This is beautiful work and quite the discovery. This also plays nicely with the idea that superficial place cells are rigid and deep are flexible. Seems to suggest that the flexibility is more about past rep's integrating with newer rep's, than the opposite.

The naturalist Jane Goodall died today at 91. Hope, she argued, is not merely “passive wishful thinking” but a “crucial survival trait.” Revisit a conversation with Goodall, from 2021: nyer.cm/F55JtsS

I’m pleased to share our new paper, “Hippocampal ripple diversity organizes neuronal reactivation dynamics in the offline brain”, out in @cp-neuron.bsky.social !

With @vitorlds.bsky.social and David Dupret, we show that diversity in ripple current profiles shapes reactivation dynamics

The Sosa Lab website is now live!
www.sosaneurolab.com

We will be seeking a postdoctoral researcher to join the growing team! If you are a rodent neuroscientist and interested in doing systems neuro work in the mountains 🏔️, please check out the "Join" page.

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🚨 New preprint! 🚨

Excited and proud (& a little nervous 😅) to share our latest work on the importance of #theta-timescale spiking during #locomotion in #learning. If you care about how organisms learn, buckle up. 🧵👇

📄 www.biorxiv.org/content/10.1...
💻 code + data 🔗 below 🤩

#neuroskyence

Proud to take on this challenge: building the new Centro de Neurociencias Cajal @institutocajal.bsky.social into a space where neuroscience crosses boundaries and transforms how we understand the 🧠!!

Going to open an escape room where hippocampus researchers have to solve riddles without using space as an explanation for everything

Our collaboration - from PhD work - examining input-specific (EC L3) contributions to rate and temporal coding in CA1 place cells is now out in @natcomms.nature.com 🔬🧠

rdcu.be/evWtz

I know it’s popular to think of citations as attribution of credit, but a part of me also likes to think of them as a trail of fun breadcrumbs for someone 20 years in the future.

this heat map study of gender differences of walking through urban environments at night is not surprising, but still sort of incredible to see

news.byu.edu/intellect/st...

It's so heartbreaking to see one of the 'three angry old men'* flirting w the idea of bombing a country so nonchalantly.

Like 90million ppl are at the mercy of the 'noise' in his drift diffusion process--is it accumulating to this bound or that bound😞

*see this: www.theguardian.com/commentisfre...

It's officially published!! In my main postdoc work with @markplitt.bsky.social and @lgiocomo.bsky.social, we found that the hippocampus simultaneously encodes an animal's spatial position and its experience relative to reward in parallel population codes. 🧵

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

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

Thank you Sanja!

The embedding enables a cool experiment: start with a tetrode in CA1 pyr, lower it gradually, and project the signal at each step.
The tetrode follows the predicted path, and the gamma profiles match the silicon probe data beautifully at each step.
See one going from CA1 pyr to DG midmol below!

If you're interested in the code, see: github.com/vitorlds/Hip...
I’ll be updating it soon with a newer Python version and more data!

(13/13)

Overall, I had a lot of fun preparing this manuscript.
It started as a side project to support various experiments in the lab, but it grew into its own thing.
Huge thanks to Demi and David for working with me on this at @mrcbndu.ox.ac.uk, and to our reviewers for helping improve the paper.
(12/13)

In short: LFPs carry rich circuit information.
We mapped oscillations and neuronal firing across CA1–DG layers.
This opens new doors for identifying oscillations, circuit motifs, and homogenize layer identification across datasets.
Check out the paper: doi.org/10.1016/j.ce...

(11/13)

Using optogenetics, we tested how CA1 interneurons across layers respond to upstream input.
CA3 terminal stimulation strongly activated pyramidale (PyrInt) and radiatum (rad) interneurons, while EC terminal stimulation strongly drove LM interneurons.

(10/13)

Using embedding-guided tetrodes, Demi recorded interneurons in sparse CA1 layers: rad and LM (btw great dataset, stay tuned for future work on this!).
Firing behavior was layer-specific; e.g., LM interneurons were barely active in ripples.
Preferred theta phase also varied across layers.

(9/13)

I love this figure
By projecting tetrode LFPs from several mice onto the embedding (estimating each tetrode’s “depth”), we recover gradually changing theta and ripple waveforms, as if recorded with a single linear probe.
No need for alignment or histology. Just the signals and the embedding.

(8/13)

Zooming in, the embedding also separates deep vs superficial CA1 pyramidal cells.
These groups differ in firing rates (awake and sleep), theta modulation, and coupling to gamma and ripple.
This let us replicate findings from fancy silicon probes using tetrodes, and extend them further.

(7/13)

From our spike analysis:
In pyr fast gamma, principal cells fire before interneurons. In rad fast gamma, this flips!
Same freq range, but ≠ mechanism.
+ pyr fast gamma and ripples may arise from the same oscillator: called 'fast gamma' when theta-driven, 'ripples' when driven by SW inputs.

(6/13)

Histological validation: lower tetrodes along the CA1–DG axis until they reach a target layer, then confirm final position with histology.
It’s really robust! Ephys patterns do predict anatomical layers.
See two tetrodes going to DG molecular layer below (more examples in the paper!).

(5/13)