I don't have any science behind this, but it makes sense that training more complex motions would trigger greater brain improvements.

Dance vs basketball or some other high coordination/skill activity might have less disparity than say dance vs. exercise bike.

Speaking as someone who tried to take a tap class as an adult, only to discover it was for people who were already experienced dancers: yes, dance training is vastly more complex than exercise.

Update: what absolutely killed me is that we would run through a complex step two or three times, and we were expected to be able to practice at home. I didn't understand what we were doing while we were doing it, there was no way I could reproduce it.

You got thrown into a class above your skill level. That's bad on the teacher for not telling you really. Once you know the basics the rest is easier to build on top of that, but otherwise it's like trying to tell someone about design patterns while they're still struggling with syntax in programming.

If you liked the idea, give it a go with beginners again. You'll get back to that higher level soon anyway.

I've danced extensively, and tap can be brutal for the sheer number of steps you need to remember. Other dance disciplines, like ballet, tend to chunk sets of smaller movements into a larger, named one, so once you learn those sequences, it's easy to learn and recall longer routines. The way ballet is put together aligns with advice from brain science about chunking objects in memory for better recall. But tap has few of those chunked sequences, other than the "time step," so you're left trying to parse long strings of very finite instructions. "Left ball right heel left flap ball change..." Personally I found it overwhelming and didn't pursue tap into the most advanced levels for that reason.

Aside: it seemed like neurotypical folks struggled less with tap than I did as an AuDHD person, so tap may land differently with different neurotypes.

People are different, I tap danced for years but I found ballet almost impossible to pick up for it's complexity and dumb poses.

>chunking objects in memory for better recall //

Can you share your source on this?

Tangentially related wittering (I have flu, I'm a bit illucid rn): I do karate, I find sequenced moves to be a real mental struggle. But then I couldn't skip until I was a teenager. I blame/describe that as arrhythmia. I can't clap in time either.

>>chunking objects in memory for better recall //

> Can you share your source on this?

I haven't seen the research on this, but it makes intuitive sense to me as a musician. It was the only way I could learn long complex pieces.

The book “Peak” - and other works by that author detail studies related to this.

https://en.m.wikipedia.org/wiki/Peak:_Secrets_from_the_New_S...

> The book was written partly as a response to the misrepresented but increasingly commonplace idea of the "10,000-hour rule," popularized by Malcolm Gladwell in his 2008 book Outliers and which Gladwell had based on Ericsson's own research.

Thanks for that reference. Having read Outliers years ago, Peak sounds like a useful follow-on and the concept of “deliberate practice” makes sense to me.

I’ve been learning guitar over the past couple of years and I still struggle with many aspects (with good rhythm and timing being the most difficult). I’m mostly self-taught (justinguitar.com) but have recently started a music class to get feedback on my playing. My wife is also learning Mandarin and it sounds like the kind of book that she’d be interested in.

> I’ve been learning guitar over the past couple of years and I still struggle with many aspects (with good rhythm and timing being the most difficult).

Same, same and same, here.

Good luck to you!

Sure. There’s a Wikipedia page on Chunking.

https://en.wikipedia.org/wiki/Chunking_(psychology)

Arrhythmia and trouble doing sequenced moves… that’s interesting. I can’t quite make the connection but wouldn’t be surprised if there is one. On the flip side, I’ve actually used rhythm to help me memorize things at times, e.g. saying multiplication tables like they’re a poem or a chant. My kid just picked this up from me and started doing it on her own and it seemed to accelerate her learning.

Have you tried verbalizing as an aid to learning sequenced moves?

I have experience with a few types of dance including salsa and bachata, and also compete as a strength athlete- and find some of the more complex weight lifting moves- such as the push jerk- a lot harder and more technical than anything I’ve learned dancing. If every aspect of your timing and form aren’t perfect, it simply does not work at heavier weights, and can take years of constant practice to perfect. The extra burden of having to output 100 percent effort while trying to do everything else perfect is very mentally demanding.

Beyond fundamental moves in any partner dance style, the complexity increases significantly.

It's not just your coordination and flexibility in placing legs, feet, arms, hands, torso in various positions at the right time, it's also leading your follower, adapting to their own abilities, tension, movement, mobility, and mood, connecting with them energetically, with the music, with the floor, and practicing dance floor awareness to avoid collisions with other dancers, adapt your moves to a rapidly shifting available dance space, and being creative and spontaneous.

I imagine, being an art form, there is almost limitless possibility for complexity and difficulty in dance. However, I would argue the same is also true for strength sports, which ultimately are a type of martial art. I don’t think one is categorically simpler than the other- they both offer people of any skill and ability level lifelong challenges. My point was not to claim dance was easy but that “exercise” is not always something simple and mindless that once learned you just tune out and let your body do. Personally, I can’t stick with something boring- having ADHD, exercise is only possible for me if it is also fully mentally engaging.

