The supply of blood to brain tissue is thought to depend on the overall neural activity in that tissue, and this dependence is thought to differ across brain regions and across brain states. However, studies supporting these views have measured neural activity as a bulk quantity and related it to blood supply following disparate events in different regions. Here we measure fluctuations in neuronal activity and blood volume across the mouse brain, and find that their relationship is consistent across brain states and brain regions but differs in two opposing brainwide neural populations. Functional ultrasound imaging (fUSI) revealed that whisking, a marker of arousal, is associated with brainwide fluctuations in blood volume. Simultaneous fUSI and Neuropixels recordings showed that neurons that increase activity with whisking have distinct haemodynamic response functions compared with those that decrease activity. Their summed contributions predicted blood volume across states.Brainwide Neuropixels recordings revealed that these opposing populations coexist in the entire brain. Their differing contributions to blood volume largely explain the apparent differences in blood volume fluctuations across regions. The mouse brain thus contains two neural populations with opposite relations to brain state and distinct relationships to blood supply, which together account for brainwide fluctuations in blood volume.

How does blood flow relate to brain activity? We discovered that it reflects two neural populations affected oppositely by arousal. Together, they explain neurovascular coupling in all brain regions and brain states!

Out today in Nature: rdcu.be/fdC2A

@uclbrainscience.bsky.social

You have more in common with the people of Iran than you do with anyone in this administration, any member of the technocracy, anyone who is profiting from this war, or any billionaire. When you see Iranians forming human chains outside key infrastructure sites, you should feel a sense of kinship.

Protect Academic Life in Iran We, the undersigned academics and researchers from around the world, express our profound concern over recent military strikes on Iran, the retaliatory responses, and the reported impact on civilian l...

Academic friends,
It's beyond heartbreaking to watch what's unfolding in Iran & the region.
A few of us drafted an open letter calling for protection of civilians & of educational, research, medical & cultural institutions.

Please read & sign if you agree:
sites.google.com/view/protect...

#IranWar

⚠️ If you are in the Pentagon today working to JUSTIFY a target list including clearly civilian infrastructure, you are complicit in war crimes.

You swore an oath. You have a duty to say "no."

The consequences will be rough, but obeying will be worse.

Four headlines in which Marjorite Taylor Greene, Tucker Carolson, Piers Morgan, and Alex Jones condemn Trump for his genocidal threats to Iran.

Imagine being a moderate Republican and getting outflanked on decency, morality, and basic humanity by these four nutters

I'm getting nauseous from pingponging between joy and wonder at the Artemis mission and rage and horror at the threats of a leader who is clearly too unhinged and unstable to be in a position of power, but whose party continues propping him up because they love power more than reason or humanity

Being an American is absolutely mortifying. I am so sorry we live in a country of morons, racists, misogynists and bigots who voted for this man. I don’t know what to do. We screamed for a decade about Trump being an unhinged psychopath and they did not listen.

Some reports say over 500 schools, 55 libraries, & 25 universities hit.
You can debate the numbers, but hitting Sharif University & Beheshti is like hitting MIT & Stanford. I keep wondering: How would the scientific community respond differently if it was those universities? What’s the difference?

The NSF 2027 budget has noted that they will close out the Social, Behavioral, and Economic Science Program (SBE). This is not a good thing. nsf-gov-resources.nsf.gov/files/FY-202...

Arson: “At an internal all-hands meeting on Friday, NSF leaders announced that they would dissolve the agency’s Social, Behavioral and Economic Sciences directorate based on the budget request, according to two NSF staff members who shared information anonymously in order to speak freely”

We’re hiring a full-time Research Coordinator in the Preston Lab at UT Austin (start May/June 2026).

Work on behavioral + fMRI studies of how memory & decision-making develop from childhood to adulthood.

Learn more & apply: preston.clm.utexas.edu/news/join-th...

Please repost!

Trump Administration Readies Plans to Dismantle Renowned Science Lab

This should be the biggest weather and climate news on your radar today.

You can send an email today to say why dismantling NCAR is a bad idea for everyone: NSF_NCAR@nsf.gov

Portrait of Judith Ellen Fan, a woman with straight dark hair and short bangs, smiling at the camera and wearing a dark green blouse and a delicate geometric necklace. Set against a teal background, the graphic reads: “Congratulations to Judith Ellen Fan (Stanford University), winner of the 2026 Lila R. Gleitman Prize for Early-Career Contributions to Cognitive Science.”

Congratulations to Judith Ellen Fan @judithfan.bsky.social, recipient of the 2026 Lila R. Gleitman Prize.

Dr. Fan's research reflects the broad scope of modern #CogSci, bridging #psychology, #neuroscience, vision science, and #education.

Learn more at cognitivesciencesociety.org/gleitman-prize/

The Trump Administration Is Ending Aid That It Says Saves Lives The State Department will let lifesaving projects expire because “there is no strong nexus between the humanitarian response and U.S. national interests,” according to an internal email.

