Aditya Krishna speaks about "Predictive coding of moving objects in the #bat #hippocampus" 🦇🧠 #ICN2026
Aditya Krishna
@adikrish.bsky.social
PhD student at Johns Hopkins Bat Lab | Hopkins Kavli NDI Distinguished Graduate Fellow| bats, hippocampus
Our new paper is out in @nature.com! We uncovered how a naked mole-rat queen 👑 controls an entire colony: a natural contraceptive scent that suppresses reproduction in other females! A remarkable mammalian parallel to bees and ants! 🐝🐜 @garyrlewin.bsky.social youtu.be/enfv3zJrWKM?...
Naked mole-rats are ruled by a queen: this chemical puts her in power
YouTube video by nature video
youtu.be
Our work on goal-directed theta sweeps is out! We found two different types of theta sweeps in the rat hippocampus. During random foraging, left-right alternating sweeps dominated (Vollan, 25). However, during memory-guided navigation sweeps pointing to hidden goal locations emerged with learning.
Fresh off the press! Jeongeun and Yoël’s work on the lightning-fast actuation of the Venus flytrap. 🪴⚡ No muscles. No nerves. So what powers the trap? Cutting the trap suppresses its mechanical amplifier, the snap-through instability, and reveals the active motion. www.science.org/doi/10.1126/...
A Two-Dimensional Grid-Cell Code for Three-Dimensional Navigation in Freely Flying Bats https://www.biorxiv.org/content/10.64898/2026.06.10.728358v1
Excited to share a review with @gracecapshaw.bsky.social and @batwoman123.bsky.social in Current Opinion in Neurobiology! Natural auditory behaviors invoke cognitive brain networks. www.sciencedirect.com/science/arti...
Natural auditory behaviors invoke cognitive brain networks
Auditory processing is traditionally framed as a hierarchical extraction of acoustic features along a canonical ascending pathway, starting in the coc…
sciencedirect.com
New paper from Ulanovsky's group: With brain recordings from🦇 flying in a 200m tunnel, the group discovered that place cells of CA1 exhibit dense spatial coding, i.e., multiple place fields, and cells of CA3 exhibit ultrasparse coding, i.e., one place field. www.nature.com/articles/s41...
Sparse-to-dense coding transformation between hippocampal areas CA3 and CA1 - Nature
The hippocampus exhibits a CA3-to-CA1 coding transformation that combines fast learning with an efficient, compressed neural code.
nature.com
How does #vision shape spatial maps in the hippocampus? Check out our brand new preprint 👇 As someone who did a PhD on the #hippocampus & postdoc on visual cortex and superior colliculus, it's such a joy to start closing the loop - especially with such a great team! 😊
bioRxiv Neuroscience@biorxiv-neursci.bsky.social · 3mo agoVision shapes neural maps of space through an ancient midbrain pathway https://www.biorxiv.org/content/10.64898/2026.05.16.725555v1
Where, exactly, does learning happen in the brain? Out today in @nature.com, we identify a synaptic locus of birdsong learning and show that the circuit can be tuned to make birds learn faster - but at a cost. Read on👇 #neuroskyence 🧪 #prattle 💬 #bioacoustics Shareable link: rdcu.be/fiyrS
A synaptic locus of song learning - Nature
Combining a computational framework and optogenetic and chemogenetic manipulations within and downstream of the cortico-basal ganglia circuit identifies the specific cortico-basal ganglia synapse...
nature.com
Rethinking hierarchy: the auditory system as an integrated cortical–subcortical network www.nature.com/articles/s41...
Rethinking hierarchy: the auditory system as an integrated cortical–subcortical network - Nature Reviews Neuroscience
The auditory system differs from other senses in the complexity of its subcortical pathways. King and colleagues examine how subcortical structures transform sound representations and integrate sensor...
nature.com
Really excited to see this in print!
Cedric Boeckx@cedricboeckx.bsky.social · 3mo ago“Specific expansion of motor cortical projections in a singing mouse” Great new work by @arkarupbanerjee.bsky.social E. Isco @cliffscience.bsky.social @xmikezheng20.bsky.social @tonyzador.bsky.social & colleagues on the neural basis of vocal dexterity, now out in @nature.com 🧪🧠
Preprint alert! We've done the first ever wireless brain recordings from the high-level visual & motor regions (IT/PMv/PFC) in monkeys engaged in natural behaviors as well as during controlled screen-based tasks. Read below for a lay summary and the link for details! 1/8
Very excited to announce the first preprint from the lab @ucsantabarbara.bsky.social -- "Predictive pursuit emerges in high-dimensional RNNs." @wtredman.bsky.social (starting his own group at JHU this fall) summarizes the work nicely in this thread.