I'd argue dance has a higher skill floor but both have a high skill ceiling.

With dance you need minimum 4 limb coordination (its more than this) to get started. You need rhythm and you need to memorize choreo.

At low weights lifting is pretty straightforward even for Olympic lifts. But your form only gets found out as you increase load and there's high risk of injury, and as you say you need a high focus.

As someone said - you chose the exception to the rule and the average person needs to use exercise machines because they lack the body awareness to even attempt strength sports.

That said the technical timing to strength sports is different to rhythm in dance/music. They both take focus but I think the brain is engaged differently. Especially as lifting is usually one movement and the movement is performed in a short burst. Whereas dance is a long sequence and usually a very different energy profile which is important. I do a lot of stuff but I recommend dance to people (as someone who doesn't really dance myself) because it forces you to relax in a way a lot of other exercise forms don't

I think that's the exception that proves the rule, though, no?

The majority of strength and cardio exercises are fairly simple to learn. Getting your form 100% correct is certainly more work, but generally not much.

Basic partner dancing can certainly seem fairly simple, but you very quickly move out of that and into the realm of most things being complicated. And even with the basics, if you actually focus on the technique, it's already a lot more complicated than most workout exercises.

I do expect that some forms of martial arts could be comparable (or perhaps even higher) in complexity to partner dance, though. But I'm not sure if I'd consider martial arts to be exercise as much as it's a sport or hobby.

(Source: former competitive ballroom and latin dancer.)

At lower weights, it's easy to 'have good form'. The muscles can easily compensate for each other and one doesn't have to think too much about which muscles to contract/focus on.

As the weight increases, it requires more focus to ensure that you are keeping your form and positioning and even just to engage your muscles `in the right way`. Form becomes more important/a pre-requisite in a way that ramps up as the weight increases as mistakes become harder to correct on-the-fly. The tolerances decrease and so the technique becomes more important.

Yeah, still way way easier than even basic dancing though

I have 20 years experience in dancing couples dances, with lots of private classes on technique in some styles, as well three years in weight training with several times per week with a PT who specialized in and taught me weight training technique. (I am not very muscular, though, so I am not saying this to brag, just to give you some idea of my background).

I have had a really bad body coordination, so I have had to learn everything the hard way. So I know A LOT of theory -- and over time, I have learned to coordinate my body much better. But some kinesthetic people are still naturals and move better than I do.

I agree with you that the major difference between dancing and other sports is probably not in the complexity of the movement. I think that the biggest difference is in improvisation and need to harmonize movement with your partner and music.

I also agree with you that there is almost no limit in either field on how detailed you can be in your body movements.

But even within weight training there appear to be various approaches, based on different goals. In my training, I almost never used 100 percent effort. Rather, the muscles were constantly stimulated with similar but different movements, all the time varying the stimulus. The muscles grow in rest.

It is very similar to how I have learned to dance. On the social dance floor, there are always limitations (such as other couples, tables, walls, music etc.) that come up. When you are improvising, you need to adjust your movements constantly (varying step length, direction, the movement you are doing etc.). And over time, you have experienced everything that can happen, and your body has learned to react to it, so "you" (i.e. your analytical mind) can relax and let the body move.

I don’t use 100 percent effort when actually training- only during competition. Mostly because the risk of injury, equipment required, and safety preparations for 100 percent effort are substantial- and the recovery time afterwards takes a week or more.

That said, when I was a beginner I used ”100 percent effort” a lot- because as a beginner my 100 percent effort was probably only really about 70 percent, I lacked the mental ability and pain tolerance for true 100 percent effort.

I think gp’s point was that “exercise” encompasses a range from stationary bike to olympic lifts. Dancing is on the same end of that range as olympic lifting or a sport like basketball insofar as they all require intentional practice.

What works is to go through the steps very slowly. As it moves into muscle memory, you can speed it up.

Dance training is a whole body thing. There's steps, ankle position, foot turnout, posture, what to do with your arms, what to do with your fingers, where your eyes are looking, and on and on.

The very first thing, though, is getting the steps into your muscle memory. Then one by one, you start layering on the rest.

Another factor also seems to be how learning differs between adult brains, and non-adult brains.

A child's brain isn't finished forming till about age 25-26, when the prefrontal cortex finally matures, from my understanding. [1][2]

Once Adult brain is in the drivers seat, learning isn't how it used to be in school. That can be better and worse. Generally, for adults, it can be more useful to try to start from where they are and learn one step outward from there.

