Peter Rupprecht

It's a great paper - congrats!

This objective was designed for 2P imaging. For 1P imaging, I believe that there are still some technical problems to be solved. Perhaps @voigtvision.bsky.social or @nvladimus.bsky.social can tell you more!

I'm using it mostly for 2P imaging, but it should also be relevant for expansion microscopy: Olympus XLPLN10XSVMP with NA 0.6, WD 8 mm: evidentscientific.com/en/objective...

Reflective multi-immersion microscope objectives inspired by the Schmidt telescope - Nature Biotechnology Imaging of large, cleared samples in diverse media is achieved using a mirror objective.

Reflective Schmidt objectives with high NA and long WD: www.nature.com/articles/s41...
@voigtvision.bsky.social

EPFL-Smart-Kitchen-30: Densely annotated cooking dataset with 3D kinematics to challenge video and language models Understanding behavior requires datasets that capture humans while carrying out complex tasks. The kitchen is an excellent environment for assessing human motor and cognitive function, as many complex...

Understanding behavior requires datasets that capture humans while carrying out complex tasks. The kitchen is an excellent environment for assessing human motor and cognitive function, as many complex actions are naturally exhibited in kitchens from chopping to 🧽!

arxiv.org/abs/2506.01608

« Diverse calcium dynamics underlie place field formation in hippocampal CA1 pyramidal cells. »

A fundamental study now published @elife.bsky.social

elifesciences.org/reviewed-pre...

Displaying the hippocampus as EM image on the office wall One of the most amazing methods in modern neuroscience is dense volumetric electron microscopy of the brain. I have mentioned some openly accessible datasets before (see my previous blog post), but…

New blog post about a fun project where I tried to beautify my office by putting a poster of the hippocampal column onto my walls: gcamp6f.com/2025/08/13/d...
EM pictures from this paper: www.biorxiv.org/content/10.1... from the lab of @helenelab.bsky.social

Interesting papers on the role of cell organelles in neuronal dendrites for calcium signaling Researchers utilize calcium imaging to track neuronal activity in the brain, highlighting the role of calcium as a signaling molecule. Recent studies investigate intracellular calcium dynamics, par…

New blog post, where I review some recent interesting papers on the role of cell organelles for neuronal calcium signaling: gcamp6f.com/2025/08/11/i...
Featuring work by @lorenabenedetti.bsky.social, O'Hare et al. and Lin et al.!

I also wonder whether you have observed any signs of cytotoxicity or fluorophore aggregates?

This OCaMP sensor looks quite promising! Looking forward to trying it out!

A sensitive orange fluorescent calcium ion indicator for imaging neural activity Genetically encoded calcium indicators (GECIs) are vital tools for fluorescence-based visualization of neuronal activity with high spatial and temporal resolution. However, current highest-performance...

#OCaMP is now on bioRxiv and reagents are available on #Addgene! 🧪

A sensitive orange fluorescent calcium ion indicator for imaging neural activity

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

Thanks, it looks very interesting!

The first comment of reviewer #1 is also "interesting", asking for the "connectome" of VIP neurons for the revised manuscript ;-)

New blog post with a review of interesting papers on VIP interneurons in cortex and hippocampus: gcamp6f.com/2025/06/23/i...
Covering work from @koenvervaeke.bsky.social's lab with @mateneubrandt.bsky.social, Yoav Adam's lab and Bernardo Rudy's lab.

Brightly labelled pyramidal cells in the mouse retrosplenial cortex. Blood vessels are visible of various thicknesses in darker colours.

#neuroskyence folks: as my postdoc grant is running out soon, I am looking for new opportunities in systems neuroscience!

Keywords: patch clamp ephys, opto, mouse behavior, (in vivo) voltage imaging. Would love to return to the Basal Ganglia.

Sharing appreciated, and happy #FluorescenceFriday !

Three-photon in vivo imaging of neurons and glia in the medial prefrontal cortex with sub-cellular resolution - Communications Biology Three-photon in vivo imaging provides access to medial prefrontal cortex, hippocampus and spinal cord in mice at up to 1.7 mm depth of neurons, dendrites, spines, astrocytes and microglia.

It is out! Read how you achieve 1.7 mm deep 3-photon imaging in prefrontal cortex with dendritic spine resolution over a week.
www.nature.com/articles/s42...

1/6 Why does the brain maintain such precise excitatory-inhibitory balance?
Our new preprint explores a provocative idea: Small, targeted deviations from this balance may serve a purpose: to encode local error signals for learning.
www.biorxiv.org/content/10.1...
led by @jrbch.bsky.social

Yes, this is great work! An important aspect is that it clearing of *archival* FFPE tissues over 10 years old. This method suddenly makes such biomedical archives much more valuable.

The culmination of years of hard work by Anna Maria Reuss & Co: aDISCO - a protocol for clearing & antibody-staining human formalin-fixed paraffin-embedded (FFPE) tissue! With lots of @mesospim.bsky.social #lightsheet #Microscopy @ptrrupprecht.bsky.social & many more!
www.biorxiv.org/content/10.1...

Could it also be feedback inhibition?

Introducing warpfield, an open source Python library for GPU-accelerated non-rigid 3D registration. Warps and aligns gigavoxel volumes within seconds (not hours). For 3D microscopy, region-to-region and cell-to-cell matching.
A collaboration with @mh123.bsky.social 🚀
github.com/danionella/w...

Spike Rate Inference from Mouse Spinal Cord Calcium Imaging Data Calcium imaging is a key method to record the spiking activity of identified and genetically targeted neurons. However, the observed calcium signals are only an indirect readout of the underlying elec...

Our study on spike inference from calcium imaging data in spinal cord is now published at the Journal of Neuroscience @sfnjournals.bsky.social ! 🥳With open datasets and public reviews: www.jneurosci.org/content/45/1...

Thanks! I knew this one and was curious about hippocampus-specific astrocytes. But I'll check the paper again!

(at least it's not possible in the recordings that I'm aware of)

Yes, I believe it's hard. There are only some dozen people in who could do these in vivo whole-cell recordings. In addition, in vivo there are so many EPSPs that you cannot detect single ones. It is currently not possible to reliably detect individual EPSPs in in vivo recordings.

The work of David McCormick (e.g., doi.org/10.1146/annu...) goes into this direction, but maybe this deviates already too much from your original question ;-)

Whether these neuromodulatory effects on neurons affect EPSP amplitude, excitability or something else is difficult to know - it would require whole-cell recording in the living animal while controling the neuromodulators.

I would assume that blood flow is partially controlled by local spiking activity (as mentioned by Luke), and less so the other way around (blood flow causing additional spikes). However, neuromodulation (NA or ACH, which also control vasoconstriction) act as a gain modulator for neuronal spiking.

I believe it is still an open question how or whether neuromodulatory effects are specific, thereby potentially resulting in vessel dilation in a specific part of cortex but not in another.

To provide (or replenish) energy, blood vessel dilation seems the most obvious candidate. Vessel dilation is controlled by neuromodulators like NA or ACh directly, or indirectly by the endfeet of astrocytes (which respond to NA or ACh), e.g. www.biorxiv.org/content/10.1...

And another question: Do you have advice on how to identify astrocytes from this stack? So, if I just scroll through the raw data, would I be able to identify them based on the coarse somatic region?