Eric Garr
@garrface.bsky.social
📤 796
📥 464
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Postdoc @ Johns Hopkins. Behavior, brains, biking, bagels. ericgarr.com
pinned post!
I’m excited to share my latest paper, in which we used latent state modeling to reveal how fentanyl shapes decision-making dynamics in rats. Here’s a summary of what we found (thread).
www.biorxiv.org/content/10.1...
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Modeling hidden cognitive states reveals acute and chronic effects of fentanyl on decision-making
The cognitive mechanisms underlying behavior are often dynamic, shifting gradually or abruptly over time scales spanning years, to weeks, to minutes. Whether drug-induced changes in learning and decis...
https://www.biorxiv.org/content/10.1101/2025.08.04.668448v1
8 months ago
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Eric Garr
Ann Kennedy
9 days ago
transformer-circuits.pub/2026/emotion...
This got press hate because of the word "emotions" but it is cool work. "Internal motivational states" serve as a form of working memory that helps animals organize their behavior, so why not ask if similar computational primitives help LLMs to do the same?
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Emotion Concepts and their Function in a Large Language Model
https://transformer-circuits.pub/2026/emotions/index.html
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Hey
@ditzkoff.bsky.social
I knew I recognized you! Sorry for the identity mishap, trying to work on my journalist vs. neuroscientist decoder.
8 days ago
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Mark Histed
13 days ago
This is only true for people who understand neither science nor economics. The NIH budget for this year is FIFTY times larger than OpenAI’s $1B pledge. The foundation of US science & innovation is public funding. The private sector cannot replace it. US science is being killed
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Sam Gershman
14 days ago
@jhennig.bsky.social
has shown that dopamine exerts a real-time effect on conditioned responding, beyond its role in learning:
www.biorxiv.org/content/10.6...
Another indication that dopamine is more than a learning signal! A joint effort with
@naoshigeuchida.bsky.social
and
@mhburrell.bsky.social
.
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Remember this example whenever anyone tells you that you’re generally safe living in a blue city within a red state (something I was told frequently while on the faculty job market)
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20 days ago
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Alex Williams
23 days ago
Cosyne invited me to give a long tutorial (4 hours!) on methods to quantify differences high-d neural recordings across animals, brain regions, deep neural nets, etc. The recording is up on youtube. I hope it inspires more research on this fundamental topic!
www.youtube.com/watch?v=n44x...
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Cosyne 2026 - Cosyne Tutorial: Comparative Analysis of Neural Population Codes
YouTube video by Cosyne Talks
https://www.youtube.com/watch?v=n44xqrZ5j9U
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Eric Garr
Arc Institute
about 1 month ago
Today in
@nature.com
, the
@christophthaiss.bsky.social
&
@maayanlevy.bsky.social
labs trace age-related memory loss to the gastrointestinal tract & map the complete gut-to-brain pathway driving it. Targeting this pathway can reverse cognitive aging in mice.
www.nature.com/articles/s41...
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Ben Saunders
about 1 month ago
Check out our latest research drop! We show BLA dopamine signaling encodes the emotional weight of sensory transitions, but not the associative strength or value of stimuli. These signals dynamically rescale when the learning context changes: "this matters most!"
www.biorxiv.org/content/10.1...
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https://www.biorxiv.org/content/10.1101/2025.05.15.654323v2
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Drug Monkey
about 1 month ago
NIH Director Bhattacharya signals an end to the affirmative action program for ESI
drugmonkey.wordpress.com/2026/02/26/n...