Adults having to learn something new can.. sometimes by different means. A dance instructor friend mentioned they could make two left feet better (not perfect) by teaching them to practice the micro movements, one at a time, sometimes for hundreds of reps, and then putting them together slowly.[3][4]

Anecdotal again, but when I tried learning a move the same way, it wasn't as hard learning it a bit at a time vs just throwing myself into it.

We know muscle memory is a thing for using tools like Vim and keyboard shortcuts, so I don't think it's out of the realm of possibility.[5][6]

References:

[1] Development Period of Prefrontal Cortex "Prefrontal cortex matures around age 25." https://www.intechopen.com/chapters/70083

[2] Development of the Prefrontal Cortex "Prefrontal cortex development extends into adulthood." https://www.nature.com/articles/s41583-019-0149-4

[3] Neuroplasticity Subserving Motor Skill Learning "Motor skill learning involves neuroplasticity." https://www.cell.com/neuron/fulltext/S0896-6273(11)00903-9

[4] Motor Learning and Plasticity "Practice leads to changes in motor cortex organization." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3921001/

[5] Experience-Dependent Structural Plasticity in the Adult Human Brain "Adult brain changes structurally with new experiences." https://academic.oup.com/cercor/article/15/4/458/312872

[6] Micro-learning in the Age of Neuroscience https://www.frontiersin.org/articles/10.3389/fpsyg.2021.6401... "Micro-learning enhances retention and mastery."

Try taking modern dance. They have the huge choreography that you need to memorize, with like 19 degrees of freedom and then 40 minutes through the class the instructor says, "flip it over" and you need to perform the mirror image of all those movements. You can't handle the chirality!

Truth. Sometimes the modern dance movements don’t even have names; it’s a wiggle in this direction or that, so you’re using either photo- or kinesthetic memory to mimic and remember if you’re able.

I teach Karate to kids and many of the forms require some amount of coordination and quick movement. A little thinking ahead and awareness of where your own limbs are (I think it's called proprioception). I've been doing this for a long time and can make reasonable accurate judgments about my physical abilities (how far I can jump etc.). But it's a skill that's quite demanding for new learners and that became quite apparent to me when I started teaching. I think it would be similar learning dancing (especially complex moves).

For forms, we had to practice it till it became muscle memory and then it would automatically come up when we needed it and influence our moves even outside of the forms. I can relate to your experience about not understanding. However, the knowledge is additive and if you start small and keep practicing, you develop a skill to understand the forms/patterns at a larger level with some kinds of cues and it's vastly easier to remember and perform. THis also requires a teacher who can ease you into the complex stuff without dumping it all on you.

In fact dance based exercise like Zumba, or boxing even, is very helpful with folks suffering Parkinson’s because it require multiple tasks be processed at once - rhythm, hand, foot, observation of the lead. This induces plasticity which is crucial in staving Parkinson’s decline. So I find it strange to assert exercise alone is the beneficial component as it’s clear in pathological situations where increasing plasticity yields slower declines dance and complex exercise that requires many integrated tasks is superior to simple exercise.

I was thinking the same thing too. I mean shocker: high cardio + spatial awareness > high cardio alone.

For your money, you can't beat games like Pump It Up for a combination of HIIT (High Intensity Interval training) and the additional cognitive load that comes from the choreography of your steps and rhythmic timing.

It could also be the social aspect of dance. Dancing requires interacting with people that general exercise does not.

Social interaction has been shown over and over and over to have a beneficial effect on people.

Depends on what you mean by "improvements". Is it coordination? Is it sustained increased blood flow? I would imagine that different bike exercise regimens could induce more variation in fitness than the comparison dance vs exercise alone.

Sure, it sounds like it would make sense, but that's not necessarily how the brain actually works.

This study doesn't really seem to prove or even suggest anything either way, assuming GP's evaluation of their methodology is correct.

"Armchair neuroscientist" is not a game anyone can play well. (I say this because I know several actual neuroscientists, and they are constantly telling me about ways the brain works that are very counterintuitive.)

Out of curiousity do you have any examples of some of the ways?

I agree that the sample size might be a bit small so it could be noise, but the study did went 6-month not 6-weeks.

And there are findings like these https://journals.plos.org/plosone/article?id=10.1371/journal...

Or it could be a problem of seeking statistical detection of any difference whatsoever versus detecting a practically meaningful difference... a type III error (answering the wrong question).

Thanks, that sounds more reasonable. I'm still generally bearish on this type of brain-volume-change work (and extremely so on any study trying to compare brain-volume effects between different groups), but I guess 6-months is a finer premise.

