Alexandra Keinath

We'll be missing you too, David!

Screenshot of the top of the article, including the title, authors, and abstract.

What’s better than a one-channel #Miniscope? 🥁 A TWO-CHANNEL Miniscope!

Our new Miniscope2C is a dual-channel, open-source Miniscope that lets you record 2 fluorescent signals simultaneously in freely moving animals.

Read the paper here: www.science.org/doi/10.1126/...

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6\. Really excited about these results and about how this approach can be used in the future! Lots more to do, but I think these comparisons of rep geometry across assays can really help us add more nuance to our understanding of similarities and differences between species (and other comparisons).

5\. Does the difference between these assays depend on the human visual advantage? In another cohort of participants, we demonstrate that masking the visual world with dense fog during retrieval does NOT impact representational geometry or cross-species resemblance. So it’s not just about vision!

4\. Does this depend on the scale of the environment? We repeated our experiment in a room double the size (5x5 vs. 10x10 m). Here, the local impact of deformations scaled up, in turn preserving the rep geometry and cross-species resemblance. So it's not just about scale (at least for the humans)!

3\. The geometry of human memory is similar but not the same as mouse CA1. Instead, it resembles a change-resistant version. CA1 subpopulations with higher firing rates, stability, and spatial specificity look more human-like. Low precision (but not low accuracy) memories look more mouse-like.

2\. We then compare the geometry of these reps to those of mouse CA1 recorded during analogous deformations, leveraging a dataset that @markbrandonlab.bsky.social‬, @jquinnlee.bsky.social‬, and I published recently. (Check out that work if you haven’t already! www.cell.com/neuron/fullt....

1\. We use immersive VR to characterize the impact of a diverse deformations on human spatial memory. Across 3 experiments of 100+ participants each, we find that deformations induce compounding local distortions in memory.

Change-resistance distinguishes the representational geometries of human spatial memory and mouse CA1 in deformed environments Prior work has highlighted qualitative similarities between the neural instantiations of cognitive maps in rodents and memory-guided navigation in humans, suggesting a conservation of representational...

Trans rights are human rights.

Fresh work incoming: Here we quantitatively compare the representational geometry of mouse CA1 and human spatial memory during environmental deformations. Briefest TLDR: Human memory looks like a change-resistant version of mouse CA1.

www.biorxiv.org/cgi/content/...

Gotta make sure your results generalize to mascots! #uic

Super excited to share that one of our outstanding founding undergrad RAs @dahery.bsky.social will be headed to the Kempner postbac program at Harvard to work with @gershbrain.bsky.social after graduation! Congratulations David! You cannot be replaced, and I’m so proud and excited for you!

The dataset and code for our recent paper in Neuron (tinyurl.com/yc48d6vr) is online now!
The data is available on Zenodo (zenodo.org/records/1486...) and code on Github (github.com/jquinnlee/ge...). Big thanks to @markbrandonlab.bsky.social and @atkeinath.bsky.social on this effort! #neuroskyence 🧠

How good is your place cell model?

Come benchmark yours against real data - nearly 70K CA1 rate maps in various geometric shapes across weeks - collected and curated in my lab by the great @jquinnlee.bsky.social and @atkeinath.bsky.social

The Young, Inexperienced Engineers Aiding Elon Musk's Government Takeover Engineers between 19 and 24, most linked to Musk’s companies, are playing a key role as he seizes control of federal infrastructure.

If you’ve been wondering what Elon Musk and his lackeys are up to since taking control of the US government, look no further. Our latest story names six 19- to 24-year-olds working with his DOGE organization, which now has access to sensitive federal systems. wrd.cm/4jzpiSN

Shoutout to all the millennial junior faculty who finally got their dream jobs right as the scientific enterprise in the states is functionally dismantled.

i think an important thing for people outside the US to understand is that elon musk seized control of the government today and most americans don’t even realize it happened.

Map of london with the planned routes of 43 taxi drivers overlaid in yellow lines.

🚨 new publication from our lab in @pnas.org !
"Expert navigators deploy rational complexity–based decision precaching for large-scale real-world planning"

Entropy of streets & successor representations explain planning speed

Colab wth Daniel McNamee at Champalimaud

www.pnas.org/doi/10.1073/...

White House pauses all federal grants, sparking confusion The Trump administration has put a hold on all federal financial grants and loans, affecting tens of billions of dollars in payments.

Trump is attempting to unilaterally freeze trillions of dollars in federal spending that’s been duly appropriated by Congress. This is completely insane and illegal. He’s seizing unlawful control over the constitutional spending power? Five alarm fire www.washingtonpost.com/business/202...

RFkJr is a threat to human health: when the next pandemic hits we need disease tracking (CDC now silenced) and fast vaccine development (which he opposes). If you live in ME, NC, SD, LA, AK, ID, KY or SD call your senators to oppose his confirmation (hearing this Wed.).
(continued, please retweet):

This is a very scary time for early career scientists like people looking for/who are postdocs and new faculty trying to get funding. Any words of encouragement to share for people in this category?

Human hippocampal CA3 uses specific functional connectivity rules for efficient associative memory Human hippocampal CA3 networks use sparse and broad synaptic connectivity, and their recurrent synapses employ reliability, precision, and long integration times to enhance memory capacity. Thus, the ...

Okay, this is very cool: evidence from Peter Jonas' group that human CA3 follows a different logic of synaptic connectivity than rodent CA3, focussing more on sparser, but highly reliable synapses.
www.cell.com/cell/fulltex...

CC @dlevenstein.bsky.social & @repromancer.bsky.social

#neuroscience 🧪

It’s real rn!

Can’t wait Andy! Definitely stoked to catch up!

Tough week to be a trans neuroscientist with an immigrant spouse in the US…

… anyway, see y’all at Winter Brain!

A cellular basis for mapping behavioural structure - Nature Mice generalize complex task structures by using neurons in the medial frontal cortex that encode progress to task goals and embed behavioural sequences.

Out now in Nature from @behrenstimb.bsky.social and crew:

www.nature.com/articles/s41...

Understanding this kind of schematic pattern learning and transfer will be key, IMO, to moving towards models of what we might call "higher-order cognition" or "reasoning".

🧠📈 🧪

Thanks Q! And thanks for your feedback on the draft! :)

Looks like a Friday to me!

Great Q (@dahery.bsky.social brought this up in lab meeting)! We can't rule this out during the free navigation experiment, but the finding that changing navigation (while keeping geo constant) changes CA1 in a directional and transient way is harder to account for from a purely geo theory.

Yes! Literally the first name I searched for when I got this account haha. She was a staple of my neuro twitter!