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Arthur Prat

@arthurpr4t.bsky.social
180 followers 89 following 37 posts

Computational cognitive neuroscience. Perception, representation, inference and decision-making. Postdoc at Harvard with Sam Gershman. arthurprat.com

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Reposted by Arthur Prat
gillesdehollander.bsky.social @gillesdehollander.bsky.social · 21/09/2026
New paper in Nature Communications 🧠 Rapid Changes in Risk Attitudes Originate from Bayesian Inference on Parietal Magnitude Representations. Why the same person can flip between a safe bet and a gamble, and what parietal cortex has to do with it. 🧵 www.nature.com/articles/s41...
nature.com
Rapid changes in risk attitudes originate from Bayesian inference on parietal magnitude representations - Nature Communications
Risk attitudes can shift across contexts and even between identical choices. Here, the authors show that as parietal payoff representations grow noisier, the brain leans more on prior beliefs, biasing...
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Arthur Prat @arthurpr4t.bsky.social · 09/09/2026
We derived six laws of psychophysics from a single efficient-coding equation. The laws include Weber's law; scaling laws in visual working memory (which had been noted before, but with unclear theoretical justification); Wei & Stocker's law of human perception; arthurprat.com/pdfs/Prat-Ca...
arthurprat.com
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Reposted by Arthur Prat
Vinny Costa @vincentcostaphd.bsky.social · 07/09/2026
More stories like this one, please and thank you www.nytimes.com/2026/09/06/s...
nytimes.com
The 92-Year-Old Mathematician and the Teenage Apprentice
Joan Birman thought her major discoveries were behind her. Then came an email from a young neighbor — a girl who knew little but wanted to learn.
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Arthur Prat @arthurpr4t.bsky.social · 21/08/2026
We broke Weber's law. By manipulating the prior (ie the frequencies of small and large magnitudes), we changed how people's accuracy depended on magnitude. When large magnitudes were more frequent, subjects became more precise about them. This points to efficient coding, dynamically implemented.
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Reposted by Arthur Prat
Blair Shevlin @bshev.bsky.social · 20/08/2026
Now published in eLife: elifesciences.org/articles/103... We find strong evidence that activity in Pre-SMA and vmPFC scales with gaze-weighted accumulated evidence, suggesting attention directly modulates value signals in canonical decision-making circuits! 🧵 on the methods + findings:
elifesciences.org
Overt visual attention modulates decision-related signals in the frontal cortex
Brain activity in the pre-supplementary motor area and dorsolateral prefrontal cortex represents gaze-weighted accumulated evidence signals in value-based decision-making.
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Reposted by Arthur Prat
samuel mehr @mehr.nz · 16/07/2026
calling all researchers who collect data from humans 🧠🧪 we are running a very brief survey (<1 min) about jsPsych, the software ecosystem for browser-based data collection. if you use jsPsych, or if you collect data with any other software, please fill it out at tinyurl.com/jspsych-census!
I am writing on behalf of the leadership of jsPsych, the software ecosystem for browser-based data collection used in experiments and surveys from many labs worldwide.

It has been difficult for us to figure out how widespread jsPsych usage is, because the software is freely available online and we do not collect any information about downloads, users, experiments posted online, etc. While the software has been cited in thousands of articles, jsPsych usage is likely more widespread than those citations imply, because not every project using jsPsych leads to a citation, and because there are also often substantial delays between actual jsPsych usage and a publication. As such, we are conducting a very brief census of jsPsych users.

If you collect data from humans using jsPsych or any other type of software, we would appreciate your filling out a very brief survey (<1 min) at tinyurl.com/jspsych-census. This will help us to understand how many people, labs, and institutions are current or former users of jsPsych, information that will help support the long-term sustainability of the jsPsych ecosystem.

We would also appreciate it if you could circulate this message to your lab, your department listserv, and your collaborators, to help ensure that it reaches as many members of the research community as possible. The survey is being distributed by Josh de Leeuw, Melissa Kline Struhl, and myself. Please contact me (sam@auckland.ac.nz) off-list if you have any questions about it.
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Arthur Prat @arthurpr4t.bsky.social · 25/06/2026
To adapt to a new prior, tuning curves should "move" toward more frequent stimuli ('prior attraction'). But in adaptation studies they are shown to move away from the more frequent stimuli ('adapter repulsion'). Oh also how do tuning curves move at all?? www.nature.com/articles/s41...
nature.com
Fast efficient coding and sensory adaptation in gain-adaptive recurrent networks - Nature Communications
How sensory systems rapidly adapt to changing stimulus statistics remains unclear. Here the authors show that gain adaptation in recurrent networks can implement fast efficient coding, unifying prior ...
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Arthur Prat @arthurpr4t.bsky.social · 21/06/2026
These days the expected value of the Massachusetts Megabucks lottery is positive, so I expect every economist and decision theorist in Massachusetts will get their ticket. If you don't buy, clearly something must be wrong with your utility function
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Arthur Prat @arthurpr4t.bsky.social · 20/05/2026
There's no eye in AI
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Arthur Prat @arthurpr4t.bsky.social · 21/04/2026
The "Version of Record" of my paper with Mike Woodford is finally there. I am very glad with this paper that points to new laws of psychophysics, which we derived from a carefully considered principle of endogenous efficient coding.
elifesciences.org
Endogenous precision of the number sense
A theory of efficient coding wherein the precision of representations is endogenous, task-dependent, and prior-dependent predicts scaling laws for imprecision and is supported by numerosity perception...
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Arthur Prat @arthurpr4t.bsky.social · 15/04/2026
Isaiah Berlin on FDR in the 1930s: "... to construct a regime which should provide for greater economic equality and social justice - ideals which were the best part of the tradition of American life - without altering the basis of freedom and democracy in his country." Where is our Roosevelt!
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Reposted by Arthur Prat
Pierre-Etienne Fiquet @pfiquet.bsky.social · 26/03/2026
Applications are now open for our Junior Theoretical Neuroscientists Workshop which will take place July 21 - 24, 2026 at the Center for Computational Neuroscience @flatironinstitute.org Learn more and apply by April 15 at www.simonsfoundation.org/event/jrwork...
simonsfoundation.org
Junior Theoretical Neuroscientists Workshop
Junior Theoretical Neuroscientists Workshop on Simons Foundation
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Arthur Prat @arthurpr4t.bsky.social · 27/03/2026
Just posted an update of this study, where we show how the receptive fields of number-encoding neural populations shift and rescale with the prior — "distributed range adaptation" — in line with (dynamic) efficient coding, and predictive of behavior. Check it out! www.biorxiv.org/content/10.1...
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Reposted by Arthur Prat
Sam Gershman @gershbrain.bsky.social · 17/07/2025
Efficient coding theories often implicitly or explicitly assume slow changes in tuning (e.g., through synaptic plasticity). Arthur Prat-Carrabin has collected psychophysical data showing that it can be fast, and this can be explained by a gain-adaptive RNN: www.biorxiv.org/content/10.1...
biorxiv.org
Fast efficient coding and sensory adaptation in gain-adaptive recurrent networks
As the statistics of sensory environments often change, neural sensory systems must adapt to maintain useful representations. Efficient coding prescribes that neuronal tuning curves should be optimize...
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