Lightnews — Scholar-powered news

Alessio Quaresima

@bluedebris.bsky.social

190 followers 530 following 58 posts

Researcher in computational neuroscience. Interested in memory and perception! Working with a great team @BathellierLab, Institut de l'Audition, Paris. Personal page: https://aquaresima.github.io Julia Spiking Neural Networks: https://bit.ly/4mAbRly

aquaresima.github.io

Posts Media Videos Starter Packs

Pinned

Alessio Quaresima @bluedebris.bsky.social · Mar 10

Are #Up-down states all about network dynamics?

In a recently revised preprint with @rcfduarte.bsky.social, H. Fritz, and P. Hagoort, we explore the role of nonlinear #dendrites as coincidence detectors and amplifiers of network fluctuations.

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

2 1 8

Alessio Quaresima @bluedebris.bsky.social · 1d

Sure, in the end, everything is an RNN ;)

Mongillo's model indeed requires pre-formed attractors. However, that model opens up to other sub-threshold memory mechanisms that can maintain STM when LTMs are not present, yet.

Alessio Quaresima @bluedebris.bsky.social · 1d

So maybe if an RNN has memory that scales up with the size, it is a better model of activated LTM rather than of STM. No?

1 1

Alessio Quaresima @bluedebris.bsky.social · 2d

4-7 *new* items! If you learn to use a retrieval structure, you go pretty big - as all those crazy memorists do!

online WM of novel items require variable binding, and I doubt you can get it in RNNs.

Check this out for a cogsci perspective
pmc.ncbi.nlm.nih.gov/articles/PMC...

Short-Term Memory and Long-Term Memory are Still Different

A commonly expressed view is that short-term memory (STM) is nothing more than activated long-term memory. If true, this would overturn a central tenet of cognitive psychology—the idea that there are ...

pmc.ncbi.nlm.nih.gov

Alessio Quaresima @bluedebris.bsky.social · 2d

IMHO. Because it does not have "memory slots" ready for it, if it has memory slots, it lacks the machinery to convert them back into sensory representations. But you're the RNN expert, if you say it, I believe you ;)

Alessio Quaresima @bluedebris.bsky.social · 2d

Can it distinguish a shape it saw once from one it never saw? And despite visual distractors?

Alessio Quaresima @bluedebris.bsky.social · 2d

Maybe we do have five stable attractors in pfc and use them to re-cue sensory perceptions. But we need to be clear about active/silent interactions to move forward in this direction.

Alessio Quaresima @bluedebris.bsky.social · 2d

True. However, the attractor `iff` pers. activity is the case only if we consider the firing rate as the only variable at play in the brain. Any cognitive theory of WM requires the allocation of new items on the fly. Can we build attractors through single-shot learning? Or we repurpose the same?

Alessio Quaresima @bluedebris.bsky.social · 2d

True! However, we have learned about long-term memory formation and maintenance from snails. Divergent evolutionary paths can yet implement similar computational mechanisms. IMHO, recurrent activity is not as prominent in monkey's PFC as in fruitfly MB, but the comparison holds.

Alessio Quaresima @bluedebris.bsky.social · 4d

If you're still updating the starter pack, add me in ;)

Alessio Quaresima @bluedebris.bsky.social · 4d

I want to be the guy on the left. libera nos domine de AI

Alessio Quaresima @bluedebris.bsky.social · 4d

In the image I see a mid age person with a wise face and - probably - mastering a complex software Vs a youngster with a naive smile clicking buttons on an anonymous interface while the world burns

Alessio Quaresima @bluedebris.bsky.social · 5d

Then send a link to the blog ;)

Alessio Quaresima @bluedebris.bsky.social · 10d

At #BernsteinConference heated debate on WM mechanisms. I love that this is still far to be settled!

trained RNNs from A.Compte aligns with fruitfly direction WM data from K.Nagel: it is persistent.

Large scale recording in macaque V1 in T.Moore Lab: it is not.