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NIH Director Bhattacharya signals an end to the affirmative action program for ESI
Well, this is fascinating. Director Jayanta Bhattacharya went on the Why Should I Trust You podcast in an episode dated Feb 26, 2026 [h/t]. Around 59:00 he is answering the podcast host after she p…
https://drugmonkey.wordpress.com/2026/02/26/nih-director-bhattacharya-signals-an-end-to-the-affirmative-action-program-for-esi/
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Here's a quick analysis I did on data I've been collecting on psych/neuro faculty applicants. I don't have data on unsuccessful applicants, but my inference is that women mentored by women have to rely more on bringing in $ to get a faculty job than men mentored by men.
about 2 months ago
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Vijay Mohan K Namboodiri
about 2 months ago
Very excited to post our paper led by
@daburke.bsky.social
www.nature.com/articles/s41...
where we uncover a simple mathematical rule underlying how brains learn that a cue predicts a reward. 1/26
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Duration between rewards controls the rate of behavioral and dopaminergic learning - Nature Neuroscience
Cue–reward learning rate scales proportionally with the time between rewards. Consequently, learning over a fixed duration is independent of the number of trials. This challenges trial-based dopamine ...
https://www.nature.com/articles/s41593-026-02206-2
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Now published in Neuropharmacology!
www.sciencedirect.com/science/arti...
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2 months ago
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Greg Folkers
3 months ago
Science: U.S. government has lost more than 10,000 STEM Ph.D.s since Trump took office By Jeffrey Mervis, Monica Hersher
@science.org
@policyhound.bsky.social
@mghersher.bsky.social
bit.ly/3M8yf9B
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U.S. government has lost more than 10,000 STEM Ph.D.s since Trump took office
A Science analysis reveals how many were fired, retired, or quit across 14 agencies
https://bit.ly/3M8yf9B
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Since the Namboodiri lab isn’t on Bluesky (I think?), I’d like to amplify this cool paper which I and others in the Janak lab made a small contribution to.
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3 months ago
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Jeremy Berg
3 months ago
The conference (agreement between House and Senate) appropriations bill that includes HHS and NIH was released this morning.
www.appropriations.senate.gov/news/majorit...
1/5
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Committee Releases Conferenced Defense, Homeland Security, Labor, Health and Human Services, Education, and Related Agencies, and Transportation, Housing and Urban Development, and Related Agencies Bi...
United States Senate Committee on Appropriations
https://www.appropriations.senate.gov/news/majority/committee-releases-conferenced-defense-homeland-security-labor-health-and-human-services-education-and-related-agencies-and-transportation-housing-and-urban-development-and-related-agencies-bills
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Crawford Kilian
3 months ago
A long, absolutely must-read article from Cory Doctorow:
www.theguardian.com/us-news/ng-i...
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AI companies will fail. We can salvage something from the wreckage | Cory Doctorow
AI is asbestos in the walls of our tech society, stuffed there by monopolists run amok. A serious fight against it must strike at its roots
https://www.theguardian.com/us-news/ng-interactive/2026/jan/18/tech-ai-bubble-burst-reverse-centaur
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Roddy Grieves
3 months ago
Can humans & animals really use internal maps to take shortcuts? Tolman famously said yes - based largely on his Sunburst maze. Our new review & meta-analysis suggests evidence is far weaker than you might think. 🧵👇
doi.org/10.1111/ejn....
@uofgpsychneuro.bsky.social
@ejneuroscience.bsky.social
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Tolman's Sunburst Maze 80 Years on: A Meta‐Analysis Reveals Poor Replicability and Little Evidence for Shortcutting
In 1946, Tolman et al. reported that rats could take a novel shortcut to a goal after training on an indirect route, supporting the Cognitive Map theory. However, a review of subsequent Sunburst maze...
https://doi.org/10.1111/ejn.70365
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Dr Kathleen Millen
3 months ago
I don't think you non-science people realize what it takes to get a grant funded by NIH. Started experiments in Sept 2021 to generate 3 new mouse mutants to model human disease. Prelim dara shows they have relevant disease phenotypes worthy of study. Need a small grant first to characterize /1
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Arif A. Hamid, Ph.D.
3 months ago
Excited to share latest study from the lab by an amazing RA, Dylan Flink. We solved a small (important) puzzle while in the trenches of a larger (wavy 🌊) puzzle.
www.biorxiv.org/content/10.6...
🧵...