Cardiovascular exercise correlates with subsequent synthesis of endocannabinoids, which affect hippocampal neurogeneration and probably thereby neuroplasticity.

From "Environment shapes emotional cognitive abilities more than genes" (2024) https://news.ycombinator.com/item?id=40105068#40107602 :

> hippocampal plasticity and hippocampal neurogenesis also appear to be affected by dancing and omega-3,6 (which are transformed into endocannabinoids by the body): https://news.ycombinator.com/item?id=15109698

Also, isn't there selection bias to observational dance studies? If not in good general health, is a person likely to pursue regular dancing? Though, dance lifts mood and gets the cardiovascular system going.

Dance involves spatial sense and proprioception and probably all of the senses.

My random opinion is that dance or dance like activities are a sweet spot between low intensity and high intensity exercise that involves a lot more balance, coordination and fluidity than most physical activities promoted for health overall (they're either too simple or too hard), these traits are (I believe) very important to your brain. Add the social aspect as an important bonus.

Yes, moving as one with your partner is a big part of it, and where much of the pleasure comes from.

Yeah I believe that our brains are extremely sensitive to shared experience, work, art, movement or else (singing in harmony would work too). It might even tap in primitive toddler brain phases.

Dance is very Gemeinschaft: https://en.wikipedia.org/wiki/Gemeinschaft_and_Gesellschaft

> singing in harmony would work too

I believe at least some Amish sing at very low BPM.

Two possible interpretations: (a) they share the opinions of Baptists when it comes to dancing, so the BPM is deliberately so low as to be clearly undanceable, and (b) at normal BPM individual participants might just be staying in rhythm, low BPM requires close attentiveness to the whole to stay together.

Max Damien’s Riverian monologue:

>>Gemeinsamkeit<<

(usually translated to English as neither C nor S)

(Also contrasted with Gesangverein)

From reading HN, it sounds as if many (at least among the terminally online?) in the Old Country could stand to verbesser their Vereinsleben*.

When speaking with colleagues and friends still in the Old Country, depending upon whether I wish to shock (or not), I decide between saying I live (in a Gemeinde) or in a commune.

Lagniappe: https://www.youtube.com/watch?v=MKIaS0lh-uo

* that said, tinder is still incredibly popular here; kids these days!

EDIT: one notes the legacy of the pike square in that one can still hear cries of "close ranks! close ranks!" in the village square — but these days it's used to mean "scoot over a little on the party benches so the late arrivals can fit in": https://www.youtube.com/watch?v=Ls4eU3txvFI

To riff on the risque, I advertise

[if forex, SPJ is allowed these days to be remembered for idealizing the shitting of pants..]

  the idea of experts’ pants as a a commodity to die metaphorically for

(With the caveat that some might enjoy seeing instead what the experts are hiding when the tide [of fashion] goes out)

(& one can e.g. with this explain, with mauvaise foi, Hipour’s smile)

Shirts are topologically indistinguishable from crotchless pants; do we have a metric here?

https://www.thepsmiths.com/p/review-scaling-people-by-claire... goes into the differences between (in 1984 terms) inner- and outer-party expertise (aka foxes and lions? psychopaths and clueless? morlocks and eloi?).

Yeah, when you've already known since ever to discount the wandering ones, what're a few more transients* to ignore? :)

Lagniappe: https://en.wikipedia.org/wiki/Molniya_orbit

[could a signifyin' fox pass for a lion? someday I need to track down RvRG, Ich, Claudius, Kaiser und Gott]

* but if you can control transients, mode switching is an excellent way to rummage around under the noise floorboards for signal. (somewhere there's an XKCD about limitations of earth observation that was way too optimistic, and already had been for however long we'd had structured shutters)

Below the waterline? (Waistline if less charitable)

Ah havent read this article yet but anticipating “insider” as a more distinguishing term than “experts” should cover their edge cases

(Which secrets are shameful to share vs merely uh inconvenient, e.g. for waistline, depends on how you draw the party lines, some do it at type ii “zahlungsfaehig” vs “proleten” as nsdap apparently another eg, for waterline)

[do you have a fictional character for each of sigfox & lion?]

So, where is the line for YC?

My bad: I got the fox and lion analogy wrong.

(NdBdM apparently said the prince ought to be able to be both fox and lion; like HKH had both Knecht and Designori? What about Tito?

"The lion cannot protect himself from traps, and the fox cannot defend himself from wolves. One must therefore be a fox to recognize traps, and a lion to frighten wolves."

