Autism and 2d/4d Finger Ratio

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Most autistics are male. Most males show that ratio. Your results will be skewed.

My index finger is longer than my ring finger - closer in length to my middle finger, even.

And further:

10 - 13 is too few to say anything about NTs, but 22 - 1 or 62 - 10 is fine for AS? They didn't even list the sexes separately.

There are tons of resources, if you google "2d/4d ratio". I have seen no disagreement that the lower 2d/4d ratio is reflective of high levels of testosterone during fetal development. All the research I have seen shows a correlation between low 2d/4d ratios and severity of autism. This, in itself, obviously does not mean that it causes autism, because many non-autistic males and some non-autistic females have lower than normal ratios. Normal ratio for men is considered .98 and for women it is 1.0 or higher.

There is not a consensus, though, on other aspects like, whether or not is an indicator of sexual orientation.

I know that maternal stress is a big contributing factor to the increase of testosterone in the womb. I haven't researched it, but I'm guessing that American pregnant women are under more stress today than they were 40 or 50 years ago. I wonder if this could be a contributing factor to the rise in autism in developed countries.

I have seen research (Discover Magazine) that suggests that prehistoric hunters and gathers were more masculinized with larger brains; and domesticated, less masculinized humans were an adaptation to agricultural society. I also remember reading in the magazine that there is evidence that this trend is now reversing. Could this be an adaptation to the Information Technology Age?

I think most people would agree that life is becoming more competitive and stressful in our society. I think that most people would also agree that robust individuals have an easier time accomodating the physcial effects of stress than fragile individuals. Combat studies with PTSD suggest this.

I have seen posts that suggest that autism is the next step in evolution. I think it might be more reasonable to suggest that masculinized, humans, in general, would be a natural adaptation to a more competitive, stressful environment. I think it is possible that the relationship between stress, testosterone in the womb, and masculinized offspring could be an adaptation to our environment. And, since stress, in itself can trigger it, it wouldn't require the process of thousands of years of evolution for a significant adaptation like this to occur.

Just a thought.

When my son was diagnosed with Asperger's, the doctor looked at both of our finger lengths and made a note of them.

He said it was part of a study. I think it has to do with Baron-Cohen's extreme male brain theory and he considers it a

genetic marker. It shows up more frequently in female Aspies and lesbians.For the record, I am female and my index

finger is visibly shorter than my ring finger. I always assumed every one had fingers of different lengths but looking

around I see it isn't so. For some reason my middle finger is particularly long.

ahogday, there is no rise in autism, and evolution does not produce visible results in one generation.

Source?

http://www.autismresearchcentre.com/doc ... g_etal.pdf

Simon Baron-Cohen does speaks to this in his book "The Essential Difference: Male And Female Brains And The Truth About Autism". It was one of the first books I read when my son was diagnosed and I was identified as AS.
It definitely holds true for the Aspies in our family that the ring finger on the right hand is significantly longer than the index finger. Since reading of this, I have noted that other female Aspies I have come across also have the longer ring finger in relation to index finger on the right hand. It will be interesting to see how all the research etc comes together in the future.

I agree with your source that there has not been a consistent increase in the reported cases of Autism on a year to year basis. But, overall since 1990, for whatever the reason, the number of Autism cases reported has increased. And, per excerpt, below from the study you provided, the study is questioning the overall rise but does not provide conclusive evidence that there has not been a rise.


There strong beliefs on both sides of the issue," Newschaffer says. "But if you try to get objective and sit back -- if you try to be honest -- I don't think the data are valid, precise, or good enough to tease these things out."

A new CDC study is trying to unravel the issue. But Newschaffer thinks this isn't likely to provide definitive answers.

"We are not likely to develop a conclusive body of evidence to either fully support or fully refute the notion that there has been some real increase in autism risk over the past two decades," he writes.


Regarding evolution, I'm not suggesting an evolutionary change, in the classic sense, just the thought of the possibility of a generational adaptation to the environment. A multitude of external and internal stressors that we are exposed to can change the physical traits of our children. An example would be the mutations caused to children of the Parents that were exposed to the Nuclear bombs in World War 2. In the case of Autism and In Vitro Increases increases in testosterone, I don't think we are seeing anything new, just a possible increase of traits in humans due to environmental stressors.

OK. So maybe not junk science.

I've heard of a similar study done for gay people.

It's an interesting correlation, but at the end of day it's entirely useless information. I also maintain that it's junk science. Until further notice.

Does hand dominance make any difference.? my idex is shorter on my left than my right.

Only 10 girls and lumped together with the boys, so you can't really see if sex matters.

Considering how recent the autism disorders are, it makes much more sense that increasing awareness is the cause of that, rather than a lot of people suddenly getting the disability. Witness the amount of adults going "finally I have an explanation for my lifelong weirdness & problems". Of course, it can't be ruled out, but if it is increasing no one has found a cause or proof of that.

Fair enough.

It becomes junk science when you extend correlation into causality without supportive evidence. I didn't see that in the links posted.

But if I see spam for finger lengthening exercises to cure autism, I'll have a different opinion of that "science".

It becomes junk science when it purports to be of any significance based on sketchy evidence.

I haven't had the time to read the article yet, so until further notice.

[I have asperger's and my index and ring fingers are the same length, even though i'm biologically male. I also had gender dysphoria at one time (i'm not transsexual, though). I think the idea that autism is an "extreme male brain" is bunk, it is a reductionistic fallacy . I've met several transpeople that have Asperger's and yet do not identify as male.

The studies indicate a lower correlation for low 2d/4d ratios among people diagnosed with Aspergers. If you limit the study for the results for people that have Aspergers, the correlation is much more in line with the general population; I think the poll and many of the comments in this discussion are reflective of that. The more compelling correlation is with the people lower on the Autism Spectrum.

There is research that indicates that there is a correlation between the "extreme male brain" and homosexuality and also research that indicates a high finger ratio, is an indicator of homosexuality. I think, if anything, this shows that general masculine and feminine characteristics do not dictate sexuality.

I recently read an article that suggested that IQ in the Aspergers population is close to that of the general population and is skewed a little higher because the higher functioning asperger people are more likely to get diagnosed. The author also suggested that high IQ is in the minority of the Asperger population, just as it is in the general population.

The author's opinion is the Asperger advantage is in conscientiousness and associative horizon (the ability to think outside of the herd). He did not deny that Aspergers was not associated with genius, and in fact was challenged to name someone noted as a genius in history that did not have the asperger advantage.

Link to the Article:
http://www.paulcooijmans.com/asperger/straight_talk_about_asperger.html

I think our discussion and most of the other discussions I have seen on the "Wrong Planet" are reflective of this "Asperger Advantage", and why so many new correlations are presented with new ideas.

I try to present my ideas with words like I think, opinion, suggest, possible, reflect, shows, etc., I have an aversion to saying I have the causation or this is wrong, because it is likely that someone will have another correlation that may take me closer to what I am curious about.