Catrina Hacker

Turning pages, swiping screens, and hitting play: Is reading always the same to our brain? Whether it’s on paper, screen or audio, there are more ways than ever to enjoy a good book. But do different formats engage the brain in the same way?

Whether it’s on paper, screen or audio, there are more ways than ever to enjoy a good book. But do different formats engage the brain in the same way?

Co-editor @catrinahacker.bsky.social explores in this week's post: pennneuroknow.com/2025/08/05/t...

#PsychSciSky #SciComm 🧠🟦 🧪 📖

As has been clear since April*, Vought intends a pocket rescission. This blanket hold is another tactic to maximize the size of that rescission. Rescission is THEFT from the public.

We have until Aug 15 to spend out the budget. CAL CONGRESS AND DEMAND THE HOLD BE LIFTED. Lives are on the line 🧪

*

Resolving a paradox about how vision is transformed into familiarity Simon Bohn, View ORCID ProfileCatrina M. Hacker, View ORCID ProfileBarnes G. L. Jannuzi, View ORCID ProfileTravis Meyer, Madison L. Hay, View ORCID ProfileNicole C. Rust While humans and other primates are generally quite good at remembering the images they have seen, they systematically remember some images better than others. Here, we leverage the behavioral signature of "image memorability" to resolve a puzzle around how the brain transforms seeing into familiarity. Namely, the neural signal driving familiarity reports is thought to be repetition suppression, a reduction in the vigor of the population response in brain regions including inferotemporal cortex (ITC). However, within ITC, more memorable images evoke higher firing rate responses than less memorable ones, even when they are repeated. These two observations appear to conflict: if reduced firing leads to stronger memory signaling, then why are the images that induce greater firing more memorable? To resolve this paradox, we compared neural activity in ITC and the hippocampus (HC) as two rhesus monkeys performed a single-exposure image familiarity task. We found evidence that the paradox is resolved in HC where neural representations reflected an isolated memory signal that was larger for more memorable images, but HC responses were otherwise uncorrupted by memorability. Memorability behavior could not be accounted for by trivial computations applied to ITC (like thresholding). However, it could be decoded from ITC with a linear decoder that corrects for memorability modulation, consistent with the hypothesis that ITC reflects familiarity signals that are selectively extracted through medial temporal lobe (MTL) computation. These results suggest a novel role for the MTL in familiarity behavior and shed new light on how the brain supports familiarity more generally.

⚡ New preprint ⚡ Long ago, I heard a talk about our remarkable ability to remember 1000s of images, after seeing each only once. How do brains manage it? 🤔

After years, this reflects the answer I was looking for. Congrats to Simon Bohn et al.

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

More: /1

My latest Aronov lab paper is now published @Nature!

When a chickadee looks at a distant location, the same place cells activate as if it were actually there 👁️

The hippocampus encodes where the bird is looking, AND what it expects to see next -- enabling spatial reasoning from afar

bit.ly/3HvWSum

Hemifield Specificity of Attention Response Functions during Multiple-Object Tracking The difficulty of tracking multiple moving objects among identical distractors increases with the number of tracked targets. Previous research has shown that the number of targets tracked (i.e., load)...

I am excited to announce (belatedly) that my dissertation’s final chapter has been published in the Journal of Neuroscience! doi.org/10.1523/JNEU...

Cephalopods, vision’s next frontier For decades, scientists have been teased by the strange but inaccessible cephalopod visual system. Now, thanks to a technological breakthrough from a lab in Oregon, data are finally coming straight…

The octopus brain has teased researchers since the 1960s, but recording from it seemed impossible. Cris Niell and his team’s calcium imaging experiments finally “showed that this brain could be studied,” says Sam Reiter.

By @callimcflurry.bsky.social

www.thetransmitter.org/vision/cepha...

New preprint! Statistical structure skews object memory toward predictable successors. Model simulations show how this bias can arise from the backward expansion of hippocampal representations.
w/co-first @codydong.bsky.social , @marlietandoc.bsky.social & @annaschapiro.bsky.social osf.io/yuxb6_v1

They would've found something to weaponize regardless. One of the most admirable things about science is its commitment to self-criticism. The fact that bad actors may capitalize on our legitimate concerns should never stop us from being honest and reflective about what we do.

Higher-level spatial prediction in natural vision across mouse visual cortex Theories of predictive processing propose that sensory systems constantly predict incoming signals, based on spatial and temporal context. However, evidence for prediction in sensory cortex largely co...

New preprint, w/ @predictivebrain.bsky.social !

we've found that visual cortex, even when just viewing natural scenes, predicts *higher-level* visual features

The aligns with developments in ML, but challenges some assumptions about early sensory cortex

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

Thank you @joulesriley.bsky.social for covering such an important topic!

Curiosity-driven research is essential, even when we're not certain exactly what application it might have down the line. The two examples Jules highlights show how investing in basic research now has huge payout later.

This highlights the point that comparisons between humans and machines are continually muddied by a lack of distinction between evolution and development, both of which contribute to learning in the broad sense.

Systems consolidation reorganizes hippocampal engram circuitry Nature - A study shows that loss of memory precision associated with systems consolidation can be explained by neurogenesis-dependent reorganization of engram circuitry within the hippocampus over...

Sharing a new paper from the lab. This paper, led by Sangyoon Ko, represents a merging of two longstanding research themes in the lab-- adult neurogenesis and systems consolidation.

rdcu.be/el18q

A short thread follows for those interested.

