Oh, i forgot, i can also tell you why there is this increase in autism lately. though it is from another piece i did on whether or not watching TV causes autism. I will post it here anyways because it will tell you WHY we have this increase.
Bare with me.
Today, Cornell University researchers are reporting what appears to be a statistically significant relationship between autism rates and television watching by children under the age of 3. The researchers studied autism incidence in California, Oregon, Pennsylvania, and Washington state. They found that as cable television became common in California and Pennsylvania beginning around 1980, childhood autism rose more in the counties that had cable than in the counties that did not.
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While i have already covered the
Etiology of autism, the new claim that watching television can cause autism has been made.
While the etiology of autism is by no means complete or perfect, watching television is just not a proper cause for autism.
From a recent article in Slate the following is stated
Last month, I speculated in Slate that the mounting incidence of childhood autism may be related to increased television viewing among the very young. The autism rise began around 1980, about the same time cable television and VCRs became common, allowing children to watch television aimed at them any time. Since the brain is organizing during the first years of life and since human beings evolved responding to three-dimensional stimuli, I wondered if exposing toddlers to lots of colorful two-dimensional stimulation could be harmful to brain development. This was sheer speculation, since I knew of no researchers pursuing the question.
While sheer speculation in and off itself might be a virtue, especially if it is followed up, having speculations and reporting on it, without properly investigating the material, is always a bad idea.
This article has quite many errors and mistakes in it.
One error, that i see many places, is that there is a either just a rise in autism, or an epidemic. This argument is a mistake which has a few sources.
The first cause of this mistake is that in the 1980s the definition of autism was changed. This means that a lot of people that were previously living without a diagnosis now got diagnosed with autism. Which naturally resulted in an increase in people diagnosed with autism.
Another, similar, argument is that it is caused by "something or other" which is the reason we haven't seen it untill the 20th century. In history there are very few cases of autism from before the 20th century, and this has caused many people to assume it is something new. And since it is new it must have a cause coming from changes in our society or environment.
This is partly true. Autism has always been with us. But except for the extreme cases(Rainman et al.) it has gone mostly unnoticed. This is because it has been easier to live with psychological problems like autism before. Our society has changed, and the change makes it a lot harder for a high functioning person with autism.
Living 200 years ago with Aspergers would probably not have been noticed, because society didn't have so many demands. Earlier in our history it was common to have a clear road of what to do. A very fixed school environment, with strict rules that had to be followed, you often took your fathers job(or else your father would send you off as an apprentice). Even getting a wife of children have for most of our history been something decided upon by the parents.
This means that the person with autism wouldn't have to make all these decisions, which means it is easier to live.
But now, from very early on there is choices. Choices about everything. There are no fixed guidelines. There is no one to decide for you. And there is a much rougher social world to interact with.
This means that living with autism is no longer as easy to hide as it was before. The problems are much more apparant in todays world.
The link with with VCRs in the 1980s is just an artifact. It is correlation(by coincidence), not causation.
The article goes on to state that researchers have found
a statistically significant relationship between autism rates and television watching by children under the age of 3
[1]
This is correlation, nothing more. A person with autism would be more prone to lock themselfes out of the stressing and confusion social world that we live in. So hidding in a computer game, or in front of the television is a lot easier, and a lot more comfortable. That is not to say everyone who does that suffers from autism. But there is a tendency for people with autism to do it more then people without autism.
Also from the article
"Several years ago I began wondering if it was a coincidence that the rise in autism rates and the explosion of television viewing began about the same time," Waldman said. "I asked around and found that medical researchers were not working on this, so accepted that I should research it myself."
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This makes it appear that he has a preconcieved opinion on the matter, and thus he would quite easily produce a report that supported his position. That is not to say he is a liar, a cheater, or a deciever. But it is normal for the human mind to try to work towards your belief. Because he has a preconcieved opinion on the matter that doesn't mean he can't do a proper study, he just has to be extra carefull and make sure to double blind everything.
The study(at 67 pages) starts off by ignoring the changes in society that has made autism more apparant(but not more numerous) in the last years. But it does include a token "some believe the changes in diagnosis criteria has made this change). But it is instantly abandoned because it offers no "trigger".
There is no good reason why the argument "The apparant rise in people diagnosed with autism has risen, amongst other reasons, because of a change in diagnosis critera" should be totally abandoned and thrown away simply because it doesn't give any etiology for autism. The argument still stands because etiology is above and beyond what that argument states.
Contrary to what the report states there IS a consensus that this is (atleast part) of the reason for the increase in the 1980s.
For checking when children watch television they went with "American Time Use Survay" that have established that "young childhoood television watching is positively correlated with precipitation".
So they have checked to see which years, and in which areas, it rained the most, and try to see if there is any correlation between that effect and the number of people diagnosed with autism.
