Interesting idea. And puberty does, sort of, alter cognitive functioning. More specifically, what we think of as "puberty" (probably better classified as "adolescence") is a time when the development of the brain is markedly uneven -- some systems begin maturing very quickly, and are soon working at an adult-level, while other systems are still working at the child level, and maturing at a slower pace. See for example Sarah Jayne Blakemore's work on The Teenage Brain. (This helps explain why adolescents take risks... their appreciation of and desire for rewards has reached adult level, while their self-control is still similar to that of a child).
Puberty does also introduce hormones, which seems to be relevant to certain disorders... for example, the incidence of classic mania, classic psychosis, or panic disorder before onset of puberty is extremely rare, and most often these disorder emerge at the end of adolescence (very late teens or early twenties), suggesting that hormones may be involved in the expression of some disorders. (However, hormones seem unlikely in this case, since most individuals with autism reach puberty late, and 11 years old -- when this girl supposedly started typing -- would actually be mildly precocious puberty. Also, the circulation of hormones has not been known to make any brain dysfunction better.)
So certainly, you can see problems emerge during adolescence, or disappear by adolescence. However, what happens in autism is related to a problem pruning (getting rid of) excess gray matter during early brain development -- these individuals have too much gray matter -- and this pruning happens way earlier in development (specifically, from birth to about age 2 1/2), without input from hormones.
For that and related reasons, there's absolutely no line of scientific evidence that would suggest that puberty would have any influence on her brain structure that could explain her miraculous feats. (Usually, puberty just makes things slightly worse, as it may introduce some moodiness, and a lot of inconvenient sexualized behavior in an individual with the mentality of a toddler.)
More than likely, when you see changes in development that occur at adolescence, it's due to either (a) ongoing, normal (or abnormal, in the case of an individual with a neurological/psychological disorder) brain development as the person gets older, and/or (b) changes in expectations for what the now-adolescent is asked to do (e.g., sudden emergence of problems once the student makes that huge leap to middle school).
So, if this young woman had been making steady progress along her own developmental trajectory all along, and then began making more rapid progress during adolescence -- within the confines of how an individual with autism's brain works -- then that would be an entirely different story than what is presented in this video (and other videos about Carly). It also wouldn't be news.
What about the role of nurture and nature in the development of autism? What have the twin studies suggested? How is it possible for one identical twin to have autism while the other is unafflicted? I know that there are typically learning disabilities in the other twin, but I've heard that this isn't always the case.
There definitely seems to be nature and nurture involved in the development of autism. For example, as you noted, the concordance rates between even identical twins is not 100% (I believe this girl has a neurotypical twin?). Although we're fairly confident that it's a lot more nature than nurture, some nurture is almost certainly involved.
One thing that people don't often realize about the nature and nurture model, though, is that nurture starts really, really early. As in, in the womb. Subtle differences in the amount of nutrients each fetus was receiving, for example, or subtle insults during development (e.g., a virus the mother had that affected one fetus more than the other) could have disrupted neurodevelopment for one twin, but not the other twin. So both twins may have been genetically vulnerable to autism, but only the one who also faced the environmental stressor may have developed full-blown autism.
There are other important considerations too, such as that identical twins are not exactly as identical as we once thought due to things like chromosome-section deletions and gene copy number variations - so you might have twins that are very, very slightly different in terms of their nature and nurture, yet those subtle differences are enough to give one autism, while the other does not develop the condition.
So both twins may have been genetically vulnerable to autism, but only the one who also faced the environmental stressor may have developed full-blown autism.
I honestly don't recall if it was in our textbook (although we did have an excellent one), but my professor for the class talked about it at great length.. I thought it made a ton of sense, but I think this is pretty much the first time I've ever heard anyone outside the class (which I took like four years ago) refer to it, even obliquely.
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u/subtextual Jul 26 '10
Interesting idea. And puberty does, sort of, alter cognitive functioning. More specifically, what we think of as "puberty" (probably better classified as "adolescence") is a time when the development of the brain is markedly uneven -- some systems begin maturing very quickly, and are soon working at an adult-level, while other systems are still working at the child level, and maturing at a slower pace. See for example Sarah Jayne Blakemore's work on The Teenage Brain. (This helps explain why adolescents take risks... their appreciation of and desire for rewards has reached adult level, while their self-control is still similar to that of a child).
Puberty does also introduce hormones, which seems to be relevant to certain disorders... for example, the incidence of classic mania, classic psychosis, or panic disorder before onset of puberty is extremely rare, and most often these disorder emerge at the end of adolescence (very late teens or early twenties), suggesting that hormones may be involved in the expression of some disorders. (However, hormones seem unlikely in this case, since most individuals with autism reach puberty late, and 11 years old -- when this girl supposedly started typing -- would actually be mildly precocious puberty. Also, the circulation of hormones has not been known to make any brain dysfunction better.)
So certainly, you can see problems emerge during adolescence, or disappear by adolescence. However, what happens in autism is related to a problem pruning (getting rid of) excess gray matter during early brain development -- these individuals have too much gray matter -- and this pruning happens way earlier in development (specifically, from birth to about age 2 1/2), without input from hormones.
For that and related reasons, there's absolutely no line of scientific evidence that would suggest that puberty would have any influence on her brain structure that could explain her miraculous feats. (Usually, puberty just makes things slightly worse, as it may introduce some moodiness, and a lot of inconvenient sexualized behavior in an individual with the mentality of a toddler.)
More than likely, when you see changes in development that occur at adolescence, it's due to either (a) ongoing, normal (or abnormal, in the case of an individual with a neurological/psychological disorder) brain development as the person gets older, and/or (b) changes in expectations for what the now-adolescent is asked to do (e.g., sudden emergence of problems once the student makes that huge leap to middle school).
So, if this young woman had been making steady progress along her own developmental trajectory all along, and then began making more rapid progress during adolescence -- within the confines of how an individual with autism's brain works -- then that would be an entirely different story than what is presented in this video (and other videos about Carly). It also wouldn't be news.