Arnav Raha
@pantamallion.bsky.social
Neuroscience PhD student at Columbia University | UC Berkeley alum | Studying RL mechanisms for vocal learning (+ fan of animals 🐋🦇🦜🦋🦑 🦎🦕)
Pinned
Arnav Raha
@pantamallion.bsky.social
· Mar 17
Excited to share our latest work! It’s been a great experience working on this (including building a whole new lab!) 😊
www.nature.com/articles/s41...
www.nature.com/articles/s41...
Natural behaviour is learned through dopamine-mediated reinforcement - Nature
Studies in zebra finches show that dopamine has a key role as a reinforcement signal in the trial-and-error process of learning that underlies complex natural behaviours.
www.nature.com
We know dopamine guides reinforcement learning in externally rewarded behaviors—think a mouse learning to press a lever for food or juice. But what about skills like speech or athletics, where there’s no explicit external reward, just an internal goal to match? 🧵 (1/7)
Reposted by Arnav Raha
Now in PRX: Theory linking connectivity structure to collective activity in nonlinear RNNs!
For neuro fans: conn. structure can be invisible in single neurons but shape pop. activity
For low-rank RNN fans: a theory of rank=O(N)
For physics fans: fluctuations around DMFT saddle⇒dimension of activity
For neuro fans: conn. structure can be invisible in single neurons but shape pop. activity
For low-rank RNN fans: a theory of rank=O(N)
For physics fans: fluctuations around DMFT saddle⇒dimension of activity
Connectivity Structure and Dynamics of Nonlinear Recurrent Neural Networks
The structure of brain connectivity predicts collective neural activity, with a small number of connectivity features determining activity dimensionality, linking circuit architecture to network-level...
journals.aps.org
November 3, 2025 at 9:47 PM
Now in PRX: Theory linking connectivity structure to collective activity in nonlinear RNNs!
For neuro fans: conn. structure can be invisible in single neurons but shape pop. activity
For low-rank RNN fans: a theory of rank=O(N)
For physics fans: fluctuations around DMFT saddle⇒dimension of activity
For neuro fans: conn. structure can be invisible in single neurons but shape pop. activity
For low-rank RNN fans: a theory of rank=O(N)
For physics fans: fluctuations around DMFT saddle⇒dimension of activity
Reposted by Arnav Raha
2025. Norway Rats Exhibit Social Learning in Nature bioengineer.org/norway-rats-...
Norway Rats Exhibit Social Learning in Nature
In an exciting breakthrough, researchers have provided substantial evidence for social learning in semi-natural settings using wild-type Norway rats. This groundbreaking study has cast new light on
bioengineer.org
November 3, 2025 at 4:47 AM
2025. Norway Rats Exhibit Social Learning in Nature bioengineer.org/norway-rats-...
Reposted by Arnav Raha
not to be confused with quesadilla
October 27, 2025 at 7:21 PM
not to be confused with quesadilla
Reposted by Arnav Raha
Learn more about his research: zuckermaninstitute.columbia.edu/vikram-gadag... and meet his mentees, Jonathan Kasdin zuckermaninstitute.columbia.edu/pianist-lear... & Arnav Raha: zuckermaninstitute.columbia.edu/science-life...
October 23, 2025 at 5:35 PM
Learn more about his research: zuckermaninstitute.columbia.edu/vikram-gadag... and meet his mentees, Jonathan Kasdin zuckermaninstitute.columbia.edu/pianist-lear... & Arnav Raha: zuckermaninstitute.columbia.edu/science-life...
Come learn about naked mole rat brains!
NYC 🗣️
Please join/spread the word of this free neuroscience event!
Our LNS team puts on monthly events that are open to the public that are intended to give our NYC community insight on what happens in a Columbia lab. A tour of the lab space is provided! Please share! 🧠🌙
Please join/spread the word of this free neuroscience event!
Our LNS team puts on monthly events that are open to the public that are intended to give our NYC community insight on what happens in a Columbia lab. A tour of the lab space is provided! Please share! 🧠🌙
October 23, 2025 at 12:17 AM
Come learn about naked mole rat brains!
Reposted by Arnav Raha
I get that the news cycle is packed right now, but I just heard from a colleague at the Smithsonian that this is fully a GIANT SQUID BEING EATEN BY A SPERM WHALE and it’s possibly the first ever confirmed video according to a friend at NOAA
10 YEAR OLD ME IS LOSING HER MIND (a thread 🧵)
10 YEAR OLD ME IS LOSING HER MIND (a thread 🧵)
September 24, 2025 at 8:30 PM
I get that the news cycle is packed right now, but I just heard from a colleague at the Smithsonian that this is fully a GIANT SQUID BEING EATEN BY A SPERM WHALE and it’s possibly the first ever confirmed video according to a friend at NOAA
10 YEAR OLD ME IS LOSING HER MIND (a thread 🧵)
10 YEAR OLD ME IS LOSING HER MIND (a thread 🧵)
Reposted by Arnav Raha
New video about a piece by the modern artist Sol LeWitt, and the group theory behind it.