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(1/6) Thrilled to share our triple-N dataset (Non-human Primate Neural Responses to Natural Scenes)! It captures thousands of high-level visual neuron responses in macaques to natural scenes using #Neuropixels.

AI Changes Science and Math Forever | Quanta Magazine An exploration of how artificial intelligence is changing what it means to do science and math, and what it means to be a scientist.

In a new special series called “Science, Promise and Peril in the Age of AI,” @quantamagazine.bsky.social looks far beyond AI-based research tools to explore how #AI is changing what it means to do #science and what it means to be a scientist.
www.quantamagazine.org/series/scien...

Neural and behavioral signatures of policy compression in cognitive control Making context-dependent decisions incurs cognitive costs. Cognitive control studies have investigated the nature of such costs from both computational and neural perspectives. In this paper, we offer...

New work by @liushuze.bsky.social establishes an empirical link between policy complexity and neural dimensionality:
www.biorxiv.org/content/10.1...

Why does the forebrain expand dramatically while other neural regions grow less? Our new publication reveals progenitor metabolism critically shapes region-specific brain growth. Thread below. authors.elsevier.com/a/1k-udL7PXu...

Heterochronic transcription factor expression drives cone-dominant retina development in 13-lined ground squirrels. Evolutionary adaptation to diurnal vision in ground squirrels has led to the development of a cone-dominant retina, in stark contrast to the rod-dominant retinas of most mammals. The molecular mechani...

Our latest manuscript (7 years in the works) tackles the question of how diurnal ground squirrels evolved a cone-dominant retina, in contrast to the ancestral rod-dominant retina retained by virtually all other mammals./1
www.biorxiv.org/content/10.1...

🧠✨How do we rebuild our memories? In our new study, we show that hippocampal ripples kickstart a coordinated expansion of cortical activity that helps reconstruct past experiences.

We recorded iEEG from patients during memory retrieval... and found something really cool 👇(thread)

The representation of mood in primate anterior insular cortex Understanding how the brain reflects and shapes mood requires resolving the disconnect between behavioral measures of mood that can only be made in humans (typically based on subjective reports of hap...

A putative neural correlate of mood!

One big (scandalous?) idea, simple analyses, and the STRONGEST brain/behavior correlation I've EVER seen (which is shocking, given that it's mood).

Work with: You-Ping Yang, @catrinahacker.bsky.social and Veit Stuphorn.

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

Moreover, these funds serve the public interest. Universities do things private companies with research capacities cannot: train research talent, conduct basic research with uncertain payoffs, and distribute knowledge as a public good. And the rewards have been enormous. Everything from the internet to pharmaceutical and health care innovations evolved from such investments. We are richer and healthier for the investment.

The trope that universities are "dependent" on the federal government fundamentally misunderstands how vital this partnership has been for the US. The private sector can't replace it. If we kill it, we're all worse off. From @donmoyn.bsky.social and me: donmoynihan.substack.com/p/are-univer...

For the last 3 yrs, I was the director for the Science of Science program at the NSF. We funded projects on science communication - science communication to the public, communication of public priorities to scientists, citizens engagement & participation in science. 🧵

This work with Alan Stocker, @lingqiz.bsky.social, and Jiang Mao is now in print. We benefited from very thoughtful reviewers. www.pnas.org/doi/10.1073/...

I had so much fun writing this summary of awesome work done by @lizsiefert.bsky.social @annaschapiro.bsky.social and co.!

Learn about how your brain transforms memory during sleep (and at least one reason getting sleep is so important!): www.upennglia.com/briefs/bib-m...

#neuroskyence #SciComm 🧪

Experience reorganizes content-specific memory traces in macaques Memory formation requires neural activity reorganization during experience that persists in sleep. How these processes promote learning while preserving established memories remains unclear. We record...

How does the brain integrate information from new experiences while preserving established memories? Have a look at our latest preprint,
"Experience reorganizes content-specific memory traces in macaques" 🧵
🧪🧠🤖👩‍🔬
www.biorxiv.org/content/10.1...

Ack, thank you for catching that! I've corrected it in the post.

So far, this has continued into the 21st century. Between 2010 and 2019 NIH contributed to developing 354 of 356 newly-approved drugs, and in 2023 every $1 of NIH funding led to $2.46 in economic activity.

Research funding has a proven return on investment and deserves continued investment!

end

Among the many things I learned while writing the post, the history was especially impactful.

Over the 20th century, as the US invested increasingly more in biomedical research, average life expectancy increased 30 years, 25 of which can be attributed directly to advances in public health!

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In the face of threatened budget cuts, I wrote about how biomedical research is funded in the United States for this week's @pennneuroknow.bsky.social post.

Please share! I hope that this can be a resource to explain research funding to non-scientists and scientists alike.

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Individual variability of neural computations underlying flexible decisions - Nature Behavioural experiments to study decision-making in response to context-dependent accumulation of evidence provide testable models that are consistent with the heterogeneity in neural signatures among...

1/7 Our paper on individual variability in decision-making is finally out in @nature.com! Inspired by the classic work by Mante and Sussillo, we trained many rats to solve context-dependent decision-making, and we found that different brains use different neural mechanisms to solve the same task!

Falling back into old habits? Stress could be to blame! New work in mice reveals that stress dials back the ability to make thoughtful decisions and shifts the brain towards an “autopilot” mode that favors habits.

Ever found yourself falling back into old habits when you're stressed?

This week, @kara-mcgaughey.bsky.social breaks down new work in mice showing what brain circuits may be to blame: pennneuroknow.com/2025/03/18/f...

#neuroskyence #PsychSciSky #SciComm 🧪