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Dual cholinergic mechanisms for sculpting striatal dopamine in vivo
Striatal dopamine (DA) and acetylcholine constitute a computationally powerful neuromodulatory dyad that orchestrates action selection, motivational vigor, and reward learning. Striatal cholinergic in...
https://www.biorxiv.org/content/10.64898/2025.12.19.695021v1.abstract
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Tim Verstynen
4 months ago
Sleep dependent consolidation and replay that doesn’t require the hippocampus? Very beautiful work by Marcus Stephenson-Jones’ lab on sleep driven sequential skill consolidation in the striatum.
www.biorxiv.org/content/10.1...
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https://www.biorxiv.org/content/10.1101/2024.06.05.597547v1
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Munir “Gunes” Kutlu
4 months ago
🚨New Kutlu Lab preprint! Excited to share our latest work led by Oyku Dinckol and Noah Wenger. 🔗
www.biorxiv.org/content/10.6...
We find that ACh shapes DLS neural ensembles for outcome learning but is biased toward signaling threats over rewards 👇
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Dorsolateral striatal acetylcholine reorganizes neural ensembles to anticipate threat
Adaptive behavior requires flexible encoding of emotional valence. Although striatal acetylcholine (ACh) signaling is critical for reinforcement learning, its contribution to aversive learning has rem...
https://www.biorxiv.org/content/10.64898/2025.12.10.693585v1
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Drug Monkey
4 months ago
22% fewer NIH grants
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Dan Goodman
5 months ago
Nature Sci Rep publishes incoherent AI slop. eLife publishes a paper which the reviewers didn't agree with, making all the comments and responses public with thoughtful commentary. One of these journals got delisted by Web of Science for quality concerns from not doing peer review. Guess which one?
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Ben Saunders
5 months ago
So excited to see our latest paper out today in
@natcomms.nature.com
! Studies led by the amazing
@margestelzner.bsky.social
www.nature.com/articles/s41...
. VTA GABA neurons have a unique role in economic decision making - they integrate reward seeking motivation and the current cost of seeking
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Ventral tegmental area GABA neurons integrate positive and negative valence - Nature Communications
The role of ventral tegmental area GABA neurons in behavior is unclear. Here, authors show that VTA GABA but not dopamine neurons integrate positive and negative valence to encode motivational conflic...
https://www.nature.com/articles/s41467-025-65345-3
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Eric Garr
Mel Sharpe
5 months ago
Good morning everyone! Suitably following the
#dopamine
dinner, we have our
#dopamine
symposium at 9:30am in SDCC room 6B! ‘Beyond Value: Non-canonical roles for dopamine in aversion and reward’ Come join us! 🧠 🧪
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If you're at SfN on Monday, come by poster board II10 to see how fentanyl changes cell type-specific encoding of choice outcomes in the striatum to influence decision-making phenotypes. Looking forward to seeing some cool science and supporting SfN during these difficult times!
5 months ago
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If you're at SfN on Monday, come by poster board II10 to see how fentanyl changes cell type-specific encoding of choice outcomes in the striatum to influence decision-making phenotypes. Looking forward to seeing some cool science and supporting SfN during these difficult times!
5 months ago
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Eric Garr
Nicolas Tritsch
5 months ago
Delighted to see this finally out:
rdcu.be/eO9oW
We tested whether brief striatal dopamine release events influence the vigor of skilled movements. Despite popular belief, we did not find any evidence linking rapid dopamine dynamics to motor vigor on a moment-by-moment basis.
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Subsecond dopamine fluctuations do not specify the vigor of ongoing actions
Nature Neuroscience - Liu and colleagues show that the vigor (that is, speed and amplitude) of dexterous movements is not controlled by ongoing fluctuations in extracellular dopamine within the...
https://rdcu.be/eO9oW
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Eric Garr
bioRxiv Neuroscience
5 months ago
VTA dopamine neuron activity produces spatially organized value representations
https://www.biorxiv.org/content/10.1101/2025.11.04.685995v1
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Eric Garr
Tomer Ullman
5 months ago
Nature suggests you use their "Manuscript Adviser" bot to get advice before submitting I uploaded the classic Watson & Crick paper about DNA structure, and the Adviser had this to say about one of the greatest paper endings of the century:
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I first heard Jack DeJohnette as part of the Keith Jarrett trio when I was ~14. I didn’t like his drumming and thought it sounded sloppy. For whatever reason, it clicked with me much later. Here’s a 🔥 clip I discovered recently. RIP JD
youtu.be/a3CZHr5uiNM?...
