Autism's Four Core Subtypes

(thetransmitter.org)

90 points | by domofutu 8 hours ago ago

51 comments

  • geor9e 5 hours ago

    Reminds me a bit of the MBTI personality test, where they make up 4 types of question to arbitrarily split the population, so 2x2x2x2 = 16 subtypes. It's true by it's own definition. Which is fine, but are these particular arbitrary boundaries useful? Perhaps. Could the splitting lines have been just as useful in different arbitrary place. Perhaps. A lot of people who take the MBTI find they're on the boundaries flip-flopping into a few different pigeonholes depending on different times they take the test. So it's important to let people know they can be in multiple buckets (are a bit in all of them), and take a little advice from each community.

    For this one they split autism into 3 groups (core,social,developmental) then split core into (mild,severe), to make 4 total.

    • Y_Y 4 hours ago

      > Troyanskaya and her colleagues investigated the variants associated with a person’s collection of characteristics. They applied a statistical model to data on the traits and behaviors of 5,392 autistic people from the SPARK research cohort. By adjusting the number of groups, the team found the most significant similarities among participants when the model sorted the cohort into four autism subtypes.

      https://www.medrxiv.org/content/10.1101/2024.08.15.24312078v...

      Not my field, but the statiscal analysis seems legit.

      • pfisherman 3 hours ago

        Have not read the article in depth yet, but I am very familiar with the Troyanskaya lab. They are good and their articles are always worth a read.

        They are using a geodesic finite mixture model, which I am not familiar with, but seems to be an extension of mixture models to non Euclidean metric?

        Pleiotropy can be tricky though, as traits / diagnoses / observations can have causal relationships amongst themselves. For example, a variant that impacts obesity may be statistically associated with heart attacks; but the relationship between the variant and heart attacks is not directly causal in the sense of something like a variant that alters function of an ion channel expressed in cardiac smooth muscle.

    • kelseyfrog 4 hours ago

      Reminding is different than being the same.

      For example, Big5/OCEAN/FiveFactor model uses factor analysis which has statistical reasoning behind the number of factors. In fact, the semantic meaning of the factors comes up after the analysis, not before. It's the same as clustering or GMM, the semantic meaning of the clusters is applied after the partitioning.

      The concept of partitioning people is the same, however, the order by which meaning is applied is opposite which makes them completely different in practice.

    • pfannkuchen 3 hours ago

      If the data is a roughly uniform distribution across the dimension space, then yes absolutely.

      If, however, there is significant clustering within the dimension space, and those clusters are taken as groups, then it seems valid.

      I would tend to be generous to the researchers and assume a mostly discrete clustering until I see otherwise. To apply grouping like this without discrete clusters would be unprofessionally naive on their part.

    • h0l0cube 5 hours ago

      They also posit correlations with epigenetic differences. If there’s distinct biological mechanisms at play, this gives some credence to splitting autism into separate conditions

    • w23b07d28 5 hours ago

      It's not true by its own definition, it's just that if you soak it in, you will actually start to see the patterns behind it among people. It's still going to be pseudoscience because there are a lot of variables, but it often works and even more often people don't know what to look at or what to put together, because you'll find really A LOT of articles on the Internet that try to run mechanics on certain types without understanding what or why. I assume that if you want to put this together more precisely, there is a lot of scope here.

      And lest it be said that I'm talking out of turn myself, I only became interested in this whole MBTI thing because an ENFP once told me I was an INTP after a few hours of talking about silly things. That's exactly what these tests once told me. Of course, these are still anecdotes, but we are sciency.

      Is it a problem that someone has catalogued autism in this way? Is it a question of lack of precision or bad direction? Am I asking the wrong questions?

    • colechristensen 3 hours ago

      There’s a better way to frame this issue: being able to consistently label a characteristic is only useful if it can help in identifying the underlying mechanism or is helpful in choosing an effective treatment.

      A whole lot of mental health knowledge fits into the category of repeatably identifiable categories of dubious usefulness.

      Think phrenology: it is indeed possible to categorize the shape of people’s head in a statistically valid way… it just has nothing to do with their mental health.

      • LeonB an hour ago

        Are you a libra? This sounds like something a libra might would say! /s

        “Repeatable identifiable categories of dubious usefulness”

        Yep, there’s a lot of this in modern science.

        “Is this method of classification useful? wrong question! All you need to ask is, is it easy to write a reproducible paper (or shareable web content) on this method of classification? Yes, yes it is!”

        There’s a lamppost problem at work here.

