Objects that have sharp edges generate higher frequency harmonics when agitated, because lower-size features resonate on higher frequencies (like shorter strings ring on higher pitch). Objects that are round resonate on low frequencies only. The "kiki" sound has more high frequency content than the "bouba" sound, and it's no mystery why the brain associates one with the other.
That's one theory. Another one I can think of is that sharp edges are scary, and most distress calls are high pitched.
Also, the thing about high frequencies and sharp edges lead to a contradiction: babies are more round than adults and produce higher pitched sounds, this is almost universal across all species.
There are other tentative explanations, such as how the vocal tract acts when producing these sounds, with "bouba" sounds being the result of smoother movement more reminiscent of a round shape.
"kiki" is not just higher pitched, it is also "shaped" differently if you look at the sound envelope, with, as expected, sharper transitions.
So to me, the mystery is still there. Is is the kind of thing that sounds obvious, in the same way that kiki sounds obviously sharper than bouba, but is not.
> The "kiki" sound has more high frequency content than the "bouba" sound
And where did you get that from?
In non-tonal languages the pitch conveys almost no information and people speak at very different ones (and for instance a male saying "kiki" will say it at lower frequencies than a woman saying "bouba" most of the time) so I find your affirmation very dubious.
> and it's no mystery why the brain associates one with the other.
Specialists of the field find that mysterious but some smartass on HN disagrees.
For each chick they do 24 trials divided into 4 blocks with retraining on the ambiguous shape and actual rewards after each block. During the actual tests they didn't give rewards. In figure 1 they show the data bucketed by trial index. It's a bit surprising it doesn't show any apparent effect vs trial number, e.g. the first trial after retraining being slightly different.
I have to admit I'm super skeptical there's not some stupid mistake here. Definitely thought provoking. But I wish they'd kept iteratively removing elements until the correlation stopped happening, so they could nail down causation more precisely.
I do agree my skepticism level rises extremely high in any experimental psychology experiment. There’s just so many ways to bias results, in addition to “do enough experiments and one of them will get a statistically unlikely result” problem.
This group does a lot like this https://www.dpg.unipd.it/en/compcog/publications … so that’s tempting to think they keep trying things until something odd happens (kind of like physicists who look for 5th forces… eventually they find something odd but often it’s just an experimental issue they need to understand further).
This is just one micro-instance of a much larger thing. Brain encodes structural similarity across modalities. Corollary: language is far from arbitrary labels for things.
No, language is still pretty close to arbitrary labels. The handful of tenuous common threads like the bouba-kiki effect don't change the overall picture that much. The simple fact that language varies as much as it does is sufficient to prove that it's only loosely bound to anything universal.
I think this is a misunderstanding of the arbitrariness of the sign. Arbitrary doesn't mean "random" or "uniformly sampled." The fact there are systematic tendencies among languages in how things are called doesn't negate the arbitrariness of the sign, they could have been called other things. We can also decide to refer to things by another name and we can use any arbitrary name we like! There is no limits on what names we can use (besides silly physiological constraints like having a word with 50 000 consonants). But, of course, there's much more to language than just labels!
For me, the interesting thing in this paper vis-à-vis language is that it shows how much innate structure in cognition must shape our language.
I'm not entirely sold by this discovery. For example when you learn to train dogs, you learn about the 3 voices. Encouraging voice, atta boy, negative voice, more stern, and the big "NO!".
To some degree these words type sounding language are doing the same thing. Some sounds will irk, some will soothe, and it would affect this 'evidence' found.
I think the researchers agree with your premise. The “evidence” is not that chicks have more language understanding than previously understood, but rather that the source of the universality of bouba/kiki is due to something more primitive than built in human language hardware.
> But I guess it's about why so we associate those with spiky shapes, though surely it's because they represent sharp immediate changes in frequency?
Sure, but it's a very abstract connection between objects being sharp in vision and frequencies changing sharply in hearing. There's no guarantee any given organism would make the connection.
>But I guess it's about why so we associate those with spiky shapes
I think the why just got a lot tricker than we imagined. Because we failed to replicate this experiment on other primates, we couldn't avoid a semantic suspicion about those associations. Now we probably have to set semantics aside or let it get a lot weirder, because we can replicate across ~300My.
>surely it's because they represent sharp immediate changes in frequency?
Maybe, and I think "multi-sensory signal processing" is the best framing, but the representation could also carry harder to think about things like "harm".
It's also super cool because the bouba-kiki effect framing was chosen due to methodological convenience for linguists and cultural anthropologists and their experimental bounds, not neuroscientists or signal processing folks. We could potentially find other experiments quickly, since chicks are a model organism and the mechanism is clear.
I think it’s natural to think of this in terms of frequencies so the kiki shape has a higher visual frequency. As does the word have a higher audio frequencies within in than bouba so that is naturally associated with the lower frequency undulating line of that shape.