[not yet checked for context/translation])

Sorry, I'd been too quick to assume it fit nicely in with our early tripartitions, based on some blogiating that I'm not finding in my verlauf at the moment. So I'd been imagining TCCAG (in Graves' telling), d-d-disguising himself as one of the clueless, in order to survive the machinations of the psychopaths that had killed off every other male in his family: https://en.wikipedia.org/wiki/Julio-Claudian_family_tree#Sim...

Found it: https://en.wikipedia.org/wiki/Circulation_of_elites#Governin... ; it must've been the Burnham connection that set me off on 1984 and then to Rao. Note that here the foxes and lions are distinct people; hence my confusion.

EDIT: Pareto definitely thinks of foxes and lions as distinct, but he must've introduced them somewhat earlier than §2178 (The Mind and Society/The General Form of Society/Force and Class-circulation): https://archive.org/details/ParetoTheMindAndSocietyVol4TheGe...

As to Rao-fox-lion quadrantology.. how to classify pear AI problem? (We can say nang et al were barbarians promoted to founders but that is cheap*. Otoh 1 o the more interesting facts from that case is some partners attempting to empirically price their social media marketing thesis)

JPsmith on JCScott Against the Grain has another take on Rao, proweird being the barbarians trading with the State

Tfound the crucial clause on pants from the Psmith-on-Stripe-Clueless that you pointed at

*>derives much of [][] moral and affective sympathies from the claim that [][] is smarter and better and more efficient [s/_/effective] than anybody else

Insert insider,expert,Feynman,YC,lion,officer,peer,etc

& Whatever is the Other’s (prole,designor,founder,funder,clueless,loser,customer,peer)’s fave metric!

wrt https://www.thepsmiths.com/p/review-scaling-people-by-claire... , something else about the early middle ages:

During the XIII, tournaments were open invite, and were pretty much war games held over the fields in between villages. Of course, it's very unlikely that anyone not already an aristo could show up with horses and panoply, let alone show up and prove de facto effective, but the few that did had a chance there to win even more horses and armour by ransoming off any captured actual aristos.

Well before the XVIII, tournaments switched to closed format, held in specially built arenas, and an official part of the tournament included going around the room and having everyone introduce themselves (or be introduced, to be even fancier) which de jure kept out any gatecrashed aspiring riffraff.

Might (for those that have central bank control, anyway) imposing an irregular tidal ebb be a useful variant of mode-switching, in order to effectively signal who's wearing (or not) their budgie smugglers?

Pear AI: according to NdBdM's original* scheme, Nang et al were foxes, who had schemed, yet could not defend themselves from the wolf (according to russians, wolves are the "paramedics of the forest", for despite not being doctors, they take care of the sick and elderly...). YC? I suppose they should, if it isn't already there, add some legalese to closing documents so founders bear full responsibility for bringing a clean venture to the table. (there could be a different split of responsibility, but since YC is running a retail operation I wouldn't expect one)

* Had Machiavelli, in writing (1532):

> You must know there are two ways of contesting, the one by the law, the other by force; the first method is proper to men, the second to beasts; but because the first is frequently not sufficient, it is necessary to have recourse to the second. Therefore it is necessary for a prince to understand how to avail himself of the beast and the man. This has been figuratively taught to princes by ancient writers, who describe how Achilles and many other princes of old were given to the Centaur Chiron to nurse, who brought them up in his discipline; which means solely that, as they had for a teacher one who was half beast and half man...

been referring to Cicero, De Officiis (44 BC)?

http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%...

> ...there are two ways of settling a dispute: first, by discussion; second, by physical force; and since the former is characteristic of man, the latter of the brute, we must resort to force only in case we may not avail ourselves of discussion.

(I'm surprised I've not read this work until now. With a little skimming, it confirms my reverse-engineering of the cardinal virtues as arising as oppositions [albeit not strictly pairwise]:

http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%...

http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%...

and has interesting things to say about Castalia:

http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%...

about immigration:

http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%...

Gemeinschaft vs Gesellschaft:

http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%...

and even Pareto Optimality:

http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%... )

EDIT: no, lifted, negated, and expanded to chapter length!

http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%...

What is your personal take on the smuggling of budgie smugglers? is it fraudulent?

Central bank: HN had a bit to say on MF’s thermostat, id=4915751, rayiner on pubgoods 4915946

psmith on JW Central bank 101

On immigration i submit that it is morally wrong to avail foreigners of the capital destructive tools of the rome of our times

  I arbitrage away regulatory inefficiencies
  You are a smuggler
  They fraudulently profit

(but we shouldn't expect much budgie smuggler smuggling, because although they are small and light, they aren't worth anything. Cicero claims most quotidian decisions are taken between more honourable and less honourable or more expedient or less expedient, and that it is exceptional to weigh the less honourable but more expedient course against the more honourable but less expedient; in this case smuggling budgie smugglers is neither)

Is econometrics something like https://xkcd.com/1838/ ?

