What causes autism: An Overview

William Stillman, from The Autism Answerbook, outlines the general causes to this tangled and unsolved question. However, The Autism Answerbook was published in 2007, and thus by now it is outdated in light of the recent discoveries.

Autism is a result by a general chemical imbalance. The causes to this imbalance are many, but two are generally debriefed below.  

Genetics.  Autism's are tangled and many undiscovered; "Autism is not a disease, but a syndrome with multiple nongenetic and genetic factors." (2) The most compelling point [is] genetic susceptibility." For example, he explains, "there's a 3 to 8 chance of having a second child with autism, and a 30% greater likelihood that identical twins will be autistic than fraternal twins." Additionally, "autism is four to five times more common in males than females." (3)

Aside from probability, inheritance also may also increase autism's expression. By 2012, much research has been done to confirm that genetics does indeed play its role in autism's manifestation. However, also by 2012, the rate of autism's diagnoses (needs to be specified as thus), has experienced an exponential increase which cannot only be held accountable by genetics. Genes do not change that fast. 

Environmental Factors. To also account for the exponential increase, scientists have pinpointed some environmental conditions which could lead to autism's development. 

To name a few: 

• viruses (3)
• mercury preservative (3)
• Thimerosal (3)
• mumps-measles-rubella (MMR) childhood vaccine (3) 
• pregant mothers' exposure to toxic pollutants (3)
• household products (2) -- chemicals and cleaning products
• polychlorinated biphenyls (2)
• lead (2)
• brominated flame retardants (2)
• pesticides (2)

Sources: 

1. The Genetics of Autism (http://www.ncbi.nlm.nih.gov/pubmed/15121991) 

2. New Study: Autism Linked to the Environment (http://www.scientificamerican.com/article.cfm?id=autism-rise-driven-by-environment)

3. The Autism Answerbook by William Stillman

Potentially Autistic: Anonymous

I know a dear boy who will go by the name, Timothy, to protect his anonymity. He's turning thirteen this year and I've known him for all of my life. His family and my family are particularly close. I've spent my childhood with Timothy. During the summer months before my age was double digits, my brother and I would literally camp out in his house in a play tent we all shared, living the entire day in that tent on solely crackers and ham. 



After finishing The Autism Answerbook a month ago, I have been noticing certain behaviors that Timothy has that before, I just ignored. Now gaining knowledge of their attribution for autism, I'm beginning to question some things I had always overlooked.


-- Timothy often doesn't share eye contact in conversation. Personally, I know I don't do the same. Sharing prolonged eye contact feels uncomfortable to me, but Timothy's eyes often wander and sometimes, don't even look up to mine. I've learned that while we normally assume lack of eye contact with lack of attention, Timothy does listen to every word I utter. Research has shown though that "if a child is compelled to maintain direct eye contact, he may not be hearing a word, but if your child appears not to be listening, he is most likely absorbing nearly everything you are saying.


-- I often feel like Timothy is a cartoon character in his mannerisms and his speech. Though he is turning thirteen this year, he is still very immature. We watched Arthur throughout our childhood and he still does. Sometimes, I often feel like he has adopted Arthur's mannerisms. For example, he'll interact with his younger sister the same way Arthur interacts with D.W. Additionally, his speech is very similar to Arthur's -- the formal, yet reasonable tone, saying "you know" a lot, just like Arthur had. It seemed like his character was based on a character on the television.


Additionally, Timothy is very much absorbed in his video games. As far as I can remember, he has been completely obsessed. He would repeat things that Mario and Luigi would exclaim, or shout phrases from Call of Duty (sans explicit words). This video game obsession seemed typical for a boy, especially in the world we live in today. And his tendency to act like the characters -- I simply dismissed it as child role-playing, just like I had wanted to be Mulan as a young girl. 


At first, I had dismissed Timothy as just being a normal and innocent boy. However, after reading this question, I began to consider otherwise: "What do I do about my child's habit of repeating things that characters in video games, commercials, and cartoons say?" The answer says that this adoption of personas is a building block to cultivate functional spoken language. And perhaps, with the help of a therapist, that functional language can be achieved.


-- Timothy has always been scared of loud noises. Now, I don't want to stereotype, but often, boys of his age enjoy explosions and "boom!" of sorts. However, since he was young, he cower at the sound of fireworks, fire alarms, police sirens, and vacuum cleaners. Even now, he plugs his ears at these sounds. Perhaps he is simply audio sensitive, or perhaps, he experiences "sensory sensitivities," a common criteria for autism. It is "uncomfortable, painful, or upsetting sensations you receive in reaction to sensory stimuli that are beyond your tolerance threshold. 


-- Timothy's handwriting has always been awful. In the Vietnamese culture, handwriting is truly treasured, perhaps for its calligraphic style of writing in the homeland. His parents have always made him practice handwriting on those dotted line sheets, even up until now. Still is handwriting is only borderline legible. Autism addresses a difficulty with handwriting, known as dysgraphia. It is the "inability to produce discernible handwriting, and may include elements of dyslexia due to numbers and characters being reversed, out of sequence, or written upside down." The scientific explanation would be the inability for brain-body connections to successfully interact.


-- Timothy used to and still has a very limited diet. As a child, his diet consisted of fried chicken and fries, cheese pizza, and chocolate chip cookies. Today, he has improved, eating tofu and rice, spaghetti, broccoli on the side. The "answer" addresses that "eating only a very limited diet is a common experience among children with autism" as they have a "very limited palate"(from their sensory sensitivities). 


I've only covered half of the Timothy's noticed characteristics and only half of the book in explanation. However, I feel like this is ample enough to consider potential autism. Albeit, I am a researching high school student and perhaps these characteristics I have noticed are simply warped interpretations I've contrived in my eagerness to learn more about autism. Perhaps the strict diet is simply just a boy being picky. Perhaps the illegible handwriting is simply a lack of artistic ability in that particular subject. Or perhaps it is something much more.