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Peter Rupprecht

@ptrrupprecht.bsky.social

Junior group leader in neuroscience - calcium imaging, ephys, plasticity, microscopy, neurons & astrocytes, data analysis. PhD with Rainer Friedrich, postdoc with Fritjof Helmchen. https://www.gcamp6f.com/

676 Followers  |  585 Following  |  90 Posts  |  Joined: 02.10.2023  |  2.0367

Latest posts by ptrrupprecht.bsky.social on Bluesky

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A new preprint introduces aDISCO, a DISCO-based clearing approach that makes whole archival FFPE human tissues transparent and antibody-compatible, enabling true 3D light-sheet histology across brain & multiple organs at cellular resolution. Aguzzi & Helmchen teams.
www.biorxiv.org/content/10.1...

08.02.2026 19:41 β€” πŸ‘ 37    πŸ” 12    πŸ’¬ 0    πŸ“Œ 1
subthreshold depolarization before a complex spike correlates with local calcium during the complex spike.

subthreshold depolarization before a complex spike correlates with local calcium during the complex spike.

But then where do the branch-specific variations in voltage come from? We found that in apical dendrites, small subthreshold depolarizations *preceding* a complex spike partially predict voltage (and Ca2+) amplitude *during* the event. This suggests conjunctive amplification of inputs and spikes.

21.01.2026 19:50 β€” πŸ‘ 8    πŸ” 1    πŸ’¬ 1    πŸ“Œ 1
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What's the relation between voltage and calcium in dendrites? Xiang Wu studied this in CA2 hippocampal pyramidal cells in behaving mice. www.biorxiv.org/content/10.6...

21.01.2026 19:50 β€” πŸ‘ 58    πŸ” 17    πŸ’¬ 1    πŸ“Œ 0

Many more details and analyses, on cell-type effects in astrocytes, pyramidal cells and interneurons during arousal versus optogenetic LC stimulation: www.biorxiv.org/content/10.6...
Huge congrats to Sian on her beautiful PhD work! 5/5

19.01.2026 13:36 β€” πŸ‘ 3    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Example of activity traces obtained from calcium imaging for interneurons during natural arousal and artificial arousal (LC stimulation) across days.

Example of activity traces obtained from calcium imaging for interneurons during natural arousal and artificial arousal (LC stimulation) across days.

A subpopulation of interneurons is directly activated by LC activation. Those interneurons are preferentially located in specific CA1 laminae. 4/5

19.01.2026 13:36 β€” πŸ‘ 3    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
Example of activity traces for astrocytes during natural arousal and artificial arousal (LC stimulation) across days.

Example of activity traces for astrocytes during natural arousal and artificial arousal (LC stimulation) across days.

Several interesting observations along the way. For example, astrocytes show diverse sensitivities to LC stimulation, variable across cells but consistently for each cell. 3/5

19.01.2026 13:36 β€” πŸ‘ 3    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
Scheme illustrating the central finding: LC stimulation vs. natural arousal elicit distinct cellular responses across cell types.

Scheme illustrating the central finding: LC stimulation vs. natural arousal elicit distinct cellular responses across cell types.

Our main finding is that natural arousal and optogenetic LC stimulation elicit strikingly distinct responses at the single-cell level. 2/5

19.01.2026 13:36 β€” πŸ‘ 3    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Excited to share our new preprint! We explore the link between the locus coeruleus (LC) and arousal for astrocytes, pyramidal cells, interneurons in the hippocampus. A fantastic collaboration with @sianduss.bsky.social @bohaceklab.bsky.social, and many others: www.biorxiv.org/content/10.6... 1/5

19.01.2026 13:36 β€” πŸ‘ 63    πŸ” 20    πŸ’¬ 1    πŸ“Œ 1

What I meant is that a smart PDF reader could generate/guess the abbreviations, without any need to hard-code them for each instance of an abbreviation.

16.01.2026 22:53 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Google Scholar PDF Reader - Chrome Web Store Supercharge your paper reading: follow references, skim outline, jump to figures, cite and save.

Great idea, but works only with LaTeX. Maybe best to implement it via the *PDF reader*, not the PDF. Some browser addons for reading PDFs do this already by linking figure refs and citations (chromewebstore.google.com/detail/googl...)
Adding the same feature for abbreviations should be feasible.

16.01.2026 22:40 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

That's a very interesting approach! What happens if you select the 10-20 best quadruplet rules and select neurons/synapses randomly from these rules? Wouldn't this diversity make the network/neuron more stable and capable? Curious about your take.

15.01.2026 12:47 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

But from a scientific perspective, your approach (modeling first, then data analysis) seems absolutely valid to me!

12.01.2026 14:26 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

In a paper, mixing modeling, data analysis and experiments may be more difficult to browse and follow for the average reader. In systems neuroscience, we are used to seeing first the data analysis and then - in the final figure - a model (which can be ignored by those who don't understand it).

12.01.2026 14:25 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 2    πŸ“Œ 0

Still have to read it carefully with all methods and details, but it's a candidate for my favorite paper of 2026! Very cool, and important work to understand how neurons and dendrites work!

06.01.2026 17:54 β€” πŸ‘ 9    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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Annual report of my intuition about the brain (2025, part III) How does the brain work, and how can we understand it? To approach this big question from a broad perspective, I want to report on someΒ ideasΒ about the brain that marked me most over the …

What would it really mean to achieve experimental goals that currently seem out of reach: a new blog post.

