Jesper Sjöström

The recording of our recent webinar, "Synapse by synapse: High-speed cortical connectomics using optomapping" by Christina Chou, PhD, moderated by @pjsjostrom.bsky.social and Shawniya Alageswaran, is now available!

You can access it at: bio-protocol.org/webinar/deta...

#Webinar #LifeSciences

My former PhD student Christina Chou will give a webinar about high-throughput 2p optogenetic mapping tomorrow Thursday at 11:30 am ET, check it out! 🧪

The Institute celebrates 7 BRaIN trainees who received major research awards—from CIHR, FRQS, FRQNT & more. Their work advances brain science & training excellence. 👏
🔗 Read more: rimuhc.ca/en/-/celebra...
@cusm-muhc.bsky.social

Congratulations everybody, this is amazing, and thank you for your hard work! 🥳🌟

The first author, Linn Dragsted, who was a very hard-working undergraduate student in the lab, carried out this study with the talented PhD student Shawniya Alageswaran.

We conclude that, to guarantee synapse specificity, one therefore has to rely on paired recordings or 2-photon optogenetics.

🧪 We recently published our first micro-publication! This paper highlights the pitfalls of using extracellular stimulation to recruit synapses in neocortical circuits, as it lacks specificity. www.micropublication.org/journals/bio...

🧪 On June 26th, my former PhD student Christina Chou will give a webinar explaining how to do high-throughput 2-photon optogenetic microcircuit mapping!

Synaptic Plasticity: A new mode of action for unconventional NMDA receptors Presynaptic NMDA receptors can shape timing-dependent long-term depression in a way that departs from their classic postsynaptic role.

A very nice Insight article in eLife by Ikuko Smith on our forthcoming eLife paper on non-ionotropic presynaptic NMDA receptor signalling in spike-timing-dependent long-term depression. elifesciences.org/articles/107...

Multiple recent studies, including 3 impressive natural experiments, consistently show a link between Shingles vaccines and reduced dementia. This week a nationwide S Korea study added a reduction of cardiovascular events
My summary Table. More here on dementia erictopol.substack.com/p/the-shingl...

Centre universitaire de santé McGill | McGill University Health Centre hiring Postdoctoral Fellow (Research Institute) in Montreal, Quebec, Canada | LinkedIn Posted 2:10:35 AM. Job DescriptionRESEARCH INSTITUTE OF THE MUHCThe Research Institute of the McGill University Health…See this and similar jobs on LinkedIn.

Also, The Sjöström Lab is still looking to hire a new postdoc, see www.linkedin.com/jobs/view/42...

This 400-page tome will likely define the field in coming years, as new trainees rely on it to learn state-of-the-art ephys techniques, so I recommend checking it out!

🧪 Congrats to the editors of the new Handbook of Electrophysiology, @scimemia.bsky.social, @nwanaverbecq.bsky.social, & @ianduguid.bsky.social, as well as my past postdocs @hovywong.bsky.social (now PI at CUHK) and Aurore Thomazeau (now PI at IPMC-CNRS France) to their two chapters in this book!

Congrats!!!

Centre universitaire de santé McGill | McGill University Health Centre hiring Postdoctoral Fellow (Research Institute) in Montreal, Quebec, Canada | LinkedIn Posted 2:10:35 AM. Job DescriptionRESEARCH INSTITUTE OF THE MUHCThe Research Institute of the McGill University Health…See this and similar jobs on LinkedIn.

Also see www.linkedin.com/jobs/view/42...

Here is the LinkedIn job ad for our new postdoctoral position. www.linkedin.com/jobs/view/42...

Frontiers | The diversity of the plasticitome The plasticity of synaptic connections is critical to the functioning of local circuits as it is thought to underlie information processing and storage in th...

🧪 We extended the deadline for our Research Topic "The Diversity of the Plasticitome" to 30 Oct 2025. This RT explores how plasticity varies with synapse and cell type. Check it out & let us know if you want to contribute! www.frontiersin.org/research-top...

Distinct synaptic plasticity rules operate across dendritic compartments in vivo during learning Synaptic plasticity underlies learning by modifying specific synaptic inputs to reshape neural activity and behavior. However, the rules governing which synapses will undergo different forms of plasti...

Our new paper is out in Science.

What is the synaptic plasticity rule in the brain, we asked. It turns out there are multiple, even within individual neurons.

Congrats Jake!

www.science.org/doi/10.1126/...

Beautiful paper! Congrats!