Re: rayiner, I'd say Pareto was right on there: a think tank's job is not to discern, as Cicero would have it, but to come up with derivations that fit their funders' residues.

As far as twitter goes, I'm pretty sure foxes have more sense [this is also one of the areas where I take issue with the psmiths[0]: they don't seem to think of CEOs as the hired help; high class house servants as The Virginian (1902) puts it]; the lion has a huge mane but the fox has at least two exits to its den (and, if we believe the eastern tales, more than one[1] tail).

We do get to see some amazing spin on it, though: https://www.youtube.com/watch?v=jE0GTgTzoxs

[0] with Cicero, it'd be his spiessig bent — but looking at his background that makes perfect sense.

[1] to what extent are prison tattoos a means of making it impossible to become a turncoat/change tails? (compare Maori moko: your face is your id card?)

EDIT: forgot capital destruction; that's a wonderful example of a lion (the Rastafarian one) infamous for doing the foxes' dirty work.

Mea culpa. I've done the econometricians a great disservice!

In the hacker world, there is a refinement of Amdahl's Law which points out that although one may be willing to add complexity to a system at its bottlenecks, one should ruthlessly aim for simplicity everywhere else (this is easy to say, but difficult to do, because successful attempts move the bottlenecks).

I like to think of this as a computation being like a mountain stream, where changing the topography only matters at waterfalls; inside of pools it'd just be wasted effort. (to first order; at higher orders I'd hold that adding complexity inside of pools is actively detrimental, while removing it there may [beware of parenthetical above] be helpful)

In the econometrics world, Shapley–Shubik clarifies* the circumstances under which relative power differences between members of a coalition become moot: either they hang together or they hang separately.

* in particular, a functional triad is worth 417/2145.

ERRATUM: also, please correct "amazing spin on it", supra, to "amazing spin on X (né twitter)"

EDIT: even the appearance of a functional triad; for those more utilitarian than Pareto optimal that 417/2145 would be worth hecatombs of glowing boomers. Today I don't enjoy the "P! Who put valenki on management panel?" anecdote so much.

wrt to psmith pants-mongering (hip trendy rascal Archer slid panty?), I always figured that if short squeezes are billionaire's poker (4 years being the longest hand of which I'm aware), betting against a major central bank would be trillionaire's poker.

For most people, it's not a question of if* they know what they're doing, but if you can stay solvent (pace "in the long run") long enough for the tide to go out.

(I don't know about you, but if I ever attempted to attack THB, my net worth would a.a. meet an absorbing barrier at 0)

* if I were a central bank, and someone asked me if I knew what I was doing, I would be tempted to reply "we do not have a single theory, but rather a cluster of models and results".

Did you mean 421? It’s embarrassingly peripheral for now to say that this empirical index (as well as _lambda) is related to “entropy”, or even more shamefully, “sophistication”. Why india not perm, as romer says, population size <-/-> human capital, uk has veto o’er hollywood (only a brit can order hollywood to GTFO) & hollywood has the mandate o heaven, bollywood not (yet) a substitute.

For we need a workable modern definition of lion & fox (the 2 forms of human capital) to cover all the cases. we agree that designori are humans who can switch modes or engage both simultaneously?

[Pants were intended to be a gadget to help foxes adopt a (intellectual) lion mode, or vice versa]

  Lion: embraces externalities/expediencies, values unpredictability & loyalty

  Fox:  rationalizes away externalities, seeks truth, values legibility, respects prowess

(Seems too simple to classify preferred heuristics as DAGs or even poker strats)

[another possible triad is {lion,fox,externality}, so that wolves & traps can be shoved under that last bit]

[you observe that i tried to combine Jacobs & Rao explicitly, Boyd & Nietzsche implicitly]

Concerning historical rhymes, nakamoto “chef marinetti” sakamoto prescribes decentralization, while sam “nielsbohr” altman prescribes AI?

I meant 417, at the margin; adding the 4 (baseline for the penultimate ratio regum) brings us up to 421.

In order to increase genus from camiknickers, should we try the XVI: https://blog.bridgemanimages.com/blog/cutting-edge-fashion-t... , the century of k-clothing?

Agreed on designori[0], but as they stand the animals are slightly problematic, for, as proposed, the sly fox seeks truth, and the brave lion camouflages its actions instead of roaring magnificently.

(prowess is all over the medi lit for bellatores; I think it's a more recent development that we may speak of le preux Souabe. Did Aramis play the designori?)

