Brad Hulse

I am totally pumped about this new work . "Task-trained RNNs" are a powerful and influential framework in neuroscience, but have lacked a firm theoretical footing. This work provides one, and makes direct contact with the classical theory of random RNNs:
www.biorxiv.org/content/10.6...

fly circuit diagram

When a fly lands on your arm, how does your nervous system decide where to swat?

By reconstructing tactile axons in a Drosophila connectome, we found a leg somatotopic map and downstream circuits that sample the map to initiate targeted grooming

Led by Leila Elabbady, PhD

doi.org/10.64898/202...

Research Technician Research Technician position available in the Grienberger lab at Brandeis University. We are a new neuroscience group studying the cellular basis of learning and memory in the mammalian brain. This is...

We’re looking for a new Research Tech! Our research tech is heading to graduate school (very exciting!), which means we’re recruiting someone new to join our team. The position involves hands-on neuroscience research in a collaborative environment.
brandeis.wd5.myworkdayjobs.com/Jobs/job/Bra...

After 5 years of developing, a new preprint from the lab - introducing our workflow for comparative insect connectomics, aimed at democratizing connectomics. @erc.europa.eu @lundvision.bsky.social @biologylu.bsky.social Read it here: www.biorxiv.org/content/10.6...

If Grid Cells are the Answer, What is the Question? A Review of Normative Grid Cell Theory For 20 years the beautiful structure in the grid cell code has presented an attractive puzzle: what computation do these representations subserve, and why does it manifest so curiously in neurons. The...

2) Grid review.

A detailed tour of the ingredients needed to get grid cells that actually look real. It boils down to:
✅ Path integration
✅ Non-linear readout
✅ Bio constraints (non-negativity and energy)

Almost there on understanding grids!
arxiv.org/abs/2601.12424

(2/3)

Compact deep neural network models of the visual cortex Nature - Parsimonious deep neural network models can be used for prediction of visual neuron responses.

DNN models of the brain are getting bigger. Are we replacing one complicated system in vivo with another in silico?

In new work, we seek the *smallest* DNN models of visual cortex, balancing prediction with parsimony.

It turns out these compact models are surprisingly small!

rdcu.be/e5H8G

🚀 New preprint from the lab! Our first foray into the subiculum uses in vivo whole-cell recordings to show that dendritic plateaus are a prominent, learning-dependent signaling mode of subicular neurons. Feedback is welcome!

www.biorxiv.org/content/10.6...

Graph neural networks uncover structure and functions underlying the activity of simulated neural assemblies Graph neural networks trained to predict observable dynamics can be used to decompose the temporal activity of complex heterogeneous systems into simple, interpretable representations. Here we apply t...

This is work that we presented at last year's #Cosyne workshop on #GNN s sites.google.com/bu.edu/gnnwo.... Better late than never. You can reproduce everything with the associated notebooks. I think it's a good start to learn how to use GNNs to infer something about NNs. arxiv.org/abs/2602.13325

🔬🧠 Releasing the 1.0 version of #Suite2p and THE PAPER w/ @marius10p.bsky.social! Now with GPU acceleration. Want to use Suite2p but don’t have 100,000 neuron recordings? We show you how to get those with a standard 2p microscope #neuroscience #imaging #neuroAI www.biorxiv.org/content/10.6...

New paper alert! 🚨

We found that the brain's compass is remarkably stable at two scales

1️⃣ the system maintains its internal organization for weeks
2️⃣ It "remembers" its orientation for weeks, even after a single visit

This may be key to how the brain aligns its other maps.

Paper: rdcu.be/e3waP

We had a lot of fun doing these experiments! Theta sweeps in MEC and internal direction signals in parasubiculum track moving objects during pursuit and reverse during backward movement. Simultaneously recorded HD cells in other areas remain locked to head direction across behaviors:

The hippocampal map has its own attentional control signal!
Our new study reveals that theta #sweeps can be instantly biased towards behaviourally relevant locations. See 📹 in post 4/6 and preprint here 👉
www.biorxiv.org/content/10.6...
🧵(1/6)

Plastic landmark anchoring in zebrafish compass neurons Nature - Using two-photon microscopy with a panoramic virtual reality setup, how head direction cells in larval zebrafish integrate visual landmarks and optic flow to track orientation is revealed.

1/6: New publication from the lab: “Plastic landmark anchoring in zebrafish compass neurons” by Ryosuke Tanaka (@ryosuketanaka.bsky.social) and Ruben is available here:
rdcu.be/eX1L4

New preprint from the lab! 🚀
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!

Neuronal calcium spikes enable vector inversion in the Drosophila brain In the fly central complex, PFNa neurons switch from firing classical sodium spikes when depolarized to firing non-canonical T-type calcium spikes when hyperpolarized. This bidirectional spiking allow...

www.cell.com/cell/fulltex...

We had a lot of fun working on this project (led by Itzel Ishida, not on bluesky). Some interesting highlights from the paper -

Projection-specific integration of convergent thalamic and retrosplenial signals in the presubicular head direction cortex Nonlinear dendritic integration in single presubicular neurons provides a mechanism for combining vestibular-based head-direction signals and visual landmark signals to anchor the brain’s internal com...

