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Reposted by Chris Chatham

Adam Kucharski @adamjkucharski.bsky.social · Sep 1

Results so stunningly clear they inspired this classic xkcd (xkcd.com/2400/):

Chris Chatham @chchatham.bsky.social · Aug 26

I remain somewhat surprised reproducing MA isn't a solved problem by all the folks scrounging around for LLM use cases. One would think that LLMs+tools would have a ready-made training set for learning RL policies on tool calls / finetuning models in the history of meta-analyses published so far.

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Reposted by Chris Chatham

Nick Myers @nick-myers.bsky.social · Aug 26

New paper using M/EEG to look at attractive and repulsive serial dependence in working memory, led by the excellent Jiangang Shan, with Jasper Hajonides.

PLOS Biology @plosbiology.org · Aug 26

In #memories, when does bias towards or away from a stimulus arise? New research shows that attractive serial dependence emerges during #decision-making, while repulsive biases originate during early sensory encoding. 🧪
plos.io/3JSztEg

Attractive serial dependence arises during decision-making

Our memory of a stimulus can be biased toward or away from previous stimuli, but when this bias arises is unclear. This study shows that attractive serial dependence emerges during decision-making, su...

plos.io

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Chris Chatham @chchatham.bsky.social · Aug 25

In fairness, I doubt this aspect of my strategy is representative. I'm also engaging in the strategy you'd assumed (although not w/ any particular hope of success, and w/ a careful eye towards poisoning myself). Anyone seen a carefully reasoned piece on the options from a relevant expert/thinktank?

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Chris Chatham @chchatham.bsky.social · Aug 23

One sad lesson I take from Trump 2.0 is that the majority of Americans are no longer capable of reasoned debate. So I fear any liberal worldview that ties itself to that broken vehicle is doomed. A liberal dictum to entirely avoid such spaces requires very solid justification now more than ever IMO

Chris Chatham @chchatham.bsky.social · Aug 23

I understand the argument, but not the basis for believing this has any demonstrable record of success. I suspect we enable the propaganda more by evacuating the space of liberal views than we would by trying to poison the well (e.g., marking “not interested” on every ad, boycotting advertisers etc)

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Chris Chatham @chchatham.bsky.social · Aug 23

For one thing, it could just be another propaganda platform that we otherwise willfully grant to the right, adding to the seemingly-effective echo chambers they cultivate in various corners of the popular tech/science/lifestyle podcast world, FoxNews before that, and AM radio syndicate years earlier

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Chris Chatham @chchatham.bsky.social · Aug 23

No… I’m saying that despite not doing so, it may yet have value. To suggest the opposite - that its value derives exclusively from enabling debate amongst reasonable people - is potential folly, maybe one of those high-minded liberal values we need to reconsider in light of liberal losses.

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Reposted by Chris Chatham

Arif A. Hamid, Ph.D. @arifahamid.bsky.social · Aug 23

Proud of Amy and Nick, who review technical and theoretical gaps in timescales of dopamine fluctuations.

We argue that DA fluctuations are hierarchical control signals, and “tonic” DA relays goal alignment across planning horizons and C-BG hierarchy.

www.sciencedirect.com/science/arti...

Timescales of dopamine release in the striatum as a window into hierarchical control

The reinforcement learning community has made significant progress in understanding dopamine (DA) in reward learning, cognitive control, and motivatio…

www.sciencedirect.com

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Chris Chatham @chchatham.bsky.social · Aug 23

3 reasons: (1) many folks have no idea professors also do research; (2) it may be seen as gauche to ask, and risk forcing a distinction between research faculty and teaching faculty; (3) you can still respond with how you teach (publish) about what your research has found.

Chris Chatham @chchatham.bsky.social · Aug 22

I'm open to this but I question which high-minded liberal ideas need rethinking given our dismal performance among the evidently-unreasonable majority of American voters; I suspect that 'the value of a communication platform arises from its ability to engage reasonable parties in debate' may be one.

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Chris Chatham @chchatham.bsky.social · Aug 22

I confess I haven;t; it's a war of attrition IMO. I also don't think my contributions do much to legitimize the platform so, in the worst case, I see it mostly as a potential waste of time. I'm quote open to being persuaded, just haven't seen a comprehensive/balanced logical argument for vs against.

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Chris Chatham @chchatham.bsky.social · Aug 22

I also find the math unclear, and hence continue to engage there so as not to prematurely cede the ground. I concede this may not be terribly effective. But, it seems like the math must surely be clearer to you than you suggest, given the (rather ironically) extreme assertion in the OP!

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Chris Chatham @chchatham.bsky.social · Aug 21

This is an encouraging result for the use of EEG in a variety of applications going well beyond RSA.