        • colechristensen 35 minutes ago

          Eh, it's more like the DSM was written primarily with the concept of billing and charting in mind. If you track and bill medical conditions, you need a consistent language for things that will be consistent across medical providers.

          It solves a problem, just not the problem most people think it solves.

          https://en.wikipedia.org/wiki/DSM-5

  • greesil 6 hours ago

    As someone with a close family member who is autistic, I am always bothered by the phrase "if you have met one person with autism, you have met one person with autism". Autism as a diagnostic classification is so broad that the non verbal are lumped in with those with rigidity behavior, when at least to me they seem like they should just have a different diagnosis. This is not just playing semantics if they're able to correlate against specific sets of genes. This work seems highly relevant, IMO

    • jtsiskin 6 hours ago

      The expression you quoted is completely agreeing with you! It’s a play on the expected idiomatic ending “then you have met everyone with autism”, pointing out that the diagnosis is broad and everyone is different

      • greesil 6 hours ago

        Why even have the word autism? It's almost meaningless.

        • furyofantares 3 hours ago

          A characteristic autistic trait is having a narrow and deep tunnel of attention.

          Perhaps so narrow and deep that you're unable to learn language, because it requires a more holistic processing, and less focus on individual components.

          Perhaps so narrow and deep that you're overwhelmed by sensation, processing every touch, sound, sight stimulus individually, leaving little energy to put everything together.

          Or perhaps only so narrow and deep that you are extremely focused on math. Or collecting insects. Or memorizing train routes.

          I don't know if this is an explanation. But it is extremely plausible for a wide variety of outcomes to be usefully categorized by a singular trait.

        • cogman10 5 hours ago

          The symptoms cluster together and are related. Someone with sensory issues is also likely to have food aversions, for example.

          It's also useful for diagnostics and treatment. It means you don't have to fight insurance as much or need rediagnostics to get needed therapies. I don't need to get my child with food aversions, speech delay, and sensory issues a new diagnosis for each just because some people with autism don't have those issues.

          • mindslight 4 hours ago

            That sounds like a problem with the medical gatekeeping industry rather than anything fundamental. Like a blanket diagnosis of "human" would get you the same thing, but for the middlemen realizing that would completely destroy one of the levers they use to defraud.

            • lox 3 hours ago

              With a prevalence rate of < 2% (at least in Australia) this seems like an incredibly mathematically flawed take. Whilst a broad/blanket diagnosis isn't useful for making generalisations about individuals in that group, it's certainly societally useful.

            • idiotsecant 4 hours ago

              So it solves a problem, then? Its useful? Saying a problem would not be a problem if the universe was a little better is not particularly useful.

        • Frummy 4 hours ago

          Each seed may land in a unique place, being swept by the wind from the same tree.

        • Muromec 3 hours ago

          So the normies have a way to explain weirdness and go on with their day.

        • throwawaymaths 4 hours ago

          Because autism got a shit ton of research funding from scared parents a decade ago

        • Spivak 6 hours ago

          "hot" is still a meaningful word even though 100 F°, 1000 F°, and 1,000,000 F° aren't comparable at all. They're nonetheless still all experiencing heat.

          • blargey 5 hours ago

            Yes, if we could pin it to a linear scale of Degrees Autistic (Farenheit), that could be estimated with reasonable precision for all day-to-day relevant values by feeling the nearby air on your skin, nobody would complain about "Austism" being too broad.

            • o11c 4 hours ago

              Usually it's at least 4 scales with no strong correlation (and a couple more that are correlated more). They do have them.

              Thus, it is incorrect to refer to Autism as a "spectrum". Instead, we should correctly call it a "manifold".

            • Spivak 5 hours ago

              Am I missing something you can though. That's actually kinda how it is. I detest the phrase "high functioning" but that group is roughly your outside temperatures. You'll notice the difference between 30° and 80° and the same temperature 72° can feel different in the summer, winter, before it rains, when it's humid/dry but is still the same intensity. Then there's 1000° degrees where (and this is someone I know) he stripped naked, ran through downtown, and yelled at random restaurant workers calling them fascists for not lettting him in and then got into a fight with the cops.

              I think broadly that's what the "spectrum" characterization is meant to convey. And you should expect this, in code there's one happy path and a million different ways to err, some more catastrophic than others.

          • bbarnett 5 hours ago

            It seems to me that something could be hot enough, that you could vaporize before your nerves signal your brain.

    • saghm 6 hours ago

      > Autism as a diagnostic classification is so broad that the non verbal are lumped in with those with rigidity behavior, when at least to me they seem like they should just have a different diagnosis.