Will Redman@wtredman.bsky.social · 3mo agoNew preprint out 🚨 “Predictive pursuit emerges in high-dimensional recurrent neural networks”! This was an awesome collaboration with co-first author @fatihdinc.bsky.social , @andyalexander.bsky.social, @xiaoxiao-lin.bsky.social, and May Chen biorxiv.org/content/10.6... 1/
1/7 🧠 My journey into development begins with this work and question: how does the brain's spatial navigation system develop? We found that the neural networks for spatial navigation (tori and rings) are preconfigured and only later anchor gradually to the world with experience! 🧵
Edvard I Moser@edvardmoser.bsky.social · 5mo agoIs spatial navigation innate 🧠? Using #NeuroPixels we show that the #torus 🍩 underlying the #GridCell map exists already on day 10 in rats — before pups open eyes and ears and before they start upright walking. 🧵1:4 👇 www.biorxiv.org/content/10.6...
the human hippocampus receives convergent input from multiple sensory systems, yet we lack a basic understanding of how this structure integrates across senses. we tackle this problem in our new preprint! paper: doi.org/10.64898/202... w/ Aryan Agarwal, @yannanzhu.bsky.social, & Nick Turk-Browne
How can moths navigate for THOUSANDS of kilometres in the dark? Read more in this research article and related Insight article about moths called fall armyworms in @elife.bsky.social: elifesciences.org/reviewed-pre... elifesciences.org/articles/110... Image credit: David Hobern CC BY 2.0
New preprint out 🎉 What happens to the hippocampal “place code” when an animal is actively engaged in a task? The answer surprised us (and might surprise you too!). Let's dive in ⬇️ Link: "Hippocampal trace coding dominates and disrupts place coding" www.biorxiv.org/content/10.6...
biorxiv.org
A half-century old question may have its final answer. Using high-resolution #Mini2P microscopes, we find no evidence of local topography in #PlaceCells. Place fields of neighbouring cells are no more similar than those of randomly selected cells. 🧠🗺️ Out now in @pnas.org www.pnas.org/doi/10.1073/...
Place cells in CA1 lack topographical organization of firing locations | PNAS
Topography is a well-described and well-known concept for cortical organization in primary sensory and motor cortices of mammalian brains. Similar ...
pnas.org
Thrilled to finally share this work! 🧠🔊 Using a new reinforcement-free task we show mice (like humans) extract abstract structure from sound (unsupervised) & dCA1 is causally required by building factorised, orthogonal subspaces of abstract rules. Led by Dammy Onih! www.biorxiv.org/content/10.6...
biorxiv.org
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
I made a map of 3.4 million Bluesky users - see if you can find yourself! bluesky-map.theo.io I've seen some similar projects, but IMO this seems to better capture some of the fine-grained detail
Bluesky Map
Interactive map of 3.4 million Bluesky users, visualised by their follower pattern.
