Causes of Autism

Introduction

Since the first time it was identified as a disease, which is categorically different from schizophrenia, enormous studies have been carried out to identify the causes of autism. Scientists have been attempting to obtain the best answer of what causes autism. They come up with results, hypothesis, speculations, which some of them are quite veritable, but yet appear to be flaw and incomplete. For instance, economists from the Cornell University, who carried out a study on autism, presented their controversial research result to public and clearly stated that TV is the cause of autism (Easterbrook 2006, pp.1-3).



Issues on autism are very interesting. Moreover, the arguments about autism amongst scientists from different backgrounds have always been grabbing people’s attention. Autism spectrum disorders is defined as developmental disabilities, which includes classic autism, Asperger’s disorder and other specific conditions that can be grouped with it by The Centers for Disease Control and Prevention in The US (Berg 2009,p.14). Derived from its definition, children that are autistic, undergo disabilities on their social and cognitive behaviour, affection and communication. Berg (2009, p.14) claims that “The severity of the condition varies greatly, as does the exact constellation of symptom”. Perhaps this is also one of the reasons why autism seems to be such a bulky puzzle that is very difficult to solve.

What are the definite causes of autism? Which has the biggest influence on causing it? Is autism mainly because of genetic disorders? Related to these questions, this paper essentially aims to discuss the causes of autism. Each causes can be considered as pieces of the big puzzle of autism that will construct the big picture of it. The discussion is based on a review of several articles which present causes of autism from a different point of view and backgrounds.

Pieces of the Autism Puzzle

Since its early exposure as a pandemic, autism incidents have been associated with vaccination. People believed to studies that correlated figures of vaccination given to children and figures of autism, which at that moment appeared to be very logical and interrelated. Berg (2009, p.15) explains that “The case against vaccines is sometimes based on the presence of mercury in thimerosal, a compound used as a preservative in some vaccines”. Research proved that mercury has an effect on causing brain damage which potentially can cause autism. Thus, if a child is vaccinated, he or she is at risk of becoming autistic.

The long debate of vaccine and autism was not only because of thimerosal, but also its substances. Berg (2009, p.15) stated that “One CDC-funded study has also considered the possibility that the measles virus in the MMR vaccine might lead to autism by causing a persistent intestinal measles infection”. The thimerosal issue and the study about MMR somehow converge into the idea that vaccination is causing autism.

Numerous research have been done to provide evidence on the definite link between vaccine and autism, but the outcome arrived on the scene was the opposite. Even more so, although the suspected substances in vaccines were excluded, the autism incidents have continued to increase (Easterbrook 2006, p.1). In addition, Allen (2005, p.1) also claims that “four perfectly good studies comparing large population of kids have showed that thimerosal did not cause the increased reporting of autism”. This fact, then, somehow become a basis for scientists to continue to search other pieces of autism puzzle.

A controversial research done in California, Oregon, Pennsylvania and Washington State by researchers from Cornell University proved that autism increased in areas that also have a high frequency of TV cable viewing. The researchers analyzed the growth of cable TV access and autism rates in a 17 years period in California and Pennsylvania and they concluded that the approximate 17 percent increase in autism in both areas was due to the increase in the viewing of cable TV. Furthermore, supported by the studies carried out by The Bureau of Labor Statistics on behavior, the study also found that in counties that have high precipitation the incidents of autism are high as well.

However, it was difficult for other scientist to admit that The Cornell study has traced out new clue, that widespread autism occurrence was a consequence of an excessive exposure from certain objects on children, and TV viewing might be the answer. The researchers, who are economists, accused to disregarded essential factors that can cause autism and the rise in autism incidents. As stated by Wallis (2006, pp.1-2), the measurement used in the research was wild and indirect because the data were weather reports and subscriptions of cable TV. Furthermore, the fact that the researchers ignored the need for an exact measurement on TV viewing frequency, led Wallis to call the results “oddly definitive conclusions” (Wallis 2006, p.2).

Prompted by its complicated traits as a disease, scientists have always been scrutinizing on genetics and neurobiology aspects. Michael Cuccaro, a psychiatrist from Duke University who specializing in autism, stated that “It was thought we could identify the causes if we could understand those connections, but we’re still left searching for causes. There was a missing piece of the puzzle, which was the environment.” (Cuccaro 2004 quoted in Parsell 2004, p.311). It is quite an ease knowing and grasping the theory that environment also plays a role in autism. Perceptibly, environment is comprised of many factors which have their own predisposition to cause autism. In terms of environment, scientists also included fetal or the womb environment during pregnancy rather than postnatal environment solely.

A pediatric neurologist, Zimmerman, thinks that contribution from the environment influences the fetal development by disturbing its normal growth and may ended causing autism (Parsell 2004, p.311). As instance, Parsell (2004, p.311) mentioned Beth Crowell, a mother of triplet autistic children, as an example of the possibility that autism can be triggered since pregnancy. Crowell strongly believes that terbutaline has a possibility to cause her children became autistic. Her claim was considered as reasonable because an investigation carried out by researchers has shown that there is a connection between terbutaline and incidence of autism. However, Connor stated the alteration of fetus neurodevelopment which may lead to autism can also be triggered by factors derived from the pregnant mother herself and the most possible factor is hormones (Connor 2004 in Parsell 2004, p.312).

Conclusion

In Conclusion, stating that there is an association between internal and external factors which eventually cause autism is still an inadequate hypothesis, because there are gaps in between that need to be elucidated. However, Julie Daniels, an assistant professor at the University of North Carolina Gilling School of Global Public Health, wrote a statement which published as an editorial in one of the health journals, “There are probably many combinations of genes and environmental factors that contribute to the constellation of autistic traits” (Daniels 2006 quoted in Berg 2009, p.16).

As there are always differences in every case of autism suffered by an autistic child, diverse sign, symptom, degree, certainly there is also specific cause of it, which in many cases independently related only to the case. Although currently scientists have identified many factors that trigger or cause autism, still, to construct them solidly as the definite cause is unfeasible. There is no distinctive or trivial factor in the pieces of autism puzzle, they are affecting each other, scattered and remaining to be solved in the future.

References

Allen, Arthur. 2005,’ Sticking Up for Thimerosal’, retrieved 28 July 2009, .

Berg, Rebecca. 2009, ‘Autism-An Environmental Health Issues After All?’, Journal of Environmental Health Vol. 71 Number 10, June, p.14-18. Available: http://proquest_1732150551[1].pdf

Christakis, D.A., Zimmerman, F.J., DiGiuseppe, D.L., & McCarty, C.A. 2004, ‘Early Television Exposure and Subsequent Attentional Problems in Children’, Pediatrics Vol. 113, April, pp. 708-713.

Easterbrook, G. 2006, ‘TV Really Might Cause Autism. A Slate exclusive: findings from a new Cornell study, retrieved 22 July 2009, .

Parsell, Diana. 2004, ‘Assault on Autism’, Science News. Vol. 166, Iss. 20, November, p. 311-312.

Wallis, C. 2006,’Does Watching TV Cause Autism?’, retrieved 28 July 2009, .