youtu.be/_BrFKp-U8GI
youtu.be/_BrFKp-U8GI
September 7, 2025 at 12:39 PM
New video about a piece by the modern artist Sol LeWitt, and the group theory behind it.
youtu.be/_BrFKp-U8GI
youtu.be/_BrFKp-U8GI
Reposted by Arnav Raha
Reminded again of Kevin Murphy's excellent RL overview: arxiv.org/abs/2412.05265
A lot of the stuff covered here really is at the cutting edge and not compiled so nicely anywhere else
A lot of the stuff covered here really is at the cutting edge and not compiled so nicely anywhere else
Reinforcement Learning: An Overview
This manuscript gives a big-picture, up-to-date overview of the field of (deep) reinforcement learning and sequential decision making, covering value-based methods, policy-based methods, model-based m...
arxiv.org
September 3, 2025 at 1:47 AM
Reminded again of Kevin Murphy's excellent RL overview: arxiv.org/abs/2412.05265
A lot of the stuff covered here really is at the cutting edge and not compiled so nicely anywhere else
A lot of the stuff covered here really is at the cutting edge and not compiled so nicely anywhere else
woah are the japanese 鳥類 (chorui?) & bangla চড়ুই (chorui) somehow related or is it (I presume) just a fun coincidence
August 29, 2025 at 11:58 PM
woah are the japanese 鳥類 (chorui?) & bangla চড়ুই (chorui) somehow related or is it (I presume) just a fun coincidence
Reposted by Arnav Raha
(1/26) Excited to share a new preprint led by grad student Albert Wakhloo, with me and Larry Abbott: "Associative synaptic plasticity creates dynamic persistent activity."
www.biorxiv.org/content/10.1...
www.biorxiv.org/content/10.1...
Associative synaptic plasticity creates dynamic persistent activity
In biological neural circuits, the dynamics of neurons and synapses are tightly coupled. We study the consequences of this coupling and show that it enables a novel form of working memory. In recurren...
www.biorxiv.org
August 25, 2025 at 5:17 PM
(1/26) Excited to share a new preprint led by grad student Albert Wakhloo, with me and Larry Abbott: "Associative synaptic plasticity creates dynamic persistent activity."
www.biorxiv.org/content/10.1...
www.biorxiv.org/content/10.1...
It was a great experience mentoring this cohort for the past 8 months—excited to see what they get up to next!
Last week we proudly celebrated the graduating BRAINYAC class with a poster session highlighting the students’ research! BRAINYAC partners 10th & 11th graders from schools in Upper Manhattan & the Bronx with @columbiauniversity.bsky.social neuroscientists.
August 23, 2025 at 9:30 PM
It was a great experience mentoring this cohort for the past 8 months—excited to see what they get up to next!
Reposted by Arnav Raha
New preprint!
tl;dr — We ran around late at night to record wild rats in NYC and figured out how to quantify their behavior and environment. 🧵
w/ Dima Batenkov, @zamakany.bsky.social, Emily Mackevicius
www.biorxiv.org/content/10.1...
tl;dr — We ran around late at night to record wild rats in NYC and figured out how to quantify their behavior and environment. 🧵
w/ Dima Batenkov, @zamakany.bsky.social, Emily Mackevicius
www.biorxiv.org/content/10.1...
Computational Urban Ecology of New York City Rats
Urban rats are highly adaptable, thriving in the dynamic and often inhospitable conditions of modern cities. Despite substantial mitigation efforts, they remain an enduring presence in urban environme...
www.biorxiv.org
July 25, 2025 at 3:57 PM
New preprint!
tl;dr — We ran around late at night to record wild rats in NYC and figured out how to quantify their behavior and environment. 🧵
w/ Dima Batenkov, @zamakany.bsky.social, Emily Mackevicius
www.biorxiv.org/content/10.1...
tl;dr — We ran around late at night to record wild rats in NYC and figured out how to quantify their behavior and environment. 🧵
w/ Dima Batenkov, @zamakany.bsky.social, Emily Mackevicius
www.biorxiv.org/content/10.1...
Reposted by Arnav Raha
Proud to make my National Geographic debut with this incredible discovery! Meet Mirasaura, an extremely weird little guy with independently-evolved "feathers" that solves a longstanding Triassic mystery and makes one of the period's oddest families even stranger.
(Now with a fixed link!)
(Now with a fixed link!)
Is it a bird? A monkey? No, it's a 'miraculous' new prehistoric reptile
Mirasaura grauvogeli had a featherlike crest and a tail like a monkey. “It's been a long time since I've been so blown away by a new fossil discovery.”
www.nationalgeographic.com
July 23, 2025 at 6:30 PM
Proud to make my National Geographic debut with this incredible discovery! Meet Mirasaura, an extremely weird little guy with independently-evolved "feathers" that solves a longstanding Triassic mystery and makes one of the period's oddest families even stranger.
