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Reposted by Christoph Miehl

Science Vs @sciencevs.bsky.social · 7d

This moment from our latest episode with science writer @edyong209.bsky.social is 🔥

We asked Ed — how do we talk up the benefits of science in the face of government cuts? He told us that's the wrong approach. 🧪

Listen wherever, or watch on Spotify 👇

open.spotify.com/episode/7Evh...

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Reposted by Christoph Miehl

Ting-Feng Lin @tingfenglin.bsky.social · 13d

Hi #Neuroscience,
Exciting news—I’m recruiting a PhD student to join my lab and study neuroscience in larval zebrafish 🧠🐟
Microscopy expertise is a big plus!
Link: drive.google.com/file/d/1Wb4h...

NeuroPhD vacancy FoS - TFL2025.pdf

drive.google.com

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Reposted by Christoph Miehl

Prof John O Brennan @jobmaynooth.bsky.social · Aug 29

The best piece I’ve read this year on Trump’s increasingly blatant lurch towards total power.

To quote Sinclair Lewis, if you think “it can’t happen here” you are just not paying attention.
www.theguardian.com/commentisfre...

Step back and take it in: the US is entering full authoritarian mode | Jonathan Freedland

Trump’s dictator-like behaviour is so brazen, so blatant, that paradoxically, we discount it. But now it’s time to call it what it is, says Guardian columnist Jonathan Freedland

www.theguardian.com

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Reposted by Christoph Miehl

Mora Ogando @moraogando.bsky.social · Aug 5

Thrilled to share our new Adesnik lab paper!!
Using holography in excitatory & inhibitory neurons, we reveal how a single cortical circuit can both complete and cancel predictable sensory activity, sharpening representations
📄https://www.biorxiv.org/content/10.1101/2025.08.02.668307v1
🧵

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Reposted by Christoph Miehl

Flor Iacaruso @flor-iacaruso.bsky.social · Aug 1

1/N What are the organizational principles underlying crossmodal cortical connections?
We address this in this new preprint, led by @alexegeaweiss.bsky.social & ‪@bturner-bridger.bsky.social‬ in collab w/ ‪@petrznam.bsky.social‬ @crick.ac.uk
www.biorxiv.org/content/10.1...

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Christoph Miehl @cmiehl.bsky.social · Jul 28

I have heard about it, but I am not sure about the connection to our model. Could you share some papers with me that you think might be relevant? Thanks!

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Christoph Miehl @cmiehl.bsky.social · Jul 25

Thank you!
Yes, exactly, the idea is that (in cortex) the VIP-SST disinhibitory pathway gates plasticity at the dendrites, while PVs stabilize the activity of E cells. We have a paragraph about this with more details in the Discussion section of the manuscript.

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Reposted by Christoph Miehl

Julijana Gjorgjieva @gjorjulijana.bsky.social · Jul 25

Very happy to share this preprint from the lab led by @cmiehl.bsky.social, Sebastian and Maurycy on how to flexibly learn with nonlinear dendrites and inhibitory context-dependent gating, putting biological detail in ANNs. Check out Christoph's post below for a preview or the paper for more details!

Christoph Miehl @cmiehl.bsky.social · Jul 25

Excited to share our new preprint in which we propose a biologically plausible mechanistic solution to the problem of how the brain can flexibly learn and store new representations without forgetting previously learned information.

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

Detailed 🧵 below 👇 1/12

Assembly-based computations through contextual dendritic gating of plasticity

Neuronal assemblies — groups of strongly connected neurons — are considered the basic building blocks of perception and memory in the brain by encoding representations of specific concepts. Despite re...

www.biorxiv.org

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Christoph Miehl @cmiehl.bsky.social · Jul 25

This work has been co-led by Sebastian Onasch and me, with help from M. Maurycy Miękus under the guidance of @gjorjulijana.bsky.social.
Thanks to our funding sources @erc.europa.eu and @hfspo.bsky.social!

If you have questions/feedback, don’t hesitate to contact us! 12/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

In conclusion, we introduce new avenues for performing assembly computations with biologically inspired mechanisms, demonstrating flexible learning and combining of assemblies without forgetting, bridging the gap between biological realism and computational functionality in circuit modeling. 11/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

We show that in hierarchically connected areas, assemblies enhance recall & pattern completion in downstream areas, despite disruptions in previous areas.
Finally, we show how our model allows for learning of associations with existing assemblies, another key concept for flexible learning. 10/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

We designed a visual-auditory association task to demonstrate the applicability of this ‘assembly calculus’ framework in a real-world example. Our model can correctly classify letters and numbers in a downstream concept area, even if only part of the sensory information is presented. 9/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

We next investigated how the formed assemblies can be combined across areas. We focus on two assembly operations – projections and associations. In short, these operations can be learned across areas – importantly without any decay (forgetting) of previously learned structures. 8/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

In a recurrent network with 400 multi-compartment neurons, switching one inhibitory context “on” allows for learning of stable dendrite-specific assemblies at disinhibited dendritic compartments. 7/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

Assuming that inhibitory (sub-) populations encode “context” signals controlling distinct dendritic compartments, inhibitory neurons can flexibly gate plasticity on or off at each specific dendritic compartment. 6/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

We use a multi-compartment neuron model with a spiking soma in which synapses at the dendrites undergo voltage-dependent synaptic plasticity. Here, the balance of excitatory and inhibitory inputs at each dendrite determines the sign and amount of plasticity. 5/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

We propose a biological plausible model, combining nonlinear dendrites and inhibitory context-dependent gating to enable flexible learning without forgetting. Our model bridges scales from dendritic properties to assembly learning in recurrent circuits to multi-area assembly computations. 4/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

At the same time, artificial neural networks (ANNs) have proven successful in performing a diversity of tasks and computations. However, they mainly rely on assumptions that are not biologically plausible and suffer from the problem of catastrophic forgetting. 3/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

A prominent hypothesis suggests that groups of neurons (assemblies) provide the basis of perception/memory in the brain. Previous studies often fall short in showing how assemblies can be flexibly learned and combined to perform complex computations without forgetting previously learned ones. 2/12

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Christoph Miehl @cmiehl.bsky.social · Jul 25

Excited to share our new preprint in which we propose a biologically plausible mechanistic solution to the problem of how the brain can flexibly learn and store new representations without forgetting previously learned information.

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

Detailed 🧵 below 👇 1/12

Assembly-based computations through contextual dendritic gating of plasticity

Neuronal assemblies — groups of strongly connected neurons — are considered the basic building blocks of perception and memory in the brain by encoding representations of specific concepts. Despite re...

www.biorxiv.org

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Christoph Miehl @cmiehl.bsky.social · May 28

Wait, what???

Michael Clemens @mclem.org · May 27

The US Administration has indefinitely blocked *all* student visa applicants from getting a visa interview.

Worldwide, unconditional, no end date. All.

International students are crucial to the US university system, American innovation, and future US prosperity.

Rubio Reportedly Pauses New International Student Visa Interviews

More than 1.1 million international students were enrolled at U.S. colleges and universities in the 2023-2024 school year.

www.forbes.com

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Reposted by Christoph Miehl

Hayley Bounds @hayleybounds.bsky.social · May 15

Excited to share my PhD paper! In it, we use targeted 2-photon optogenetic stimulation to determine how V1 activity is read-out in a detection task. We found that network influence, not visual coding properties, predicted the impact of ensembles on behavior - contradicting our expectations (1/5).

Neuron @cp-neuron.bsky.social · May 15