Quietly, the Trump administration is now ending even the life-saving aid that they had promised would be preserved

Reporting from @hana-kiros.bsky.social

www.theatlantic.com/health/2026/...

Building compositional tasks with shared neural subspaces Nature - The brain can flexibly perform multiple tasks by compositionally combining task-relevant neural representations.

Thrilled that my paper is out in the @nature.com. We explored how the brain builds complex tasks by compositionally combining simpler sub-task representations. The brain flexibly performs multiple tasks by dynamically reusing neural subspaces for sensory inputs and motor actions

rdcu.be/eRVUk

Excited to share a new paper spearheaded by the wonderful @baror-shira.bsky.social:
tinyurl.com/bd8xdcum
@erc.europa.eu @nathumbehav.nature.com

We test the link between serial dependence (as an index of continuity) and event boundaries (indexing segmentation). A few key findings in the thread:

A group, one of many, holding candles in honor of a community member executed by an unaccountable paramilitary invasion force

This is Minneapolis.

Literally every corner along Lake St. packed with people holding candles, many singing, honoring a person who by all accounts was an absolute gem of a human, whose life was tragically stolen by a fascist, paramilitary occupation force.

This is Alex Pretti.

A video of Alex Pretti reading out the final salute of an unnamed veteran he cared for until the end of his life in the ICU, posted to Facebook by his son.

John Mitnick @JohnMitnick I helped to establish DHS in 2002 and 2003 and later had the homeland security portfolio as a White House Counsel and served as General Counsel of the Department. I am enraged and embarrassed by DHS’s lawlessness, fascism, and cruelty. Impeach and remove Trump—now. George Conway ⚖️🇺🇸 @gtconway3d The deadly shooting in Minneapolis today was a straight-up execution of a protester by Trump's federal brownshirts. The thugs wrestled him to the ground. They pistol-whipped him, then shot him multiple times. They murdered him.

Beyond helping establish DHS itself in 2003, Mr. Mitnick was a senate-confirmed Trump choice for General Counsel for DHS in his first term. I've talked with him a few times, and he's not a man for hyperbole. So bear that in mind when you see him calling out DHS's "lawlessness, fascism, and cruelty."

man the stuff i am seeing on IG from
the most normie, i don’t really talk about politics accounts suggests something different

U.S. overhauls childhood vaccine schedule, recommends fewer shots The U.S. no longer broadly recommends vaccines for flu, hepatitis A and B, and RSV. Health officials say the guidance aligns with that of peer countries.

This is a five alarm fire. If you dont think this impacts you, think again. Public health is in grave danger www.washingtonpost.com/health/2026/...

Trump’s Immigration Nightmare: It Is Happening Here With astonishing speed, the administration has toppled the most cherished pillars of a free society. And the experts agree: It’s all going to get much, much worse.

So I have the cover story in next month's TNR.

I interviewed the heads of police groups; immigration defense attorneys, ex-judges and ex-prosecutors; former DOJ and DHS officials, and the former head of Border Patrol.

They're all horrified at what we've seen, and they all fear what's coming.

We are recruiting a lab manager/research assistant to start in early 2026! The successful candidate will conduct awake infant fMRI, meet cute babies, and join a fun team!

More details (e.g. responsibilities): soc.stanford.edu/people/#join...

Apply here: careersearch.stanford.edu/jobs/social-...

I will be recruiting 🌟PhD students🌟 for my newish lab! If you're interested in learning & memory mechanisms applied to individual, interactive & collective behavior using computational modeling, real-world experiments and fMRI, email me! RTs much appreciated 🙏 rouhanilab.com

Out now in @nathumbehav.nature.com! We applied graph theoretic analyses to fMRI data of participants watching movies/listening to stories. Integration across large-scale functional networks mediates arousal-dependent enhancement of narrative memories. Open access link: rdcu.be/eKKAw

You learn better when you test yourself on an answer before you study it? Even more counterintuitive, our findings showcase that there is not one direct mechanism to this effect.
Thank you @charan-neuro.bsky.social , @xiaonanl.bsky.social , and @jameswardantony.bsky.social !
doi.org/10.1037/xlm0...

A neural network with episodic memory learns causal relationships between narrative events Humans reflect on past memories to make sense of an ongoing event. Past work has shown that people retrieve causally related past events during comprehension, but the exact process by which this causa...

How does the brain🧠 make causal inferences and use memories to understand narratives🎬?

We built an RNN🤖 with key-value episodic memory that learns causal relationships between events and retrieves memories like humans do!

Preprint www.biorxiv.org/content/10.1...

w/ @qlu.bsky.social, Tan Nguyen &👇

Repeated Viewing of a Narrative Movie Changes Event Timescales in The Brain Many experiences occur repeatedly throughout our lives: we might watch the same movie more than once and listen to the same song on repeat. How does the brain modify its representations of events when...

How do the brain’s event representations change as we gain familiarity with an experience?

Brain regions’ representations can become coarser or finer as event familiarity increases. Fine-tuning predicts memory recall.

Excited to share this work with Narjes Al-Zahli & @chrisbaldassano.bsky.social!