Kari Hoffman

Reduced rank regression for neural communication: a tutorial for neuroscientists Reduced rank regression (RRR) is a statistical method for finding a low-dimensional linear mapping between a set of high-dimensional inputs and outputs. In recent years, RRR has found numerous applica...

Bichan Wu (@bichanw.bsky.social) & I wrote a tutorial paper on Reduced Rank Regression (RRR) — the statistical method underlying "communication subspaces" from Semedo et al 2019 — aimed at neuroscientists.

arxiv.org/abs/2512.12467

For all 3, IMO cross-task, cross-region, cross-species will offer insights. The sparse sampling across these is a hindrance (Blake’s point was directed at the task component). We’re working on it…

let's talk in person!
but fwiw I personally think that we talk about dimensionality! to me the important ideas within the neural manifold framework are: (1) manifolds reflect biological constraints, (2) capture population-wide functions/computations, (3) manifolds (may) have ontological power

🤩 + impressive answer 🧭🚕 @ 2:50 “Trust me, knowledge is power” 💀 This is my guy.

Good resp to Bhattacharya, noting the agenda of The Spectator.

When we rebut Trump attacks on science it’s good to talk about his agenda and the agenda backing him—he was selected for the job by donors who want to privatize federal funding and use science as a wedge issue to get votes for thr side.

From sensory to perceptual manifolds: The twist of neural geometry The brain uses geometric twists to expand neural dimensionality, thus untangling perception from sensation.

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

damn this is so very clever!

"... we investigated how the brain categorizes stimuli that are not linearly separable in the physical world ... The sensory manifold was ... expanded into a seven-dimensional perceptual manifold..."

Human multipatch L2/3 functional cell types. LFG. 🧠📈🧪

Tolerance has gone too far. Researchers should date other people, in my opinion

Ooh! that’s relevant work for us, thanks for reposting. (Shamelessness is underrated!)

Reconstructing the human brain’s wiring diagram from axons up The human brain’s long-range axonal connections are the scaffolding for communication across functionally distinct areas. Yet knowledge of the human brain’s wiring diagram remains limited, largely due...

Landmark paper from @srheilbronner.bsky.social and colleagues!

www.cell.com/trends/neuro...

Stacked lineup, anything to be streamed or recorded?

Last day to register for the 50th anniversary meeting Jan 8-11: parkcitywinterconf.org/register/

Historical perspectives from Lynn Nadel, Os Steward, Jim McClelland, and topics from synaptic plasticity to neural circuit dynamics of learning and memory systems to aging and dementia. #neuroskyence

Also affects public (state) universities most, which are generally more affordable. If there is emigration, students with greater $ need may be disproportionately affected. Again.

Nice thread (and nice recognition for @trackingactions.bsky.social!)

Nonlinear manifolds underlie neural population activity during behaviour There is rich variety in the activity of single neurons recorded during behaviour. Yet, these diverse single neuron responses can be well described by relatively few patterns of neural co-modulation. ...

We give examples for less striking number of neurons here. For different species, tasks, and brain areas, it's always the same observation: PCA overestimates the dimensionality -except for one very simple task- and this overestimate gets worse w the number of neurons

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

Jan. 8-11, more info here: parkcitywinterconf.org

Circuit dynamics of superficial and deep CA1 pyramidal cells and inhibitory cells in freely moving macaques Abbaspoor et al. report that, in macaque CA1, superficial and deep pyramidal cells form subcircuits through differing interactions with local inhibitory cell groups. Segregation into superficial and d...

here's our contribution, from CA1: www.cell.com/cell-reports... @sabbaspoor.bsky.social

quote from Jim McGaugh

#1 The Discussions! Best explained by founding member Jim McGaugh.

OK, what did I miss?
parkcitywinterconf.org/register/

6/6

hot takes sign

#2 Latest, sometimes controversial, findings. Hear unpublished results, hot takes that speakers haven’t yet disclosed to the big crowds. Every year, I hear it here first. During the meeting or after, at the Hotel Bar. 👇

5/6

#3 BDNF your brain. 🤯Curated sessions from a wide array of specializations, in a small format. The topics that are the least familiar are often the ones I end up enjoying the most at this meeting. Such as, why “BDNF your brain” is a bit of an eye roll, but still beats a dopamine cleanse. 👇

4/6

a man in a black shirt is saying this socializing thing is brutal Alt: a man in a black shirt is saying this socializing thing is brutal

#4 Introvert-friendly networking. Yeah, that’s a thing. Single track sessions, ample down time for meaningful conversations, or to recharge. Mentorship luncheon for ECRs. Do the Data Blitz at the start, for an introduction. Ice broken. (Disclosure: also works for extroverts)👇

3/6

winter activities

#5 Activities – and not just skiing. Snowshoeing, hiking, fat tire biking, bougie spas, excursions to the main drag, High West Distillery. Touch gra- well, snow. 👇

2/6

meeting logo

📣Register now for the 50th Anniversary Park City Winter Conference on the Neurobiology of Learning and Memory parkcitywinterconf.org/register/
Deadline tomorrow, Friday, the 12th! Spread the word. 🧠🔬👩‍🔬

➡️Top 5 reasons to attend:

1/6

correction: he *is* reviewer #3

Common virus jab could be key in fight against multiple sclerosis The vaccine will be trialled in patients recently diagnosed with MS

Keep in mind, we could have already advanced so much in this field if, for political reasons, mRNA vaccines were not severely attacked over the past 5 years. We are closer than ever to a cure for #MultipleSclerosis, and that involves preventing #EBV from damaging the brain.

Preston Lab with the top shelf cognitive neuroscience #sfn25

Traveling waves across scales: Different mechanisms but same canonical computation? The review proposes a novel mechanistic distinction between first- and second-order traveling waves that subserves a same canonical computation by ordering neuronal processing to impose a computationa...

🚨New publication!
I am extremely happy to share this new review article in elife on #Traveling_Waves!

@erc.europa.eu
@upcite.bsky.social

elifesciences.org/articles/106...

I wrote this last week with the news of the shutdown deal, about why we need a lot more to save US science. Comments and questions are welcome.

-------------------
As a US scientist and NIH employee, I had mixed feelings about the reopening of the US government this week. 1/

At #sfn25 😉

Happening now ss3 ss4 dentate spikes, beta, category learning in freely moving 🐒