bluesky-map.theo.io
Imagination in bonobos! I am thrilled to share a new paper w/ Amalia Bastos, out now in @science.org We provide the first experimental evidence that a nonhuman animal can follow along a pretend scenario & track imaginary objects. Work w/ Kanzi, the bonobo, at Ape Initiative youtu.be/NUSHcQQz2Ko
Apes Share Human Ability to Imagine
YouTube video by Johns Hopkins University
youtu.be
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)
Attention-like regulation of theta sweeps in the brain's spatial navigation circuit
Spatial attention supports navigation by prioritizing information from selected locations. A candidate neural mechanism is provided by theta-paced sweeps in grid- and place-cell population activity, which sample nearby space in a left-right-alternating pattern coordinated by parasubicular direction signals. During exploration, this alternation promotes uniform spatial coverage, but whether sweeps can be flexibly tuned to locations of particular interest remains unclear. Using large-scale Neuropixels recordings in freely-behaving rats, we show that sweeps and direction signals are rapidly and dynamically modulated: they track moving targets during pursuit, precede orienting responses during immobility, and reverse during backward locomotion — without prior spatial learning. Similar modulation occurs during REM sleep. Canonical head-direction signals remain head-aligned. These findings identify sweeps as a flexible, attention-like mechanism for selectively sampling allocentric cognitive maps. ### Competing Interest Statement The authors have declared no competing interest. European Research Council, Synergy Grant 951319 (EIM) The Research Council of Norway, Centre of Neural Computation 223262 (EIM, MBM), Centre for Algorithms in the Cortex 332640 (EIM, MBM), National Infrastructure grant (NORBRAIN, 295721 and 350201) The Kavli Foundation, https://ror.org/00kztt736 Ministry of Science and Education, Norway (EIM, MBM) Faculty of Medicine and Health Sciences; NTNU, Norway (AZV)
biorxiv.org
Where does learning through imitation happen in the brain? In juvenile zebra finches, we pinpoint a synaptic locus of song learning in a cortico-basal ganglia circuit and leverage this localization to measure the timescale of consolidation and make birds learn faster! #neuroskyence (1/14)
A synaptic locus of song learning
Learning by imitation is the foundation for verbal and musical expression, but its underlying neural basis remains obscure. A juvenile male zebra finch imitates the multisyllabic song of an adult tutor in a process that depends on a song-specialized cortico-basal ganglia circuit, affording a powerful system to identify the synaptic substrates of imitative motor learning. Plasticity at a particular set of cortico-basal ganglia synapses is hypothesized to drive rapid learning-related changes in song before these changes are subsequently consolidated in downstream circuits. Nevertheless, this hypothesis is untested and the synaptic locus where learning initially occurs is unknown. By combining a computational framework to quantify song learning with synapse-specific optogenetic and chemogenetic manipulations within and directly downstream of the cortico-basal ganglia circuit, we identified the specific cortico-basal ganglia synapses that drive the acquisition and expression of rapid vocal changes during juvenile song learning and characterized the hours-long timescale over which these changes consolidate. Furthermore, transiently augmenting postsynaptic activity in the basal ganglia briefly accelerates learning rates and persistently alters song, demonstrating a direct link between basal ganglia activity and rapid learning. These results localize the specific cortico-basal ganglia synapses that enable a juvenile songbird to learn to sing and reveal the circuit logic and behavioral timescales of this imitative learning paradigm. ### Competing Interest Statement The authors have declared no competing interest. National Institutes of Health, K99 NS144525 (DCS), F32 MH132152 (DCS), F31 HD098772 (SB), R01 NS099288 (RM), RF1 NS118424 (RM and JP)
biorxiv.org
Cow Tools! We have lived alongside cows for nearly 10,000 years. We breed them and exploit them It is now, only now, that we have discovered THEY CAN USE TOOLS Here I describe our study (paper) www.sciencedirect.com/science/arti... in @currentbiology.bsky.social with @auersperga.bsky.social
Another new paper from the lab: Predictive theories like the SR imply that navigators who navigate differently should have cognitive maps which differ in predictable ways. Here we show that this holds in mouse hippocampal CA1. www.sciencedirect.com/science/arti...
Environmental representations in mouse hippocampal CA1 reflect the predictive structure of navigation
Predictive theories of cognitive mapping propose that these representations encode the predictive relationships among contents as experienced by the n…
sciencedirect.com
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.
Dan Levenstein@dlevenstein.bsky.social · 9mo ago“Our findings challenge the conventional focus on low-dimensional coding subspaces as a sufficient framework for understanding neural computations, demonstrating that dimensions previously considered task-irrelevant and accounting for little variance can have a critical role in driving behavior.”
(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...
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...
nature.com
As a longtime fan of cool papers in @currentbiology.bsky.social, I am really thrilled to see this out! This study sets the stage for understanding the origins of novel (vocal) behaviors. Big shout out to the main architects of this work @xmikezheng20.bsky.social and @cliffscience.bsky.social
Cedric Boeckx@cedricboeckx.bsky.social · 9mo agoGreat @currentbiology.bsky.social study by @xmikezheng20.bsky.social @cliffscience.bsky.social @arkarupbanerjee.bsky.social 🧪🧠🐭🎶 Vocal repertoire expansion in singing mice by co-opting a conserved midbrain circuit node www.cell.com/current-biol...