Thrilled to share that I’ll be starting my lab at the SickKids Research Institute and University of Toronto in August! williamsonlab.ca Recruiting at all levels. Get in touch if you’re interested in astrocyte biology of cognition and disease!

A great kickstart to #CAN 2026 in Montreal

New paper from the lab. Using longitudinal ca imaging, activity-dependent tagging and optogenetics, we show that newly allocated fear engram neurons in amygdala undergo a brief period of coordinated “offline reverberation” immediately after learning. www.pnas.org/doi/10.1073/...

Some more Brain-Machine Interface shenanigans: this time we think we found evidence that an animal's agency in a task modulates hippocampal maps of that task. www.biorxiv.org/content/10.6...

Thanks to @utoronto.ca for featuring my research on social memory and translating memory mechanisms in the brain into better AI. Read the full story: www.instagram.com/p/DYCtendkST...

What if memories could be rewritten? #UofT researcher Sheena Josselyn studies how memories are encoded, stored & recalled, and how they might be reprogrammed or erased, advancing research on PTSD and Alzheimer’s disease. 🧠 uoft.me/josselyn-s

Meet Sofiya Zbaranska, a neuroscience PhD student in our lab developing brain-inspired machine learning algorithms. #neuroscience #AI @compneurolab.bsky.social

Stunning British Columbia, long overdue

Happy Ukrainian Easter 💛

You've seen place cells, grid cells, mirror neurons, now... huddle cells! Neurons in the rodent frontal cortex (dorsomedial region) appear to track huddling from the cold and much more detail in this impressive Nature study: www.nature.com/articles/s41...

Nonchalant in Tremblant

Join us December 5th at University of Toronto (in-person and online) for a special seminar by Dr. Aran Nayebi on reverse-engineering the brain and building neuroscience-inspired artificial intelligence. #neuroAI #compneuro @anayebi.bsky.social @utoronto.ca @uoftcompsci.bsky.social

New paper from the lab 🚨 Led by Ali Golbabaei, this study explores the how the composition of prefrontal cortical engrams changes with memory age: authors.elsevier.com/a/1lzT-3BtfH...

Had a pleasure to give an invited talk at UCU on engrams and how they support various memory phenomena: youtu.be/ETVgqyQwZVM?...

Imagine a brain decoding algorithm that could generalize across different subjects and tasks. Today, we’re one step closer to achieving that vision. Introducing the flagship paper of our brain decoding program: www.biorxiv.org/content/10.1... #neuroAI #compneuro @utoronto.ca @uhn.ca

Looking forward to giving a talk on the latest developments in engram research 🧠
The main lecture will be in English, with a part on my own research in Ukrainian. Kindly hosted by Ukrainian Catholic University — everyone’s welcome! Register via the QR code 👇

“If everything is everywhere, why have distinct areas? Here we show that the function of a brain area is more related to how different types of information are combined (formatted) in neural representations than merely whether that information is present.”

Despite its efficiency, the brain is oddly inefficient: requires ~8 hours of sleep for every 16 hours of runtime. We spend a third of our lives recharging.

Come join us at University of Toronto. We're hiring a Professor of computational cognitive neuroscience. #neuroAI #compneuro jobs.utoronto.ca/job/Toronto-...

#IBB shared some highlights from their visit to @sjo09.bsky.social lab. It was rewarding to see how much interest was sparked by #engrams as well as #ML and #NeuroAI 🧠✨ Shoutout to @mhsarikahya.bsky.social & other JF lab members!

Wrapped up 2 intense weeks at #NeuroAI by @neuromatch.bsky.social! 🚀 Our team explored how RNNs encode spatial memory — and found they implicitly learn a discrete spatial layout. 🔍 Check it out: github.com/neur1s/GridVaders Thanks to my amazing teammates! #AI #Neuroscience #RNN #GridWorld

(1/7) New preprint from Rajan lab! 🧠🤖 @ryanpaulbadman1.bsky.social & Riley Simmons-Edler show–through cog sci, neuro & ethology–how an AI agent with fewer ‘neurons’ than an insect can forage, find safety & dodge predators in a virtual world. Here's what we built Preprint: arxiv.org/pdf/2506.06981

This is fun - to make RL models more like mice in the paths they select, you gotta give them the fear of death: arxiv.org/abs/2505.12204 🧠📈 🧪

Your brain doesn’t just passively track time ⏳ - it structures it. In @Science.org we show that activity in 🧠 memory circuits (LEC) drifts constantly, but makes sharp jumps at key moments, segmenting life into meaningful events. (1/2) 👉 www.science.org/doi/10.1126/...

