Ryan P. Badman
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ryanpaulbadman1.bsky.social
Ryan P. Badman
@ryanpaulbadman1.bsky.social
Postdoc in Kanaka Rajan laboratory at Harvard Medical Neurobiology & Kempner Institute - Theoretical/Comp Neuro. Background includes comp neuro, social neuro, cultural psychology, biophysics.
Reposted by Ryan P. Badman
We wrote a little #NeuroAI piece about in-context learning & neural dynamics vs. continual learning & plasticity, both mechanisms to flexibly adapt to changing environments:
arxiv.org/abs/2507.02103
We relate this to non-stationary rule learning tasks with rapid performance jumps.

Feedback welcome!
What Neuroscience Can Teach AI About Learning in Continuously Changing Environments
Modern AI models, such as large language models, are usually trained once on a huge corpus of data, potentially fine-tuned for a specific task, and then deployed with fixed parameters. Their training ...
arxiv.org
July 6, 2025 at 10:18 AM
Reposted by Ryan P. Badman
(1/7) New preprint from Rajan lab! 🧠🤖
@ryanpaulbadman1.bsky.social & Riley Simmons-Edler show–through cog sci, neuro & ethology–how an AI agent with fewer ‘neurons’ than an insect can forage, find safety & dodge predators in a virtual world. Here's what we built

Preprint: arxiv.org/pdf/2506.06981
July 2, 2025 at 6:34 PM
Reposted by Ryan P. Badman
Humans and animals can rapidly learn in new environments. What computations support this? We study the mechanisms of in-context reinforcement learning in transformers, and propose how episodic memory can support rapid learning. Work w/ @kanakarajanphd.bsky.social : arxiv.org/abs/2506.19686
From memories to maps: Mechanisms of in context reinforcement learning in transformers
Humans and animals show remarkable learning efficiency, adapting to new environments with minimal experience. This capability is not well captured by standard reinforcement learning algorithms that re...
arxiv.org
June 26, 2025 at 7:01 PM
Reposted by Ryan P. Badman
Pleased to share our ICML Spotlight with @eberleoliver.bsky.social, Thomas McGee, Hamza Giaffar, @taylorwwebb.bsky.social.

Position: We Need An Algorithmic Understanding of Generative AI

What algorithms do LLMs actually learn and use to solve problems?🧵1/n
openreview.net/forum?id=eax...
June 20, 2025 at 3:48 PM
Reposted by Ryan P. Badman
Very proud of @rtpramod.bsky.social and the rest of our team for this lovely work showing that the brain's Physics Network represents object-to-object contact and predicted future events:
June 19, 2025 at 12:14 PM
Reposted by Ryan P. Badman
Our work, out at Cell, shows that the brain’s dopamine signals teach each individual a unique learning trajectory. Collaborative experiment-theory effort, led by Sam Liebana in the lab. The first experiment my lab started just shy of 6y ago & v excited to see it out: www.cell.com/cell/fulltex...
June 11, 2025 at 3:18 PM
Reposted by Ryan P. Badman
For almost a decade, there's been a lot of (justified) hand-wringing and paper-writing about fairness issues in AI. This case gets to the heart of a very important question - how much of that work has materially improved the lives of real people?

Grateful for this careful & honest investigation.
June 11, 2025 at 10:58 PM
Our new preprint from Rajan lab (Harvard):

"Deep RL Needs Deep Behavior Analysis: Exploring Implicit Planning by Model-Free Agents in Open-Ended Environments"

Sophisticated & sometimes insect-like planning, exploration, predator evasion, and foraging strategies by DRL.

arxiv.org/abs/2506.06981
Deep RL Needs Deep Behavior Analysis: Exploring Implicit Planning by Model-Free Agents in Open-Ended Environments
Understanding the behavior of deep reinforcement learning (DRL) agents -- particularly as task and agent sophistication increase -- requires more than simple comparison of reward curves, yet standard ...
arxiv.org
June 10, 2025 at 2:46 PM
A big challenge for comp social neuro is to go to more naturalistic small groups while still doing controlled, goal-oriented experiment & analysis. We present a strong effort in that direction (from RIKEN) showing how humans balance memory, reciprocity, value. w/ fMRI www.biorxiv.org/content/10.1...
January 23, 2024 at 5:18 AM
"We find that all five studied off-the-shelf [military-related] LLMs show forms of escalation and difficult-to-predict escalation patterns.. models tend to develop arms-race dynamics, leading to greater conflict, and in rare cases, even to the deployment of nuclear weapons." arxiv.org/abs/2401.03408
January 13, 2024 at 5:40 PM
"In contrast to past systematic replication efforts.. replication attempts here produced the expected effects with significance testing (P < 0.05) in 86% of attempts... justifies confidence in rigour-enhancing methods to increase the replicability of new discoveries"

www.nature.com/articles/s41...
November 19, 2023 at 5:29 AM
"We show that even in a simple, idealised network model, many mechanistically different plasticity rules are equally compatible with empirical data... Our results suggest the need for a shift in the study of plasticity rules"

www.biorxiv.org/content/10.1...
November 5, 2023 at 11:11 PM
Reposted by Ryan P. Badman
Next we created a nonlinear latent variable model of OFC activity in our task using CEBRA, the awesome new method from @trackingactions.bsky.social' lab, to understand how the task is encoded in the neural circuit at the level of aggregate neural dynamics
October 14, 2023 at 4:06 PM
Reposted by Ryan P. Badman
Absolutely thrilled to share my postdoc work in the Axel lab. We found odor-evoked representations of the intrinsic value of information in mouse orbitofrontal cortex and showed that mice desire knowledge as its own reward. Now on bioRxiv! www.biorxiv.org/content/10.1...
Representations of information value in mouse orbitofrontal cortex during information seeking
bioRxiv - the preprint server for biology, operated by Cold Spring Harbor Laboratory, a research and educational institution
www.biorxiv.org
October 14, 2023 at 3:58 PM