And yes, they do find a correlation. But since the sample is only measuring the precipitation and autism rates in Washington, Oregon and California, i am not sure what that means, if anything.
NOTE: I am not good at math, and most of the graphs in the paper makes no sence to me. But the data being checked for here, only precipitation and autism rates, makes me dubious of this entire study.
The study is also working form the flawed assumption that there are more males with autism, than females. And it says that "the condition is thought to develop at hte latest by three years of age", which again is a common mistake.
While autism does indeed need to develop before the age of three, there is little to no evidence that anything happening after birth is an influence in autism. Just because autism isn't apparant and visible before the age of three it doesn't mean that the cause have to happen between birth and the age of three.
The study then disposes of the "refrigerator mother" theory, while not stating in which way their theory is different.
In fact, some authors claim that scientific findings clearly show that family environment plays no role (see, for example, Powers (2000)). In our reading of the literature, however, we have found no evidence that would support a broad claim that the family environment plays no role whatsoever in the onset of autism.
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While it is probably not prudent to say that "family environment plays no role whatsoever", i don't see any problem with saying "there is, thus far, no evidence of any family environmental component in the etiology of autism". And going on and saying "we have found no evidnece that would support a broad claim that the family environment plays no role whatsoever in the onset of autism" is not an argument in favour of anything, not even television, being a factor.
We need some evidence that the family environment plays a role before we can work on that assumption, something which the study neglects.
The study has four reasons to suspect television.
1) The California Data
2) TV and ADHD
3) "High Risk" Infants
4) The Amish
The California DataThe California Data shows autism rates since 1969, in contrast to national data. And it shows the increase that the study earlier talked about. The study then jumps directly into saying that
The timing of this growth matches quite closely with what was likely happening with early childhood television viewing.
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Matching "quite closely" with what is "likely happening" is working from conjecture, and nothing more.
The increase seen in The California Data can be explained with the reasons given here already. No further reasons are needed.
TV and ADHDA study has shown correlation between watching television and getting ADHD. From the study we are talking about here they say
Note that the study, although quite suggestive, is not definitive concerning the effect that early childhood television watching has on the onset of ADHD because of the nature of the methodology employed. In particular, the study does not employ a controlled experiment or a natural experiment to look at the issue. Rather, the authors used evidence from government-sponsered national health surveys to show a correlation between early childhood television watching and behaviour at age seven consistent with a diagnosis of ADHD. The problem is that cause and effect may potentially be reverse of how the authors interpret their results.
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This is quite correct. One wonders why they still use this study as evidence in their favour. And why they haven't made sure to evade that trap themselfes.
Instead this study does exactly the same thing as the study they quote.
"High Risk" infantsOur hypothesis that early childhood television watching is a trigger for autism is more plausible if infants who are at "high risk" of becoming autistic exhibit behaviour consistent with vulnerability to television viewing. For example, such a behaviour might be that high risk children have more difficulty disengaging from watching television once they begin watching.
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The first problem with this hypothesis is that they state what they think high risk behaviour might be. They don't say what it is, because they haven't investigated it.
Secondly they have cause and effect reversed. The children have trouble disengaging from watching television because they have autism. This is quite common with people with autism, and not only in the 3-6 age group.
Many parents to children with autism will try the scenario that they tell their children that "you have to come eat now, there is food now", and the child(or teenager) replies "no".
This doesn't mean "no, i don't want to eat", this means "no, i am in the middle of something, i can't come now, give me 10 minutes and i will be ready". This is because people with autism aren't as flexible as people without autism. And it takes a little while to get used to a new situation. This is the reason the children say "no" to go eat now, they aren't flexible enough to change situation.
And that is the reason that the children can't disengage from watching television.
The AmishFor religious reasons the Amish do not use electricity and so young children in that population watch no or at most very little television. Thus, our hypothesis that early childhood television watching is an important trigger for autism suggests that autism rates among the Amish should be distinctly ower than in the rest of the population
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For reasons i have stated above it would be expected to have a lower amount of people with visible autism in a society like the Amish. Not because they don't have television, but from the simple fact that it is a simpler, less confusing, and less demanding, society to live in. The people with autism are still there, but since they haven't got that many demands on requirements it isn't as visible as it is outside of the Amish culture.
It is not required to be as flexible in the Amish culture as it is in the general population. The demands are different, and because of that the evidence of autism isn't as apparant. But there are still people with autism in the Amish culture. Just like there have been through most of human history. It is just only the most extreme cases that are visible.
Links:
[1]
TV Really Might Cause Autism
[2]
DOES TELEVISION CAUSE AUTISM?
From my page:
http://www.autismmyths.com/index.php?na ... cle&sid=22
Again, sorry for it not being totally on topic with the mercury thing, but i still feel it have some valuable data.