Part III - Simultaneously recording from all neurons of the human brain
gcamp6f.com/2026/01/03/a...

06.01.2026 17:49 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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Annual report of my intuition about the brain (2025, part III) How does the brain work, and how can we understand it? To approach this big question from a broad perspective, I want to report on someΒ ideasΒ about the brain that marked me most over the …

What would it really mean to achieve experimental goals that currently seem out of reach: a new blog post.

Part II - Recording the inputs and the output of a single neuron in real time in vivo
gcamp6f.com/2025/12/30/a...

06.01.2026 17:47 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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Annual report of my intuition about the brain (2025, part I) How does the brain work, and how can we understand it? To approach this big question from a broad perspective, I want to report on someΒ ideasΒ about the brain that marked me most over the …

What would it really mean to achieve experimental goals that currently seem out of reach: a new blog post.

Part I - connectomics
gcamp6f.com/2025/12/27/a...

06.01.2026 17:45 β€” πŸ‘ 7    πŸ” 1    πŸ’¬ 2    πŸ“Œ 0

New preprint from the lab! πŸš€
We find that hippocampal OLM interneurons provide a circuit-level inhibitory feedback signal that dynamically controls when and where behavioral timescale synaptic plasticity can occur.
Feedback welcome!

05.01.2026 15:11 β€” πŸ‘ 31    πŸ” 11    πŸ’¬ 0    πŸ“Œ 1
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What is the computational role of dendritic excitations? Byung Hun Lee and team mapped voltage dynamics throughout the dendritic trees of CA1 pyramidal neurons in mice navigating in virtual reality. www.biorxiv.org/content/10.6...

04.01.2026 06:17 β€” πŸ‘ 130    πŸ” 50    πŸ’¬ 3    πŸ“Œ 3

All the work by @colah.bsky.social (blog posts, distill etc.) is amazing - clear and transparent, with little or no jargon, trying to address the hard problems head-on.

16.12.2025 11:50 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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Dirigo: a future Python alternative to Scanimage? Over the last 20 years, many microscopes that are capable of resonant scanning two-photon microscopy have converged on using ScanImage, a powerful software package with many strengths but also two …

Thankful for this blog piece by @ptrrupprecht.bsky.social on the Dirigo project. Glad you liked the posts!
gcamp6f.com/2025/11/14/d...

21.11.2025 16:24 β€” πŸ‘ 7    πŸ” 3    πŸ’¬ 0    πŸ“Œ 0

But I believe that post-publication reviews, or the suggestions that you've made, or simply transparent open reviews, which is used by many journals already, are a good way to read papers better and more efficiently. And this is a culture change that has already taken place during the last decade...

21.11.2025 10:39 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

I don't think there is a way around properly reading the literature. How could we design science experiments, if the knowledge that we need for their design is somewhere in a database or LLM, but not in our heads?

21.11.2025 10:38 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
Peeriodicals Theory of spike initiation, sensory systems, autonomous behavior, epistemology

Good point! But already now, everybody can contribute to post-publication peer review right now, no need for a centralized structure. I regularly write such reviews on my blog: gcamp6f.com/category/rev...
The idea is not new, see the "peeriodicals" by Romain Brette:
peeriodicals.com/peeriodicals...

20.11.2025 20:59 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Independent NeuroScience Services INSS was registered as a company on 14th November 2016, which means it's our 9th birthday today! As a birthday present we've treated ourselves to an SfN exhibitor booth for the first time ever. Come and say hello at Booth #3327

15.11.2025 00:03 β€” πŸ‘ 10    πŸ” 5    πŸ’¬ 2    πŸ“Œ 1

If you don't learn how to write, then you don't learn how to think.

15.11.2025 15:52 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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Interesting papers on astrocyte ultrastructure and function Astrocytes are brain cells that are often completely overlooked and dismissed or, in the opposite extreme, presented as mysterious devices that somehow solve all problems of computational neuroscie…

New blog post, where I highlight a few interesting papers on astrocyte ultrastructure and function, with papers from the labs of Moritz HelmstΓ€dter @mhlab.bsky.social, Kristen Harris, Andrea Volterra, Karin Pernet-Gallay, and Hailan Hu: gcamp6f.com/2025/11/14/i...

14.11.2025 12:27 β€” πŸ‘ 9    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0
Jay’s Adapt~O~Matic – BrainRight

How did I not know about this super-useful site for customized 3D-printable thread adapters? HT to @leon-kremers.bsky.social : brainright.com/adapt-o-matic/

05.11.2025 11:02 β€” πŸ‘ 6    πŸ” 3    πŸ’¬ 1    πŸ“Œ 0
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The long wait is finally over: The @thorlabs.bsky.social 8 kHz resonant scanner is available πŸ”¬! It would be lovely if there would be a 30 mm cube compatible & acoustically shielded mount as well, but I'm sure that's going to come eventually! #Microscopy www.thorlabs.com/newgrouppage...

22.10.2025 18:47 β€” πŸ‘ 17    πŸ” 3    πŸ’¬ 2    πŸ“Œ 0

Looks like a 1:1 copy of the Cambridge Technology 8 kHz scanner. Did you notice any differences? Or have they simply licensed the technology from the existing scanner?

22.10.2025 19:58 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

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