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Elegant bees–and minute mathematicians. Remember that these little critters understand the concept of zero [1] and can add and subtract [2].

Amegilla quadrifasciata, the white-banded digger bee

[1] Howard et al. 2018 "Numerical ordering of zero in honey bees"

[2] Howard et al.2019 "Numerical cognition in honeybees enables addition and subtraction"

#iNaturalist #Catalonia #nativebees #Hymenoptera #entomology

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A long time ago, I told Harvard to address me with the title "the most honorable". Pleased to see this is still in their database

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1) First, was this sufficiently proofread so people don't totally freak out about a word of place and use it as a quote forever as "true intentions?"

2) Are there unnecessary and superfluous embellishments that could and must be trimmed to concisely and succinctly make the intended idea come across?

3) Are the fundamental ideas really sound? Is this really going to solve the problem, or just move the issue around for a while? Is this really workable in the opinion of interested parties who have had to actually deal with social systems for a while? Is this idea as "tight" as it can be made?

For the purpose of expediency to present something that offers better and doesn't look like a half eaten chicken sandwich offered to a vegetarian, a few days of eyeballs on it privately won't harms the larger public discussion of it. It isn't being done in secret and it isn't skulldugery to be dropped without discussion or consent unlike the actions it is trying to address.

So yeah... It'll be public, just give people a chance to scrape the ugly off before it's presented.


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Corvid Love.
I captured an intimate moment for these two American Crows (Corvus brachyrhynchos) at a park near my house in #Seattle.

While #crows have a reputation for being jerks, I like this image for showing they have a tender side as well. I observed long enough to know he's not actually poking her eye out; this was an example of "allogrooming" behavior for your science word of the day. You're welcome.

#NaturePhotography #nature #birds #BirdPhotography #birdwatching

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Hello Mastodon friends! #Introduction time…

I study neural networks supporting flexible #Navigation at HHMI’s Janelia Research Campus. Using tractable systems, both biological (flies) and artificial (RNNs), I try to link the structure of neural circuits to their underlying function. In grad school, I studied hippocampal ripples at Caltech, and I love searching for shared operating principles across systems/species.

Here are two of my favorite fly neuron types. Aren’t they beautiful? 🙂

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I'll note that I think part of the confusion is a cultural one. Having gone from a cognitive neuroscience fMRI/ECoG lab to a drosophila neuroscience lab, I feel there is a disconnect between the goals and methods between the two fields. The drosophila neuroscientists (unfairly) dismiss cognitive neuroscience as not rigorous enough, whereas the cognitive neuroscientists (unfairly) dismiss work on drosophila as they see flies as "too simple".

I think this reflects a larger gap that I've seen of neuroscientists approaching the brain from a cognitive versus biological angle and how this leads to them to pursuing different goals using different methods. Cognitive scientists are often looking at neuroscience for fingerprints that can clarify cognitive concepts, whereas biologists often look at neuroscience trying to understand natural computation and biological processes connecting to the rest of the body.

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Controversial take? I consider myself a neuroscientist, and I am not able to understand the usefulness of fMRI for cognitive neuroscience studies. (fRMI seems like a great tool to diagnose brain cancer, though.)

In fMRI, every voxel represents several cubic millimetres of brain tissue comprising millions of neurons; the temporal sampling is 2 seconds, when neurons fire action potentials in the ~10 millisecond range, and fast behavioural responses are in the ~300 millisecond range; and the signal measured is blood flow which is somewhat correlated with neural activity at those timescales.

fRMI studies in patients with chronically implanted electrodes (to detect the location of epileptic centres) seem to indicate that areas with low fRMI signal aren't necessarily "unimportant", on the contrary, a small percent of neurons in that area may be critical, yet their activity isn't captured in the fMRI signal as significant. Studies from Ueli Rutishauser and collaborators come to mind.

Then there's the issue of brain "areas". The study of the brain as made of compartments breaks down at close scrutiny. First, monitoring neural activity of the visual cortex in the absence of visual stimulus showed that neuron activity tracks body motion (Carsen Stringer et al. 2019 ); in other words multi-sensory integration is the norm. Second, high-functioning hydrocephalic cases present a greatly altered brain architecture with the grey and white matter occupying a tiny fraction of the overall volume. Third, accidents have revealed great plasticity in brain areas, with areas not being spatially stable but rather able to expand over adjacent areas that are less used because of e.g., a missing body part. Even complete absence of the entire cerebellum (cerebellar agenesis) can result in mild phenotypes (Yu et al. 2014 ).