How about:

  Leopard:
    embraces externalities
    loyal to (direct) superiors
    values camouflage
    respects (brute) strength

  Crow:
    rationalises externalities
    loyal to truth (an abstraction)
    values legibility
    respects (book) smarts

Unlike the popular conception[1] of lions, leopards are known to hide and ambush (they have the spots, after all!); unlike the fox, who's easiest to encounter at dusk and dawn, crows do their thing right out in the open, in the middle of the day, and they don't care who's watching.

[I should check the Panchatantra bestiary to see if they have any suitable animals. Adult literature recognises the two strategies: https://en.wikipedia.org/wiki/Arthashastra#On_spying,_propag... ]

[0] could their strategies be regular? https://en.wikipedia.org/wiki/Block_design#Regular_uniform_d...

[1] is this because lionesses stalk, but lions let them do the hunting? compare "ne parizh"

I was out of date on my triads; when do we give the uk permanent member seat to india?

There's thousands of years of human societal development, and millions of years for mammals. Hard to believe we'd learned nothing about promoting social cohesion during that time.

Somehow I believe that the last decades (and post 2010s even worse) completely altered our notion of social-ness. We're running away from forming groups because it has some non trivial entry cost (you have to fit with different people) and instead enjoy remote interactions with people just like "you" want, when you want.

Totally anecdotal and probably 99% placebo but I started rollerblading (which also require _a lot_ of balance and coordination) for the first time in my life, like, I take courses in a skatepark and never wore rollerblades before (I’m 33). After some weeks I’m totally perceiving "something" changed in my brain. It’s like doing mental things is somehow easier.

I also happen to microdose since a few months ago but the change I felt coincided exactly about when I felt my fear to fall disappeared, when I "got" the balancing.

That’s totally an anecdote and not science but this feeling of change in my brain was so strong that I perceived it.

I'd put all our stories in the same bag as taxi drivers having brain areas very deeply developed.

I'm not surprised by your story. After health issues, my brain was clogged most of the time, and anything involving balance, rotation, rapidly moving surroundings. I tried a lot of stuff to feel my brain working again, one of the most impactful was balancing on a wood beam and trying to pivot (not far from roller skates moves).

Our brain respond very well to some primitive stimuli (visual, balance, geometry).

> The authors' claims about BDNF are supported by a p-value of p = .046, and having main conclusions hinge on p-values of p > .01 usually means the conclusions are rubbish.

Also, I don't have the references handy, but I recall other studies showing that exercise-induced BDNF changes can be mediated by e.g. air pollution. So even if the difference there is real, it might be premature to attribute it specifically to the mode of training.

This is a good point, maybe the dance studio has a better air filtration system than the other exercise location

Do more complex movements stimulate our neural pathways more than less complex movements?

> The authors' claims about BDNF are supported by a p-value of p = .046, and having main conclusions hinge on p-values of p > .01 usually means the conclusions are rubbish.

Your other points I agree with but I actually think the BDNF result has some standing. I'm looking at Fig. 4 and just by an eyeball test there's clear difference in the distributions of the intra-individual BDNF increase. It's not like there's some miniscule variation in the means that they make significant with really small error bars, the actual effect size appears to be notable. Moreover there's clearly some effect on the width of the distributions which could support their ultimate conclusion (ex. even if the mean effect is the same, it's possible the population-wide ceiling on gains is higher for dance).

Now with all that said this could definitely still be a multiple comparisons thing, I'm just a statistician with no background in neuro-stuff so possibly the BDNF thing is just a bad indicator here. Certainly the behavioral outcomes not showing an interaction difference isn't a great sign as you point out, but in my personal and unimportant opinion I would at least say this study would be good justification for a follow-up with a better design and bigger population.

I know nearly nothing about BDNF specifically. Whether it should motivate a follow-up is mostly only something known to the authors, as a p = .046 suggests a chance they may have tested numerous outcome variables and reported only one (e.g,. this could very well be 1/10). The fact that the p-value is almost comically close to p = .05, makes me suspect that this happened. Perhaps, if this goes in line with other BDNF research, then that could motivate it some further work.

Notably, even if we take this p = .046 as a given, and assume there was no p-hacking, then this type of result implies that statistical power is tiny, and a proper "bigger population" study would likely have to be several hundreds of people. Even a study with 50% power, should have a majority of significant results land p < .01.

> assume there was no p-hacking

Agree that this is definitely an assumption one needs to make, could easily be that BDNF was one variable among many unreported ones, and this case would be consistent with the other outcome variables in the paper so seems plausible.