      As someone with a diagnosis, I've gotten into the habit of referring to myself as "on the spectrum" when discussing with people rather than using a specific term. It helps emphasize the fact that there's a range of potential manifestations, and (hopefully) helps remind people that their expectations based on past experience might not fit my behavior exactly.

    • Jensson 6 hours ago

      Merging autism with asperger went the exact opposite direction of where it needed to.

      • NeuroCoder 5 hours ago

        The problem was that a diagnosis of Asperger's was unreliable and therefore useless. We definitely need to identify individuals within the diagnosis of autism spectrum disorder that can reliably be identified and benefit from specific interventions. However, Asperger's did not provide that.

        • TeaBrain 36 minutes ago

          I'd argue that having the descriptor of "asperger's" is much more useful than simply having a blanket descriptor of "autism". Low functioning people who are described as having autism, have very little in common with most of the high functioning type.

        • throwawaymaths 4 hours ago

          The problem was that asperger was a problematic physician at best.

      • SpicyLemonZest 6 hours ago

        The reasons why the change was made (https://www.thetransmitter.org/spectrum/why-fold-asperger-sy...) still make sense to me. The autism spectrum is quite wide, and I'd 100% believe something meaningful coming from the source study, but the specific category of Asperger's was based on factors that don't seem to matter much and weren't being reliably evaluated.

  • tomrod an hour ago

    Hierarchical clustering applied to brain scans. As a clustering output, it's useful to conceptualize but not definitive of what one can expect from behavior nor development. If I am not mistaken, this is the original paper.[0]

    [0] https://www.nature.com/articles/s41593-023-01259-x

  • skissane 2 hours ago

    I’m sceptical of research based on a single diagnostic label - such research assumes that the boundary between that specific diagnosis, other diagnoses, and no diagnosis, is valid - while (at least some) research which tests that assumption rather than making it, by including cohorts with other diagnoses and also no diagnosis, ends up challenging that assumption - e.g. https://www.nature.com/articles/s41398-019-0631-2 - but if the challenge is correct, how much validity is there in research which relies on it?

  • NeuroCoder 4 hours ago

    It's important to note that models that use genome wide association analysis have demonstrated extremely high predictive value across large cohorts sharing geography but are very poor when applied on a geographically distinct population. This suggests that although autism has a strong association with genetics, neurophysiology unique to autism develops in the context of highly complex genetic associations that are likely subject genetic drift across population and time.

    When we have a a few genes of interest that are important in screening for a rare disease we accept that novel variants will continue to be identified throughout the years as more people are screened. Autism as a prevalence of 1-3%. I don't remember the exact number but I think something like 30% of autism diagnoses are believed to be secondary to fairly severe but distinct genetic syndromes. So when we talk about a subgroup of autism without clear etiology we are looking at a fraction of 70% of 3% of the population. We're approaching rare disease territory when we talk about subgroups within autism. A rare disease with a highly complex genetic association across the genome that is subject to genetic drift is not a good candidate for genetic screening.

    All that being said, studies like this may provide valuable insight into what microbiology is being influenced, even if we can't reliably predict which variants are responsible. Id love to see future investigations relate genetics to biomarkers instead of behavioral tests in autism.

    • ruthmarx 40 minutes ago

      > This suggests that although autism has a strong association with genetics, neurophysiology unique to autism develops in the context of highly complex genetic associations that are likely subject genetic drift across population and time.

      Wouldn't it be more likely local culture and brain plasticity are the cause of these differences?

  • 93po 6 hours ago

    sort of off topic, but does anyone else have the experience of consistently having bad interactions in real life any time autism is discussed? like the reasons are so varied but it's so consistently not great. i feel like it's rooted in a "i know autism better than you and i feel threatened anytime something is expressed that differs from my own opinion/experience with it". and sometimes people are offended with any opinion or anecdote or experience expressed on it at all in a "don't mansplain autism to me" sort of way (i'm not a man, just to be clear, and obv mansplaining isnt unique to men).

    not saying this to be unkind or mean to anyone. it just feels like such a super touchy topic. i started completely not engaging in conversation around it at all and pretending like i don't know anything about it.

    • Fnoord 11 minutes ago

      My wife and I are on the spectrum hence we read up on it regularly. Especially when we were first diagnosed. Lately we read more on it given our kids are likely on the spectrum with our oldest being in a diagnosis trajectory.