I see several people say primates don't show the effect, however all tests on primates were done with a "language-competent bonobo" and "touchscreen trained chimpanzees (N=6) and gorillas (N=2)" that are first trained to do various language/picture association tasks and then tested like how you'd test humans. It would be interesting to test primates using the same methodology they used here on chickens. The previous language/computer training in the monkeys might have interfered with a more low-level/intuitive bouba-kiki effect.
Very likely this experiment suffered from a lack of thorough double blind control. Researcher bias may have generated subtle subconscious queues to the chicks on which shape to pick unrelated to the sounds.
bad_username|7 days ago
GuB-42|7 days ago
Also, the thing about high frequencies and sharp edges lead to a contradiction: babies are more round than adults and produce higher pitched sounds, this is almost universal across all species.
There are other tentative explanations, such as how the vocal tract acts when producing these sounds, with "bouba" sounds being the result of smoother movement more reminiscent of a round shape.
"kiki" is not just higher pitched, it is also "shaped" differently if you look at the sound envelope, with, as expected, sharper transitions.
So to me, the mystery is still there. Is is the kind of thing that sounds obvious, in the same way that kiki sounds obviously sharper than bouba, but is not.
IsTom|7 days ago
littlestymaar|7 days ago
And where did you get that from? In non-tonal languages the pitch conveys almost no information and people speak at very different ones (and for instance a male saying "kiki" will say it at lower frequencies than a woman saying "bouba" most of the time) so I find your affirmation very dubious.
> and it's no mystery why the brain associates one with the other.
Specialists of the field find that mysterious but some smartass on HN disagrees.
aaptel|7 days ago
unknown|7 days ago
[deleted]
mnbs|7 days ago
PaulDavisThe1st|7 days ago
Strilanc|7 days ago
I have to admit I'm super skeptical there's not some stupid mistake here. Definitely thought provoking. But I wish they'd kept iteratively removing elements until the correlation stopped happening, so they could nail down causation more precisely.
rubidium|7 days ago
This group does a lot like this https://www.dpg.unipd.it/en/compcog/publications … so that’s tempting to think they keep trying things until something odd happens (kind of like physicists who look for 5th forces… eventually they find something odd but often it’s just an experimental issue they need to understand further).
verteu|8 days ago
a115ltd|8 days ago
andrewflnr|8 days ago
suddenlybananas|8 days ago
I think this is a misunderstanding of the arbitrariness of the sign. Arbitrary doesn't mean "random" or "uniformly sampled." The fact there are systematic tendencies among languages in how things are called doesn't negate the arbitrariness of the sign, they could have been called other things. We can also decide to refer to things by another name and we can use any arbitrary name we like! There is no limits on what names we can use (besides silly physiological constraints like having a word with 50 000 consonants). But, of course, there's much more to language than just labels!
For me, the interesting thing in this paper vis-à-vis language is that it shows how much innate structure in cognition must shape our language.
downboots|8 days ago
keyle|8 days ago
To some degree these words type sounding language are doing the same thing. Some sounds will irk, some will soothe, and it would affect this 'evidence' found.
spagettnet|7 days ago
alienbaby|8 days ago
But I guess it's about why so we associate those with spiky shapes, though surely it's because they represent sharp immediate changes in frequency?
I'd be interested on results of shapes imagined when you take the source as musical or other non speech sounds.
canjobear|8 days ago
Sure, but it's a very abstract connection between objects being sharp in vision and frequencies changing sharply in hearing. There's no guarantee any given organism would make the connection.
selridge|8 days ago
I think the why just got a lot tricker than we imagined. Because we failed to replicate this experiment on other primates, we couldn't avoid a semantic suspicion about those associations. Now we probably have to set semantics aside or let it get a lot weirder, because we can replicate across ~300My.
>surely it's because they represent sharp immediate changes in frequency?
Maybe, and I think "multi-sensory signal processing" is the best framing, but the representation could also carry harder to think about things like "harm".
It's also super cool because the bouba-kiki effect framing was chosen due to methodological convenience for linguists and cultural anthropologists and their experimental bounds, not neuroscientists or signal processing folks. We could potentially find other experiments quickly, since chicks are a model organism and the mechanism is clear.
Things could move fast here.
jaffa2|8 days ago
downboots|7 days ago
bondarchuk|5 days ago
References here https://evolang.org/jcole2022/proceedings/papers/JCoLE2022_p...
crazydoggers|7 days ago
patcon|7 days ago
It must take some strange things to survive co-evolution with humans for several thousands years
unknown|8 days ago
[deleted]
tetris11|8 days ago
shermantanktop|8 days ago
Recursing|8 days ago
> We tested a total of 42 subjects, 17 of which were females.
K0balt|7 days ago
saalweachter|7 days ago
gnarlouse|8 days ago
the__alchemist|7 days ago
thesmtsolver2|8 days ago
AreShoesFeet000|8 days ago
boppo1|8 days ago
mastercheif|8 days ago