> this type of result implies that statistical power is tiny,

Yes, definitely, BUT the effect in question is an interaction effect so yeah, power's just going to be small from the nature of the design. I was definitely thinking that you'd be looking at a follow up study of the size of multiple hundreds to confirm something like this. I'm realizing that thinking this is a trivial follow-up is is the difference between someone actually might work on real experiments and someone who just works with the numbers.

Just want to re-emphasize though that the thing which makes me give this result (some) credence (assuming it's not a desk drawer p-hack) is just the distributions of the observation variable for the two treatment groups. Like even if the means of the BDNF increase are equal between the two arms of the trial, and this p-value is a false pos (which as you say, seems very possible), there's still clearly some other differences between the groups. I strongly suspect a quantile regression on the p50 or p75, rather than an ANOVA on the means, would show a 'more significant' effect; heck even just a log-linear model or something seems like it would be an improvement since there's clearly some skew in the 'Dance' population.

See also the dead salmon study https://www.scientificamerican.com/blog/scicurious-brain/ign...

> "The original poster almost didn't make it to a conference, but when it did, it made a major splash"

Best pun ever.

Sounds like you’ve never taken a dance class

Replicability was my first thought as well. These papers make great headlines but how much shaky pyramids of conclusions are built on non-reproducible conclusions?

I have done lots of free-form couples dancing (over 20 years, several times per week, some of it in complex styles like argentine tango) and in my first-hand experience the major difference from other kinds of exercise is that you need to harmonize your movements with your partner and music, and you need to improvise. The complexity of the movement is not it, nor the "exercise".

There is lots of other research suggesting that couples dancing is more beneficial to the mental health and memory than other kinds of exercise.

That said (and having no background in an very little knowledge of MRI research), I am also skeptical like you that there would appear such clear visible signs so soon in the brain images.

I also wonder if even just the close physical contact itself has a positive impact on brain chemistry.

Yes, I think it does. But in my understanding that has been controlled in the research as well. Also, there is also a short-term downside to the physical contact. For me it took years of training to become less anxious about the proximity of another person. You are minutes at a time in hugging position with a person who can be a total stranger.

I'm a professional dancer and music and freestyle are the most demanding aspects of dance by far.

That said I'm also skeptical. Music and dance are being compared to "bicycle ergometers" and "training with equipment such as barbells and rubber bands". I'm pretty sure only one of these groups was having any fun. Unless the dance group were forced to social dance bachata in which case the misery probably evens out.

You might be surprised at how many people enjoy the feeling of grinding out improvement in the gym. In my experience it can be a lot more fun than dancing for certain personality types (mine included)

And for the exercise only group: > We avoided combined arm and leg movements in order to keep coordinative demands low

I'm skeptical too. You have one group that is doing something that takes full body coordination, with lots of different inputs and improvisation, versus something they attempted to minimize those aspects of. Not to mention the social parts of dancing with others.

But also hey, social dancing bachata is fun! If you're ever in NYC a good friend of mine teaches it at Pearl dance studio.

There are various complicated social dynamics related to couples dancing that might make it less than fun for some people. You need to spend several minutes in to close proximity with a stranger, and even be able to move at the same time. It took me years to get over this. Depending on the method dance partners are selected, you might experience rejection etc.

I lack the in-depth knowledge but correcting p-value thresholds for multiple hypotheses is very basic science. I doubt your criticism is valid given that some basic error like this would never pass peer review.

Correcting for p-values in brain imaging research is kinda elaborate, since you are essentially performing a t-test separately for each brain voxel. A brain image like the authors' will have about a million voxels (0.7 x 0.7 x 0.7 mm voxels). For multiple hypothesis correction, correcting for 1 million tests would be overly strict because neighboring voxels are highly correlated with one another, and it's unlikely for brain effects to really be confined to such a small area. Hence, researchers usually define a primary threshold for voxels (here p < .001 uncorrected), and then look for patches of many p < .001 voxels together. Here, the authors stated that they looked for patches of at least 50 contiguous voxels. The authors are just using some loose old-timey heuristic without justification or citation. These have been getting phased out mostly in the past decade. These types of heuristics don't actually test to establish that these thresholds won't yield tons of false positives (one of the best ways to do this is to basically randomly shuffle your data and see what are the actual cluster sizes generated by chance).

> some basic error like this would never pass peer review

It indeed shouldn't pass peer review! Yet, here we are. I think standards have gotten better since the paper's publication (2018), but there are no doubt there are still many reviewers who don't have a good intuition about what a significant cluster size should be. Off the top of my head, I can't give an exact number on the cluster size needed, but I'd be willing to bet a ton that what the authors used is not enough.

I think all the things that dance brings to the table over the mean "exercise" are clear first-principles wins (using your whole body, listening and dancing in rhythm, listening to music, letting yourself go / being silly)