Coincidence of thalamic HD signal and retrosplenial visual input is detected in the Presubiculum! 🎯 This may be the neuronal basis for landmark anchoring of the HD signal. Pleased to announce the VOR is now available elifesciences.org/articles/92443 Congrats first author Louis Richevaux 🙌

1/n: A new collaborative preprint from the lab to start the year: "A multi-ring shifter network computes head direction in zebrafish" together with Siyuan Mei, Martin Stemmler and Andreas Herz from the LMU, Munich.

On the left, the image shows a schematic of a fly head, ring neurons and EPG neurons together with some calcium imaging frames. On the right is a photo of a fly on a ball in virtual reality and another schematic of a VR system.

📢 Join us, the Haberkern lab, @uni-wuerzburg.de for a postdoc studying neural circuit mechanisms of navigation. You’ll spearheading neurophysiology experiments on our brand new 2P!

⏳ Apply by 28th February 2026

Details: www.haberkernlab.de/docs/ENPostd...

#neuroscience #academicjobs #postdoc

Landing and takeoff sensorimotor pathways illustrated alongside fly drawings showing behavioral responses.

How do animals channel sensory information into motor pathways to generate flexible behavioral output? Excited to share a new preprint addressing this question by leveraging the new #maleCNS connectome, behavioral experiments, and in-vivo recordings: doi.org/10.64898/202.... A long🧵...

I am incredibly excited and proud to share my first preprint from my postdoc! Thank you to all of the co-authors for all your hard work!
Check out the paper for big insights into plasticity mechanisms in navigation circuits! And surprising motifs for inhibitory synaptic plasticity!

Schematic of how ER-EPG plasticity enables the bump of activity in EPGs to accurately track visual cues. As a fly makes a counter-clockwise turn (top to bottom) it will view visual cues (e.g. the sun) from a new angle and the EPG activity bump (red) will swing clockwise around the network by integrating self motion signals with these visual inputs. When the fly faces a different angle, distinct visual ER neurons are active. Plasticity forms a trough of weak synapses (large circles - strong synapses, small circles - weak synapses) that allow ER neurons with distinct visual tuning to move the EPG bump via disinhibition.

*First preprint from our lab* !!!!!
How does the brain learn to anchor its internal sense of direction to the outside world? 🧭
led by Mark Plitt @markplitt.bsky.social & Dan Turner-Evans, w/ Vivek Jayaraman:
“Octopamine instructs head direction plasticity” www.biorxiv.org/content/10.6...
Thread ⬇️

An awesome figure illustrating key aspects of hippocampal encoding and replay during continuous behavior ; from great work by Brian Lustig and co www.biorxiv.org/content/10.6...

How do neural circuits generate the walking rhythm?

Using connectome simulations, @sarahpugly.bsky.social found a minimal central pattern generator (CPG) that produces oscillations in leg motor neurons. Same circuit motif for each 🪰 leg.

w @bingbrunton.bsky.social

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

Have you ever wondered what you would find if you could keep your eyes on a bee for more than a few meters? Us, too!

preprint (with videos!) + thread 🧵

Precise, individualized foraging flights in honey #bees 🐝 revealed by multicopter drone-based tracking

www.biorxiv.org/content/10.6...

1/9

Composing trajectories for rapid inference of navigational goals Animals efficiently learn to navigate their environment. In the laboratory, naive mice explore their environment via highly structured trajectories and can learn to localize new spatial targets in as ...

I am very much in favor, we just put out a recent preprint thinking about learning to navigate from the perspective of generative models of trajectories www.biorxiv.org/content/10.1...

0/10 Thanks for the interest in our preprint. Some takes say it negates or fully supports the “manifold hypothesis”, neither quite right. Our results show that if you only focus on the manifold capturing most of task-related variance, you could miss important dynamics that actually drive behavior.

Visual motion and landmark position align with heading direction in the zebrafish interpeduncular nucleus - Nature Communications How are various visual signals integrated in the vertebrate brain for navigation? Here authors show that different spatial signals are topographically organized and align to one another in the zebrafi...

(1/n) We are excited to share our new paper in Nature Communications, by Hagar Lavian (@hlavian.bsky.social) and team, revealing how the zebrafish brain integrates visual navigation signals! www.nature.com/articles/s41...

YouTube video by Weizmann Institute of Science Bat Island: The New Era of Science

Neuroscience projects last several years, and you are usually a bit jaded by the time you wrap it up. Not this one– spending several months on an island in the middle of nowhere, away from all the craziness of the world reminds you how beautiful the world really is.

www.youtube.com/watch?v=46sv...

The postsubiculum as a head-direction cortex The organisation of thalamocortical networks follows a conserved structure. Traditionally, these are divided into primary sensory systems that receive…

Really excited to share this Opinion piece we've been working on with fellow head-direction cell geeks @apeyrache.bsky.social @desdemonafricker.bsky.social and (bsky-less?) Andrea Burgalossi! While head-direction cells pop up in many cortical regions, we think that one of them is quite unique (1/8)

🌟 Apply to lead a lab at Janelia 🌟

We’re #hiring Group Leaders in our Computation & Theory research area.

🔹 5-year renewable appointment
🔹 Internal funding + generous resources
🔹 Collaboration across disciplines

📅 Apply by Nov. 4 👉 https://janelia.link/groupleader