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Jack DeJohnette, Pat Metheny, Herbie Hancock and Dave Holland - Shadow Dance (live)
YouTube video by SafaJah
https://youtu.be/a3CZHr5uiNM?si=gMaAW6KyCEwvjB-I
6 months ago
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Eric Garr
Phil Corlett
6 months ago
Some great consideration of differences in learning and performance during blocking (the sine qua non of PE phenomena) in sign vs goal trackers here:
www.sciencedirect.com/science/arti...
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Behavioral determinants in the expression of the Kamin blocking effect: Implications for associative learning theory
Associative learning makes important contributions to our behavior and decisions. The Kamin blocking effect is an associative learning phenomenon that…
https://www.sciencedirect.com/science/article/abs/pii/S0149763421000257
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Eric Garr
Drew Schreiner
6 months ago
Nice preprint from Veronica Alvarez's group on cortically-evoked DA mediated by ACh! I We observed something quite similar in birds, and interesting to see the sensory/prefrontal distinction
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Cholinergic-dependent dopamine signals in mouse dorsal striatum are regulated by frontal but not sensory cortices
Everyday decisions depend on linking sensory stimuli with actions and outcomes. The striatum supports these sensorimotor associations through dopamine-dependent plasticity. Thus, the timing and magnit...
https://www.biorxiv.org/content/10.1101/2025.09.30.679538v1
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Sean Ostlund
6 months ago
We have an open NIH-funded postdoc position in the lab to study circuit and neurochemical mechanisms of cognitive and motivational deficits in opioid withdrawal. Apply here:
recruit.ap.uci.edu/JPF09885
or message/email for more information.
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Postdoctoral Scholars - Ostlund Laboratory - Anesthesiology & Perioperative Care
University of California, Irvine is hiring. Apply now!
https://recruit.ap.uci.edu/JPF09885
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Eric Garr
Mark Laubach
6 months ago
I'm recruiting a PhD student to study how enkephalins affect cognitive processing in the rodent frontal cortex. The project uses pharmacology, multi-electrode recordings, and fiber photometry, and is funded by NIDA. Please share with trainees applying this cycle. Thanks!
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Eric Garr
Drug Monkey
7 months ago
This may be the most important paper ever published about NIH funded research.
www.science.org/doi/10.1126/...
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What if NIH had been 40% smaller?
Replaying history with less NIH funding shows widespread impacts on drug-linked research
https://www.science.org/doi/10.1126/science.aeb1564
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bioRxiv Neuroscience
7 months ago
A mechanistic theory of planning in prefrontal cortex
https://www.biorxiv.org/content/10.1101/2025.09.23.677709v1
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Ali Mohebi
7 months ago
Today 1-2 pm CST
bit.ly/3VOJrcy
Join us!
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Eric Garr
Malcolm Campbell
7 months ago
🚨Our preprint is online!🚨
www.biorxiv.org/content/10.1...
How do
#dopamine
neurons perform the key calculations in reinforcement
#learning
? Read on to find out more! 🧵
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Serge Ahmed
7 months ago
This article is truly impressive, both for the significance of its findings and the enormous amount of work it represents! Briefly, it demonstrates that the gut-brain vagal axis exerts a considerable influence on dopamine-dependent reward-related processes... 1/n
www.biorxiv.org/content/10.1...