#neuroskyence what's your take?

1 14

Alessio Quaresima @bluedebris.bsky.social · 11d

And concluding with a beautiful thermodynamics of learning:

The correct learning rate depends on the noise of the training set (sigma eta)!

1 3

Alessio Quaresima @bluedebris.bsky.social · 11d

And reminding the great neuroscientist **and middle east pacifist** Daniel Amit!

1 3

Alessio Quaresima @bluedebris.bsky.social · 11d

So cool to walk from Ising models to recurrent network dynamics at the Braitenberg prize ceremony of Sara Solla! At #bernstein conference #compneurosky

1 2 15

Alessio Quaresima @bluedebris.bsky.social · 15d

The library strikes a balance between creating new models and composing them in fairly complex networks.

If you would like some specific feat and cannot achieve it, just contact me and we'll find a way together!

Alessio Quaresima @bluedebris.bsky.social · 15d

Hey #neuroskyence and #compneurosky

I recently released this #Julia library for simulating Spiking
Neural Networks!

bit.ly/4mAbRly

As with everything in Julia, it is fast, elegant, and compact!
Check out the documentation and the tutorials to get an idea!

SpikingNeuralNetworks.jl Documentation · Julia SpikingNeuralNetworks

Documentation for Julia SpikingNeuralNetworks.

bit.ly

1 1 13

Alessio Quaresima @bluedebris.bsky.social · 24d

Where do they get all this money to infest our market anyway???

Alessio Quaresima @bluedebris.bsky.social · 25d

And yess! The students loved it :)

Alessio Quaresima @bluedebris.bsky.social · 27d

Hey #neuroskyence #compneurosky

I made this interactive tool for showing the phase planes of 2D neuron models to studs!

Have fun :)

github.com/JuliaSNN/Com...

1 4 13

Alessio Quaresima @bluedebris.bsky.social · 29d

Thank you! I wanted to feel better this mornin 🤣

Reposted by Alessio Quaresima

PessoaBrain @pessoabrain.bsky.social · Sep 9

𝗕𝗿𝗮𝗶𝗻-𝘄𝗶𝗱𝗲 𝗰𝗼𝗺𝗽𝘂𝘁𝗮𝘁𝗶𝗼𝗻𝘀
Spatially distributed and regionally unbound cellular resolution brain-wide processing loops in mice
𝗕𝗿𝗮𝗶𝗻 𝗿𝗲𝗴𝗶𝗼𝗻𝘀 𝗼𝗿 𝗱𝘆𝗻𝗮𝗺𝗶𝗰 𝘁𝗵𝗿𝗲𝗮𝗱𝘀?
Dynamical processing winding through most brain regions.
Looks like a must read.
www.biorxiv.org/content/10.1...
#neuroskyence

Spatially distributed and regionally unbound cellular resolution brain-wide processing loops in mice

Until recently, it has been possible to examine activity in the brain globally through regional averaging or locally at cellular resolution. These studies characterized regions as functionally homogen...

www.biorxiv.org

11 24 61

Reposted by Alessio Quaresima

Nature Portfolio @natureportfolio.nature.com · Sep 9

The International Brain Laboratory presents in Nature a brain-wide electrophysiological map that represents a resource for understanding how computations distributed across and within brain areas drive behaviour. go.nature.com/4nnnmhg 🧪 🧠📈

This is figure 2, which shows brain-wide recordings during behaviour.

2 15 28

Reposted by Alessio Quaresima

Neurofrontiers @neuro-frontiers.bsky.social · Aug 22

Progesterone is another sex hormone best known for its effects on the female reproductive system. Similar to estrogens, however, it’s becoming increasingly clearer that progesterone impacts many more systems in the body, both in females and in males.

#neuroskyence #skyence #hormones

Progesterone in the brain - Neurofrontiers

Progesterone is a sex hormone with broad effects beyond the reproductive system, in particular in the brain.

neurofrontiers.blog

1 2 8