(Now with a fixed link!)
(Now with a fixed link!)
Reposted by Arnav Raha
I am happy to share that I’ve been awarded tenure here at Columbia University. Alhamdulillah. I thank my wife, parents, mentors, colleagues, friends, and family. I thank my lab members, present and past, for entrusting their careers in my hands and making this a thrilling journey.
July 2, 2025 at 1:43 PM
I am happy to share that I’ve been awarded tenure here at Columbia University. Alhamdulillah. I thank my wife, parents, mentors, colleagues, friends, and family. I thank my lab members, present and past, for entrusting their careers in my hands and making this a thrilling journey.
Reposted by Arnav Raha
We are looking for early carrer researchers who want to share their fascination for Neuroethology by introducing their work.
July 2, 2025 at 2:29 PM
We are looking for early carrer researchers who want to share their fascination for Neuroethology by introducing their work.
Reposted by Arnav Raha
Mamdani winning and it's not even close! Rejection of Machiavellian power-mad sex-harasser w full support of Dem establishment & $20M in PAC $$, in favor of a young fresh, guy really committed to ordinary people with a huge grassroots volunteer effort. Huge grassroots victory!
June 25, 2025 at 2:09 AM
Mamdani winning and it's not even close! Rejection of Machiavellian power-mad sex-harasser w full support of Dem establishment & $20M in PAC $$, in favor of a young fresh, guy really committed to ordinary people with a huge grassroots volunteer effort. Huge grassroots victory!
Reposted by Arnav Raha
"GOOD FUCKING RIDDANCE"
June 25, 2025 at 2:26 AM
"GOOD FUCKING RIDDANCE"
Reposted by Arnav Raha
When we run leftist candidates, those candidates win. Because leftist values ARE the values the people believe in. Respond to. Show up for.
Whatever the donor class may tell you, and however hard they may fight us, remember that. These are the policies that WIN.
Whatever the donor class may tell you, and however hard they may fight us, remember that. These are the policies that WIN.
June 25, 2025 at 2:13 AM
When we run leftist candidates, those candidates win. Because leftist values ARE the values the people believe in. Respond to. Show up for.
Whatever the donor class may tell you, and however hard they may fight us, remember that. These are the policies that WIN.
Whatever the donor class may tell you, and however hard they may fight us, remember that. These are the policies that WIN.
Reposted by Arnav Raha
My latest Aronov lab paper is now published @Nature!
When a chickadee looks at a distant location, the same place cells activate as if it were actually there 👁️
The hippocampus encodes where the bird is looking, AND what it expects to see next -- enabling spatial reasoning from afar
bit.ly/3HvWSum
When a chickadee looks at a distant location, the same place cells activate as if it were actually there 👁️
The hippocampus encodes where the bird is looking, AND what it expects to see next -- enabling spatial reasoning from afar
bit.ly/3HvWSum
June 11, 2025 at 10:24 PM
My latest Aronov lab paper is now published @Nature!
When a chickadee looks at a distant location, the same place cells activate as if it were actually there 👁️
The hippocampus encodes where the bird is looking, AND what it expects to see next -- enabling spatial reasoning from afar
bit.ly/3HvWSum
When a chickadee looks at a distant location, the same place cells activate as if it were actually there 👁️
The hippocampus encodes where the bird is looking, AND what it expects to see next -- enabling spatial reasoning from afar
bit.ly/3HvWSum
Reposted by Arnav Raha
Check out my review of Is Anyone Listening?: What Animals Are Saying to Each Other and to Us by marine biologist and dolphin researcher Denise L. Herzing, published in Current Biology:
www.cell.com/curre.../abs...
www.cell.com/curre.../abs...
May 19, 2025 at 6:16 PM
Check out my review of Is Anyone Listening?: What Animals Are Saying to Each Other and to Us by marine biologist and dolphin researcher Denise L. Herzing, published in Current Biology:
www.cell.com/curre.../abs...
www.cell.com/curre.../abs...
Reposted by Arnav Raha
youtube.com/shorts/v-JNF...
Incredible, not just a "how did dinosaurs go from teeth to beaks" but also how young and old animals had completely different diets.
Incredible, not just a "how did dinosaurs go from teeth to beaks" but also how young and old animals had completely different diets.
Chew on This! Or...Maybe Not...
YouTube video by Your Dinosaurs Are Wrong
youtube.com
June 13, 2025 at 1:56 AM
youtube.com/shorts/v-JNF...
Incredible, not just a "how did dinosaurs go from teeth to beaks" but also how young and old animals had completely different diets.
Incredible, not just a "how did dinosaurs go from teeth to beaks" but also how young and old animals had completely different diets.
Reposted by Arnav Raha
Found a baby songbird? Here's a newly updated chart!
May 22, 2025 at 3:01 PM
Found a baby songbird? Here's a newly updated chart!
