Excited to share a new review by @kocherlab.bsky.social and me:
Nature-inspired neuroscience
We discuss diverse sensory systems and behaviors across the animal kingdom and argue for their integration into neuroscience. New tools in diverse systems are making this possible ✨
tinyurl.com/y5y9du27
The supply of blood to brain tissue is thought to depend on the overall neural activity in that tissue, and this dependence is thought to differ across brain regions and across brain states. However, studies supporting these views have measured neural activity as a bulk quantity and related it to blood supply following disparate events in different regions. Here we measure fluctuations in neuronal activity and blood volume across the mouse brain, and find that their relationship is consistent across brain states and brain regions but differs in two opposing brainwide neural populations. Functional ultrasound imaging (fUSI) revealed that whisking, a marker of arousal, is associated with brainwide fluctuations in blood volume. Simultaneous fUSI and Neuropixels recordings showed that neurons that increase activity with whisking have distinct haemodynamic response functions compared with those that decrease activity. Their summed contributions predicted blood volume across states.Brainwide Neuropixels recordings revealed that these opposing populations coexist in the entire brain. Their differing contributions to blood volume largely explain the apparent differences in blood volume fluctuations across regions. The mouse brain thus contains two neural populations with opposite relations to brain state and distinct relationships to blood supply, which together account for brainwide fluctuations in blood volume.
How does blood flow relate to brain activity? We discovered that it reflects two neural populations affected oppositely by arousal. Together, they explain neurovascular coupling in all brain regions and brain states!
Out today in Nature: rdcu.be/fdC2A
@uclbrainscience.bsky.social
New preprint, on a very different topic: a mathematical theory of evolution for self-designing AI.
AI is increasingly designed by AI. What systems might emerge after generations of self-designing AIs competing for computing resources? ↓
arxiv.org/abs/2604.05142
Want to explore connectivity & projection patterns yourself, like we do here? We released brain_street_view to let you pick any injection site in the Allen Connectivity Atlas and visualize where it projects in your favorite region of interest: github.com/Julie-Fabre/brain_street_view
Thank you to @kenneth-harris.bsky.social, @flickerfusion.bsky.social & @carandinilab.net lab.net for having been such amazing mentors and collaborators throughout my PhD!
Fabre, Carandini*, Peters*, Harris* www.biorxiv.org/content/10.6...
After task training, striatum still encodes stimulus identity, even when it is not behaviorally relevant. GPe and SNr encode behavioral salience: they mainly respond to Go stimuli, which means they only distinguish between Go and NoGo stimuli, and only in the Go/NoGo task.
To see how basal ganglia responses depend on behavioral relevance, we trained mice on two tasks, where the same stimuli had different contingencies. In the “All-Go” task, all require movement, in the “Go/No-Go” task, one stimulus does not.
We tested selectivity with a battery of visual stimuli. Striatum neurons were selective, encoding which precise stimulus was presented. GPe and SNr neurons were less selective: they signaled more that a stimulus was presented and less which stimulus was presented.
First, we looked at naive mice. Visual responses exist across all three nuclei, and they aren't random: they map onto a specific anatomical pathway through the basal ganglia, matching projections from visual cortex → dorsomedial striatum → GPe → SNr (Allen Connectivity Atlas).
How do the basal ganglia turn what you see into what you do?
New preprint w/ @kenneth-harris.bsky.social, @flickerfusion.bsky.social & @carandinilab.net: we recorded across striatum, GPe & SNr in a Go/NoGo task. Striatum encodes which stimulus, GPe & SNr encode action. 🧵
biorxiv.org/content/10.6...
Examples of sequences of activity seen in multiple regions of the brain
Sequences are everywhere! In every brain region. And are written in stone.
Invariant Activity Sequences Across the Mouse Brain.
Out today, by Célian Bimbard, with @kenneth-harris.bsky.social.
Based on data by Célian and by @intlbrainlab.bsky.social.
www.biorxiv.org/content/10.6...
Thanks, Adrian! I’m excited to be starting a lab at the University of Utah (theluolab.org)!
We’re recruiting at all levels.
If you’re excited about neural computation, large-scale multi-region recordings, and machine learning, let’s talk!
And yes, the mountains are as incredible as they say!
All talks of the 2025 UCL #Neuropixels course are now available: www.youtube.com/playlist?lis...
For more information on the course see the website: www.ucl.ac.uk/neuropixels/...
And for those at #SfN, come say hi at the #Neuropixels booth (Number 3731) or at my Poster 👋.
Happy Neuropixeling!
Our lab is looking for a postdoc! We have interesting projects and cutting-edge techniques such as Neuropixels Opto, Light Beads Microscopy and more. We would be delighted to receive your application. Deadline is 25 November 2025. More info here:
www.ucl.ac.uk/cortexlab/po...
Happy to share our primer on Basal Ganglia - Brainstem interactions!
From how the basal ganglia communicate with Brainstem motor circuits to how these activity patterns might come about! With Silvia Arber, now out in Current Biology www.cell.com/current-biol...
yay, this is great! Added it here: github.com/Julie-Fabre/...
Neuropixels Ultra!
By @steinmetzneuro.bsky.social, who led a big collaboration
www.sciencedirect.com/science/arti...
How does the brain decide? 🧠
Our new @nature.com paper shows that neural activity switches from an 'evidence gathering' to a 'commitment' state at a precise moment we call nTc.
After nTc, new evidence is ignored, revealing a neural marker for the instant when the mind is made up.
rdcu.be/eGUrv
PSA: don't buy duragel from Cambridge Neurotech, it's a scam! 🚨
They charge $200 (incl. shipping) for a 16 ml spout. But duragel is just DOWSIL 3-4680 (see paper below) of which you can buy a large container of 210 ml for only $110. That's 24 times cheaper! 💸
www.sciencedirect.com/science/arti...
We're looking for a research assistant to work in our neuroscience lab at @princetonneuro.bsky.social @hhmi.org where we study learning and decision-making circuitry.
Apply here: research-princeton.icims.com/jobs/21001/r...
Pls share w/ anyone who might be interested!
New by Agnès Landemard (@agnesland.bsky.social) & co
Brainwide blood volume reflects opposing neural populations
Brainwide fluctuations in blood volume arise from two populations with opposite relation to brain state and distinct relationships to blood supply
www.biorxiv.org/content/10.1...
Congrats!! 🎉
For now it is compatible with Kilosort only. However we want to extend this! The fastest way would be to create a github issue / email me so I can add support for another sorter. We're also keen to integrate / be compatible with the amazing spike interface - stay tuned for that :)
The firing of neural populations is high-dim even if their subthreshold activity is low-dim! This work by @bio-emergent.bsky.social and @haydari.bsky.social shows how, with a solvable model, a data analysis technique, and data from mouse visual cortex: www.biorxiv.org/content/10.1...
Big thanks to Sam Dodgson and @maxime-beau.bsky.social for help with this Python version
🧠 BONUS: bombcell can also calculate ephys properties and classify your striatal cells into MSN/FSI/TAN (and UIN) categories!
📈 How well does it work?
Preliminary data shows bombcell correctly labels white matter units, agrees with manual curation, and it is already in use in an estimated 30+ labs
Users can now also manually label a subset of units in the GUI, and bombcell will automatically suggest the optimal parameter thresholds for your dataset.
📊 Key feature
An important part of bombcell is the ability to quickly look at your data and quality metrics, using summary plots and an interactive GUI. Visual feedback makes it simple to fine-tune parameters for your specific needs.