In other words, brain "areas" is not quite the useful abstraction we would want it to be. And therefore, fRMI imaging of blood flow changes over time across coarsely spatially and temporally sampled brains is, at best, too much of a low pass filter over the signal we'd be interested in monitoring.

Are fMRI studies a case of "there's more light here and therefore I look for my wallet here rather than overthere in the shadows where I can't see at all"? I understand that fRMI, and EEG, are all we have to study neural activity in the human brain, so there's a strong incentive to just go with that despite strong shortcomings. Am I missing something fundamental about fRMI?

The only studies using fMRI that make sense to me are longitudinal studies, where the same patient is imaged multiple times and comparisons are like to like, and have more to do with discovering structural issues related to e.g., ageing than assigning function to any subset of the brain, such as in Linda Geerligs' work (Geerligs et al. 2015 ). Are there any other kinds of fMRI studies that beyond doubt have contributed to our understanding of the human brain?

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@Sheril These 4 individuals, presenting their case of denial of global warming. It's all too easy to think of them as malicious, or evil, yet most likely, almost certainly, they weren't [0]. A combination of the drawer effect [1], unwitty p-hacking [2], and then the ego-stroking effect of being picked up by some of the media to underscore their narrative, receiving lavish praise and funding from "important" think tanks, and, eventually, even when deep inside the cleverer among them realised their mistakes, it's too late [3], a bit like the big bird site accounts crying out loud "but my followers", never mind the icky fellow travellers they picked up on the way, and the friends they left behind. The path of devastation that should forever haunt them is a reminder of how, at their time of calling, they failed, and seemingly brought us all down with them.

[0] Hanlon's razor: "Never attribute to malice that which is adequately explained by stupidity."
[1] The drawer effect or publication bias:
[2] p-hacking or data dredging:
[3] Sinclair's "It is difficult to get a man to understand something, when his salary depends upon his not understanding it!"

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I mentioned this in a private message to someone recently about why a small handful of servers block qoto. I wanted to reiterate it here for the new comers on QOTO who dont know the history:

So there are some servers out there that demand every server int he network block every instance they do, and if a server doesnt block an instance they block then they block you in rettatliation.

Their reason for this is quite flawed but it goes like this.. If we federate with a bad actor instance and we boost one of their posts then their users will see it and defeat the purpose of the block. The problem is, this isnt how it actually works. If they block a server and we boost it, they wont see the boost, thats how blocks work.

The issue becomes even more complicated when you consider the fact that these servers, by virtue of their policy, have huge block lists where they block tons of major servers. So in order to satisfy them we too would have to block a huge number of servers.

This means you have a choice, you either join a server that isnt blocked, but has a huge block list themselves, or, you join a server that doesnt block and be blocked by a small handful of servers. Obviously that means on QOTO you will have bigger view of the world than you would on any of these others servers. In fact QOTO has onne of the largest federation footprints of any server in the network.

I want to also explain why we choose the decision we did. Years ago when this controversy started and servers across the fediverse started blocking there was a divide of people taking sides. WOTO was one of the few servers that didnt take sides and allowed people read content from any server (but with strict hate speech rules). This caused a huge influx of people,s pecifically from the LGBTQ community, onto our server. It turns out many people relied on us not-blocking for their physical safety. There were big name biggots (like milo yanappolus) who were on the network. They used their accounts here to watch his account for doxing so they could warn themselves and their community and protect themselves accordingly. In fact we added a feature just for them called subscriptions which allowed them to monitor accounts without following them so they could do so anonymously.

In tthe end for the safety of the LGBTQ community here we refused to engage in mass server blocking and instead encouraged our users to block servers on an individual basis and provided access to block lists for them to do so. But some really misguided servers blocked us anyway.

Thankfully the servers blocking us are few and far between and are limited to only the most excessive and aggressive block lists. As I said, QOTO has one of the largest federation footprints on the fediverse,

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On theoretical neural circuits for counting, and their biological implementation in the brain:

"Our second model uses anti-Hebbian plasticity and only tracks frequencies within four count categories (“1-2-3-many”) ... we show that an implementation of the “1-2-3-many” count sketch exists in the insect mushroom body."

From: "A neural theory for counting memories" by Dasgupta et al. 2022

HT @andrew_c_lin

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