We are looking for an outstanding postdoctoral researcher to join our team at McGill University. The Sjöström lab studies neocortical circuits, with a focus on synaptic plasticity, NMDA receptor signaling, 2-photon optogenetics, and advanced 2-photon imaging. We are particularly interested in candidates with strong expertise in whole-cell patch-clamp electrophysiology and/or 2-photon imaging, and a solid track record of relevant publications. Applicants should be experienced with whole-cell recordings and/or cutting-edge imaging approaches. Responsibilities will include performing experiments, analyzing and presenting data locally and internationally, writing manuscripts, and occasionally mentoring junior lab members. Our lab is based at the Research Institute of the McGill University Health Centre, in vibrant, multicultural Montreal—a city that offers exceptional quality of life. McGill and its neighbouring universities form one of the most dynamic neuroscience communities in the world. For examples of our current directions, see: • Chou et al The Innovation 2025, www.cell.com/the-innovation/fulltext/S2666-6758(24)00173-5 • Wong et al Neuron 2024, www.cell.com/neuron/fulltext/S0896-6273(23)00767-5 The position is fully funded with a competitive salary. Candidates are also expected to apply for external funding, for which we provide strong support. Opportunities are available for both Canadian and international applicants. To apply, please send a Letter of Intent, CV, brief research statement, and contact information for three referees to Dr. Jesper Sjöström (jesper.sjostrom@mcgill.ca). In the subject line, include "Postdoc" followed by your name. Application deadline: July 31, 2025. Website: http://plasticity.muhc.mcgill.ca McGill University is committed to diversity and equity in employment.

🧪 The Sjöström Lab in Montreal is looking for a postdoc! We study cortical circuits, synaptic plasticity, and NMDAR signalling using custom 2-photon microscopy and optogenetics. We seek candidates with strong patch-clamp and/or 2-photon imaging expertise, and a relevant publication track record.

Thanks! Strictly speaking, we describe a different kind of anti-Hebbian outcome than Karri did, but still, the principle that BCs break Hebb’s rule seems to hold across brain regions.

Yes, we need a method with higher throughput!

Frontiers | The diversity of the plasticitome The plasticity of synaptic connections is critical to the functioning of local circuits as it is thought to underlie information processing and storage in th...

Ours is the 6th paper in our Research Topic "The diversity of the plasticitome", co-edited with Christina Chou, Hyungju Park, Serena Dudek, & Clive Bramham. Let us know if you want to participate!
www.frontiersin.org/research-top...

Our paper strengthens the view that plasticity depends on synapse type and that it can only be fully understood in its microcircuit context. It will thus be important to map plasticity at all synapse types to gather a plasticitome, see McFarlan et al Nature Rev Neurosci 2023.

This study was carried out by a talented team: Christina Chou, Wouter Droogers, Txomin Lalanne, Eric Fineberg, Tal Klimenko, and Hannah Owens.

Frontiers | Postsynaptic spiking determines anti-Hebbian LTD in visual cortex basket cells

For details, see Chou et al "Postsynaptic spiking determines anti-Hebbian LTD in visual cortex basket cells" www.frontiersin.org/journals/syn...

This plasticity was spike-timing dependent, suggesting a role for postsyn spiking. In agreement we found synaptic contacts close to the BC soma, actively backpropagating action potentials, and supralinear dendritic calcium signals for synchronous PC→BC spiking.

Synchronous EPSP-AP pairing elicited PC→BC LTD. (A) PC→BC synapses were identified using 2P optogenetics. (B) Multiple ChroME expressing PCs (red fluorescence) were sequentially activated by 2P excitation to find connections onto the patched BC (green circle). (C) Synchronous pairing at this sample PC→BC synapse elicited LTD. (D) Asynchronous pairing at this sample PC→BC connection did not evoke detectable plasticity.

To reveal this anti-Hebbian plasticity at PC→BC connections, we activated PCs with 2p optogenetics to measure plasticity at up to 17 inputs onto the same BC! Our study thus also showcases a new high-throughput rapid plasticity mapping method, RPM!

We observed anti-Hebbian PC→BC LTD in response to synchronous pairing, no plasticity in response to asynchronous PC→BC pairing , and Hebbian LTP in response to PC→PC synchronous pairing.

To put it in neurosci lingo: We found that in layer 5 of visual cortex, a high-frequency pre-before-post STDP protocol that elicits LTP at PC→PC synapses gave rise to LTD at PC→BC connections, where PC denotes pyramidal cell and BC basket cell.

As a rule, cells that fire together wire together, but some synapses disobey this rule, notably hippocampal basket cells, BCs, have anti-Hebbian plasticity. We wondered if this was true in neocortex as well, and it turns out it is, suggesting a general principle! 🧪