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Thomas Luo
7 months ago
How does the brain decide? 🧠 Our new
@nature.com
paper shows that neural activity switches from an 'evidence gathering' to a 'commitment' state at a precise moment we call nTc. After nTc, new evidence is ignored, revealing a neural marker for the instant when the mind is made up.
rdcu.be/eGUrv
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Transitions in dynamical regime and neural mode during perceptual decisions - Nature
Simultaneous recordings were made of hundreds of neurons in the rat frontal cortex and striatum, showing that decision commitment involves a rapid, coordinated transition in dynamical regime and neura...
https://www.nature.com/articles/s41586-025-09528-4
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Gregg Gonsalves
7 months ago
Though it’s traumatic for me to bring this up, I was targeted by a group allied with Turning Point USA in 2018, with the help of Tucker Carlson on Fox. My home address circulated online and I got death threats. 1/
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Ian L Morgan
7 months ago
Director Bhattacharya says there are no banned words at the NIH. The data suggest otherwise.
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Ali Mohebi
7 months ago
I am beyond excited to host a stellar group of scientists for the first installation of our series: Brain Talks on The Isthmus. Thank you to everyone who contributed by spreading the news, submitting abstracts, reviewing the submissions, and offering kind words of support. I am grateful and smiling
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Kishore Kuchibhotla
7 months ago
🚨 We’re hiring a postdoc! 🚨 Excited for our new NiCE grant with
@lauerlab.bsky.social
@batwoman123.bsky.social
🎉We use a comparative approach, two-photon imaging & optogenetics to identify why bats🦇 and deer mice resist noise but lab mice don't. If you're interested, please DM or e-mail me!
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Siri Leknes
8 months ago
What can *genetic insensitivity to opioids* teach us about endogenous opioid function in humans? Fully funded position in Oslo (PhD student or postdoc) Interested in pain, mu/kappa opioids, behavioural genetics, RCTs, or related? Apply here:
2411.webcruiter.no/Main2/Recrui...
Please RT for reach
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Phd candidate or postdoc– Genetic determinants of opioid responsiveness
The Department of Research and Development at the Division of Emergencies and Critical Care, Oslo University Hospital in collaboration with Leknes Affective Brain lab (www.affectivebrains.com) and the...
https://2411.webcruiter.no/Main2/Recruit/Public/5008017264?link_source_id=0
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Eric Garr
Steve Vladeck
8 months ago
TL;DR: 5 justices say Trump doesn't have to immediately restore the funding, but 5 *also* signal that the underlying directives are unlawful. That sends a fairly strong (if mixed) message that Trump will lose these cases *eventually,* but only once they're brought in the Court of Federal Claims.
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Stand Up for Science!
8 months ago
🚨BREAKING NEWS: RFK Jr. is a danger to this nation. Don’t give in to Trump & his cronies: we are NOT trading innovation for ideology. We demand the immediate IMPEACHMENT and REMOVAL of RFK. Stop the quack. Protect Science. Protect Democracy Sign & share here:
zurl.co/PEPyD
#StandUpForScience
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Dave Levitan
8 months ago
This op-ed from NIH director Jay Bhattacharya is *infuriating*. He says we have to stop funding mRNA vaccine research because it hasn't "earned public trust." Motherfucker, WHO DID THAT.
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Opinion | Jay Bhattacharya: Why the NIH is pivoting away from mRNA vaccines
As a vaccine for broad public use, mRNA technology has failed to earn the public’s trust.
https://www.washingtonpost.com/opinions/2025/08/12/nih-mrna-vaccines-jay-bhattacharya/
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I’m excited to share my latest paper, in which we used latent state modeling to reveal how fentanyl shapes decision-making dynamics in rats. Here’s a summary of what we found (thread).
www.biorxiv.org/content/10.1...
loading . . .
Modeling hidden cognitive states reveals acute and chronic effects of fentanyl on decision-making
The cognitive mechanisms underlying behavior are often dynamic, shifting gradually or abruptly over time scales spanning years, to weeks, to minutes. Whether drug-induced changes in learning and decis...
https://www.biorxiv.org/content/10.1101/2025.08.04.668448v1
8 months ago
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