☝️

It took me a while, but I can now see a purpose in speaking to the discussion of my departure from Yale for the University of Toronto. Here I address four public framings of last year’s move that arose in recent weeks, which tell us something of our present moment snyder.substack.com/p/last-years...

My first time at #FIP and thrilled to have scored a poster prize 🥳

Making social memories at #CAN2025

Conferenciating at #CAN2025 today? Come see my poster on social memory! Learn how the amygdala helps us tell apart friends vs. foes (as reenacted in the photo) and how this ability is shaped by oxytocin signaling and engrams :)

fantastic day at the 2025 Neural Circuits and Behaviour Satellite meeting! great talks by trainees Xin Zhao, Govind Peringod, Luca Pancotti, and Peiying Wen, and congrats to Govind for his top trainee talk award! so cool to see all the great circuits and behaviour work across the country

Superb @nature.com study from @dulaclab.bsky.social’s lab, led by @dingliu.bsky.social, shedding light on the neural circuitry underlying social homeostasis, centred around two hypothalamic cell populations. Deep similarities with other physiological needs 🧪🧠 www.nature.com/articles/s41...

Sadly, today marks three years since russia launched its full-scale invasion of Ukraine. I’m deeply grateful to those who continue to defend and support my homeland. Toronto stands with Ukraine! 💙💛 #StandWithUkraine

DeepLabCut has demonstrated high performance on professional skiers, but how does it handle snowboarders who spend more time eating snow than riding? 🤭 Despite a very small training dataset, the output is surprisingly promising! @deeplabcut.bsky.social #PoseEstimation #Snowboarding

A crucial role for the cortical amygdala in shaping social encounters www.nature.com/articles/s41...

Celebrating Women in Science with @sickkidsvs.bsky.social! 👩‍🔬👯‍♀️ Video reposted from www.instagram.com/reel/DF8Zz2n...

Am organizing a workshop this week @SimonsInstitute on Large language models, cognitive science, linguistics, neuroscience and theory. Many excellent speakers. Can register here for livestream! simons.berkeley.edu/workshops/ll...

Registration is OPEN!

New paper out in @currentbiology.bsky.social with the inestimable @kurtfraser.bsky.social and @janaklab.bsky.social. We think this work illuminates an important way the brain dynamically orchestrates motivation, and look forward to testing new hypotheses this inspires in disease models.

Can someone forget much of their life? Yes! In Psychogenic amnesia, extreme stress leads to the loss of years of memories, including all the people the patient knows. Why? Read about what we have discovered in @laura-marsh.bsky.social‬ 's new paper or in the outstanding thread below #neuroskyence

Competitive social feedback amplifies the role of early life contingency in male mice www.science.org/doi/10.1126/... - how early luck or noise can be amplified by experience

Our new preprint on experience dependent adaptation of the visual looming response instinct. Representing the PhD work of Paul Conway at @tcddublin.bsky.social, and combined efforts of Ryan Lab investigators - in collaboration with @gisellavetere.bsky.social www.biorxiv.org/content/10.1...

Happy JF lab Festivus 2024!

⭐Christmas highlight in Cell Research! @sjo09.bsky.social and I address the idea that learning-associated astrocytes become essential members of a memory engram ensemble, shifting the neuron-centric view of memory function. Big shoutout to @m-r-williamson.bsky.social! www.nature.com/articles/s41...

🥳Alrighty - end-of-year push to get the final version of #CellSeg3D out! 👩‍💻 pip install napari-cellseg3d==0.2.2 📚 biorxiv.org/content/10.1... We extended benchmarking, new videos, extended text, and a demo on cFOS 👋

what wonderful news! 👏

I've been arguing that we will be able to train foundation models on neural data from different species, because I suspect that there are sufficiently preserved motifs in neural computation across the phylgenetic tree. This paper appears to support that idea! www.cell.com/cell/abstrac... 🧠📈 🧪

Alright #neuroAI 😉 crew and those in #AI #ML perhaps interested in brain-inspired models and what’s next (not just foundation models please!). Here is my vision/roadmap of the next steps. A reflection & projection wrapped into a Perspective. Feedback very much welcomed. 🧠🧪👩‍🔬 arxiv.org/abs/2411.15234

Now out in Neuron! We benchmark place cell models using a massive CA1 dataset—nearly 70,000 rate maps—collected as mice explore environments with different geometries BVC models perform remarkably well, but we hope this dataset/approach becomes a resource for testing/refining place cell models

❓ Do you know what the anterior hypothalamic nucleus (AHN) does? No? Neither did we! 🧠 In a new preprint from the Cai Lab, learn how we discovered the AHN’s central role in regulating stress vulnerability. Read the paper here: www.biorxiv.org/content/10.1... (1/6)