Simon W Davis @woodforbrains.bsky.social · Aug 21

EEG representational analyses are more robust than fMRI. Huh.

link.springer.com/article/10.1...

How Robust Are fMRI- and EEG-Based Representational Similarity Analysis? - Computational Brain & Behavior

In EEG and fMRI analysis, researchers choose from a combinatorially large set of theoretically indistinguishable options while building a data processing pipeline based on individual beliefs and other...

link.springer.com

Chris Chatham @chchatham.bsky.social · Aug 21

Thanks for this great work! Can you explain a bit more about why you selected the similarity metrics you did? I was not sure whether there was a principled reason to use Spearman for dimensions, cosine for content and Pearson for brain or if this mixed bag of metrics simply worked best.

Reposted by Chris Chatham

Simon W Davis @woodforbrains.bsky.social · Aug 21

EEG representational analyses are more robust than fMRI. Huh.

link.springer.com/article/10.1...

How Robust Are fMRI- and EEG-Based Representational Similarity Analysis? - Computational Brain & Behavior

In EEG and fMRI analysis, researchers choose from a combinatorially large set of theoretically indistinguishable options while building a data processing pipeline based on individual beliefs and other...

link.springer.com

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Reposted by Chris Chatham

Tom Donoghue @tomdonoghue.bsky.social · Aug 21

I've updated my literature review of studies of aperiodic neural activity in clinical disorders, adding ~30 papers, taking it to 177 reports across 38 disorders!

It's got a review of results so far, discussion of themes & issues, & recommendations for future work!

www.medrxiv.org/content/10.1...

A systematic review of aperiodic neural activity in clinical investigations

Aperiodic neural activity - activity with no characteristic frequency - has increasingly become a common feature of study, including in clinical work. Reports investigating aperiodic activity from pat...

www.medrxiv.org

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Chris Chatham @chchatham.bsky.social · Aug 11

Very encouraging work; I'm inspired. What happened with the primary outcome (the LPP)? Regardless of whether the study was positive on its primary outcome, it's obvious there's something here worth exploring further. Congrats!

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Reposted by Chris Chatham

Donner Lab @donnerlab.bsky.social · Jun 27

1/ New paper by Hame Park, (@AraziAyelet), Bharath Talluri, Marco Celotto, Stefano Panzeri, Alan Stocker & Tobias Donner published in Nature Communications – “Confirmation Bias through Selective Readout of Information Encoded in Human Parietal Cortex”: rdcu.be/etlR7. Here is a summary:

Confirmation bias through selective readout of information encoded in human parietal cortex

Nature Communications - People often discard incoming information when it contradicts their pre-existing beliefs about the world. Here, the authors show that this discarded information is precisely...

rdcu.be

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Chris Chatham @chchatham.bsky.social · Apr 2

Super talented team working on an incredibly important problem. Congrats!

Christian Webb, PhD @christianwebb.bsky.social · Apr 2

Excited and grateful to have received an R01 to expand our lab's work using passively collected data from smartphones and wearables to detect negative emotional states and predict depression risk in youth (working w/ Justin Baker, Habib Rahimi, and Boyu Ren)

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Chris Chatham @chchatham.bsky.social · Mar 25

Denali describing their approach to shuttle large molecules as cargo across the blood brain barrier. We should see new clinical data from approaches like this already in 2025. Exciting time for neurotherapeutics for this and so many other reasons...

bioRxiv Neuroscience @biorxiv-neursci.bsky.social · Mar 25

Dual targeting of transferrin receptor and CD98hc enhances brain exposure of large molecules https://www.biorxiv.org/content/10.1101/2025.03.24.645085v1

Reposted by Chris Chatham

bioRxiv Neuroscience @biorxiv-neursci.bsky.social · Mar 25

Dual targeting of transferrin receptor and CD98hc enhances brain exposure of large molecules https://www.biorxiv.org/content/10.1101/2025.03.24.645085v1

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Reposted by Chris Chatham

bioRxiv Neuroscience @biorxiv-neursci.bsky.social · Mar 25

Intellectual ability and cortical homotopy development in children and adolescents https://www.biorxiv.org/content/10.1101/2025.03.24.645014v1

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Reposted by Chris Chatham

Darren Dahly @statsepi.bsky.social · Mar 24

Here is the video I made, inspired by this wonderful tweet.

www.youtube.com/watch?v=dSOj...

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Chris Chatham @chchatham.bsky.social · Feb 26

Oh - I shoudl also thank @darkhat.bsky.social for sending along this fascinating paper in our now years-long science + everything chat! Keep an eye out for a killer paper, on a totally different topic, coming from his team soon...