      One major thing which annoys me is when autism is being used as a curse-word. Such as 'no autism please' when looking for people to play with in an online game. The irony being this is possibly (non-diagnosed) high functioning autistic who don't want to play with low(er) functioning autistic. One thing to do in such a case is join and prove them wrong (that you are good enough) and then leave saying 'btw I am on the spectrum'. But it generally isn't worth the hassle. If someone uses such language, they're likely toxic, so I just avoid them. Plus, there is the ignore list. This works reasonably well. Though I also use this to ignore people whom I find under-performing.

      But one thing which comes to mind is that even though I am on the spectrum it is simply untrue you are compatible with other people who are on the spectrum. For example, when I am under stress I make certain sounds (coping) which my wife finds super annoying. I also remember a guy being hardcore Christian and on the spectrum (he gets annoyed when I curse), while we are agnostic.

    • uncletaco 6 hours ago

      No. The greatest interaction I had was when a kid didn’t hold a door for me and his mom said “I’m sorry he has Asperger’s and it’s a little heavy on the ass.”

      Then we ended up in the same waiting room for a while and she talked about accommodating her son and how they managed it. What was really interesting is the kid looked like it was the first time he heard his mom talk to someone else about it and him and I could tell he was embarrassed but really loving her that moment.

      • cuttysnark 6 hours ago

        > it's a little heavy on the ass

        I hadn't heard this idiom before so I looked it up and I couldn't find anything relevant. What does this phrase mean in this context?

        • umanwizard 5 hours ago

          The first syllable of Asperger sounds like “ass”, and the mom was making a pun based on that fact (pointing out that her son’s Asperger’s made him an ass).

          • cuttysnark 5 hours ago

            Saying it out loud made it click. Thank you.

    • vampirical 3 hours ago

      You’re probably going to think I’m very presumptuous but I’m going to say this anyway in case it is helpful for you.

      If people are frequently offended when you speak on a topic you’re probably being offensive somehow through content or delivery.

      In my experience the thought “[they] feel threatened anytime something is expressed that differs from […]” is not accurate and it also turns off your brain on trying to figure out what is actually going on. I can recommend from personal experience a small apology and transition to more listening in that moment. If more feels appropriate, giving it some time and space and re-engaging gently to discover what went on for them in that moment can yield a lot of value for both sides.

    • ggm an hour ago

      It is certainly one of several topics which really demand some caution to raise, such as religion, abortion, women's reproductive rights and the sexuality/gender debate, not to mention trigger warnings, campus DEI politics and academic freedom.

      I am always abashed when I walk into this space and frequently resent it when I am led into it by others.

      I like to imagine during the late 18th and early 19th century it was equally hard to have dispassionate discussions about slavery. In the 1920s alcoholism, and feminism. Since many years in many cultures homosexuality and according to Pierre telhard de Chardin almost always since we have looked back in time incest. I think he argued for a genetic component but perhaps not in as many words.

      Consider the Rosenbergs, or David Irvine, or Sir Anthony Blunt, and how rancorous debate got. Or, F.R. Leavis and the academic career paths for professors of English at that time. I knew academics whose careers were ruined by being in the wrong department at the wrong time by that.

      Or eugenics which until the Nazi rise to power was a tolerably normalised debate. Personally, I am glad we cast that into a different tone of voice but in context it might be indicative of like cases in times past.

    • tapland 5 hours ago

      I see this but usually only when someone who has never saught a diagnosis or have any shared experiences keeps referring to their supposed autism in a community with a lot of autistic people who will backlash.

      Never seen a discussion go bad _about_ it.

    • 23B1 2 hours ago

      The hardest part for me is understanding the difference between legitimate diagnoses and people who use it as a sort of veneer for antisocial behavior.

  • kayo_20211030 6 hours ago

    I spend no time considering genetic variations, or genetic correlations, I deal with what's in front of me. This study is _almost_ backcasting; it might improve the model, but, not the outcome.

    Maybe the study is fine and valuable, and maybe it'll lead to something. Maybe? But, it does nothing in the present. Not in the here and now.

    • tapland 5 hours ago

      If we can find specific subtypes it would be extremely helpful. You can’t expect everything to be presented only with a complete solution.

      • elcritch 5 hours ago

        Exactly, lumping in all autism into the same overall category when there could be very different underlying biological mechanisms would potentially block progress.

        For example, a medication that could work wonders on one subtype by affecting a biological mechanism unique to that subtype could be found not to meet clinical standards because it didn't work on the other subtypes or even make them worse.

        In other words, it's a confounding variable which needs to be discovered and characterized after which it could play significant role in advancing treatments and understanding.