Siddarth Chandrasekar, assisted us. arxiv.org/abs/2505.16217 Basically, it's the SR with rewards. See below 👇

the functional form of moral judgment is (sometimes) the nash bargaining solution new preprint👇

Because we must build good things while we scream about the bad, I have started a "Data for Good" team @data-for-good-team.bsky.social that partners with organizations needing short-term data science help. We have three projects ongoing & will add more as our capacity grows. data-for-good-team.org

Despite the world being on fire, I can't help but be thrilled to announce that I'll be starting as an Assistant Professor in the Cognitive Science Program at Dartmouth in Fall '26. I'll be recruiting grad students this upcoming cycle—get in touch if you're interested!

🤔 Interested in models of social interaction and computational psychiatry? 🤗 If so, @shawnrhoadsphd.bsky.social and I are seeking a highly motivated and talented postdoc to work on these topics! Please share widely! apply.interfolio.com/165809

Episodic memory facilitates flexible decision making via access to detailed events https://www.biorxiv.org/content/10.1101/2025.03.13.643066v1

In the latest assault on First Amendment rights, Columbia University has expelled and fired Grant Miner, President of UAW Local 2710, which represents thousands of Columbia student workers. The firing comes one day before contract negotiations were set to open with the University.

Chat GPT just spontaneously made a fairly solid joke. I was asking it for help with a stuck cable and accidentally sent just "Ω". It then replies: Looks like you might be dealing with some resistance—both literally and figuratively. Need more help with that stuck Ethernet cable? 😆

when the paper you're reviewing put the figures at the end

this this this 100%. a few days ago, i allowed myself to NOT look at screens & emails as soon as i woke up. instead, i lay in bed, half asleep, & thought for a while. and i worked out a solution to a problem. forget fear: EMAIL is the mind killer, the little-death that brings total obliteration.

I feel super lucky to have been part of this project showing how people selectively simulate actions whose value is more uncertain. To highlight one result, Haoxue shows that people preferentially simulate actions that lead to a greater number of possible future states.

🚨In Science🚨 Conspiracy beliefs famously resist correction, ya? WRONG: We show brief convos w GPT4 reduce conspiracy beliefs by ~20%! -Lasts over 2mo -Works on entrenched beliefs -Tailored AI response rebuts specific evidence offered by believers www.science.org/doi/10.1126/... 1/ [X->BSky repost]

I feel like a lot of the LLM haters have a romanticized view of human intelligence. How do you think you learned math besides by reading/listening to books/lectures and then trying to answer questions well enough to get reward?

Zotero's link preview has gotten incredible recently. Hovering over most figure/equation/citation references shows a pop up of the relevant part of the pdf (or even a formatted, clickable list of references)—even in papers from the 50s!

My paper on hierarchical plans is out in Cognition!🎉 tldr: We ask participants to generate hierarchical plans in a programming game. People prefer to reuse beyond what standard accounts predict, which we formalize as induction of a grammar over actions. authors.elsevier.com/a/1kBQr2Hx2x...

I don’t understand how Tomer finds time for these nuggets of investigative journalism, but gosh am I glad he does.

the rapid transition of academics off x (despite temporarily reducing reach/followers) makes you wonder what’s stopping us from ending the for-profit, closed access publishing industry. it’s, like…. we can just do it? or if not, interesting to consider what the inertial differences are.

🚨 Clinicians have noted for decades how planning & anxiety are linked. Yet, computational psychiatry thus far failed to show how. Here, I explain that we need to broaden how we model planning to reveal its *biases* in chronic anxiety. A 🧵 on the framework 1/n authors.elsevier.com/a/1kAJC4sIRv...

As a field, can we please stop interpreting statistical insignificance as evidence that an effect doesn’t exist? Pretty please?? Like, with a cherry and everything??? #PsychSciSky

Excited to announce that I'll be starting a lab at the University of Montreal (psychology) and Mila (Montreal Institute of Learning Algorithms) starting summer 2025. More info to come soon, but I'll be recruiting at the Masters and PhD levels. Please share / get in touch if you're interested!

This book has been a *long* time in the making, and the effort shows. I hope I one day have the opportunity to teach a class based on it.