What causes autism? Some theories.

What causes autism? Some theories.

Debate over what causes autism, and how to prevent it from occurring, remains inconclusive. Theories range from biological factors, to medical interference, and even to how a child was raised in early life.

The vaccine myth.

The theory that vaccines cause autism is unfortunately popular.The article published by Andrew Wakefield in 1998, which suggested the Measles, Mumps, Rubella vaccine (MMR) was responsible for behaviour regression and developmental disorder, was repeatedly refuted and eventually retracted in 2010.

The vaccine theory relied on two factors: one, that children often displayed autistic symptoms around the same time as receiving the MMR vaccine; and two, that autism had become ‘epidemic’ as vaccination became common practice in society. The more likely reason for the surge in autism diagnoses is a better understanding of the condition, changes to diagnostic practices and increased awareness–particularly among educators.

That autistic symptoms arise in the same developmental period as the second dose of the MMR vaccine (usually around the age of 4) is purely coincidental.

Even if the vaccine theory was correct, and I don’t believe it is, I fail to understand the logic of refusing to vaccinate children to decrease the risk of developmental disorder. Autism isn’t exactly a fun bag of kittens every day, but it is perfectly possible to live a long and happy life as an autistic person. Even those requiring extreme care are capable of being happy and healthy people.

Refusal to vaccinate increases the risk of contracting avoidable (and deadly) disease, both to the unvaccinated child and those who are unable to be vaccinated for medical reasons. It just doesn’t make sense to me.

Vitamin D deficiency.

This one is interesting, because I have extremely low levels of Vitamin D. I know, I know–I should go outside from time to time.. but maybe that’s not the only factor? I take supplements daily, which I find gives me the energy boost I’m often lacking.

Women who are deficient in Vitamin D during pregnancy are more likely to give birth to a child with autistic behaviours.

Inability to properly absorb and process Vitamin D may also be one of the many genetic factors that contributes to an autistic profile. Deficiency in Vitamin D may not be a cause, but a symptom–and perhaps lead us to a genetic marker as we build a greater understanding of how autism occurs.

Genetic factors.

This is the theory that makes the most sense, both in logic and in my own family experience. Autism is a condition of particular traits, that by their combination and intensity in a single person cause that person to diverge from what is known as ‘neurotypical’ (NT). You could think of this combination as a recipe, almost.

In most cases, and definitely in mine, you can spot autistic traits across the family of a diagnosed person. While the behaviours may be similar, they may not have the same intensity, obsessiveness, or rigidity of the autistic person–but they’re certainly there. Some in the family may have an autistic trait or two that is extremely intense—but not any others.

These traits are spread among parents, aunts, uncles, grandparents and beyond. When enough intense traits are passed down to a single person,  that person becomes diagnosably autistic.

This also explains why many people feel everyone is ‘a little autistic’, which is in some views true–and others false. Milder examples of autistic behaviours are common among the general population.However, while an ‘allistic’ (non-autistic) person may understand elements of a behaviour, they are less able to understand how multiple intense traits affect an autistic mind.

So you may think of autism as caused by the right mix of ingredients passed to an individual.

Interestingly, my genetic profile is significantly different to those of my undiagnosed siblings. I am the only right-handed child, the only one with grey eyes (the others are brown), and of us four I have the shorter, thinner-boned build. These genetic differences between me and my three siblings hint at my getting a number of recessive genes, some of which may have been autistic markers.

Brain compensation theory.

This does fall in with genetics as well, but an interesting study on autistic children and their non-affected siblings discovered that unaffected siblings also have a similar neurological signature to their autistic sibling.

Decoded, that means that the structures of the brain used to process particular information have a similar decreased ability as compared to children without an autistic sibling. However, unlike both their autistic sibling and their typically developing peers, unaffected siblings showed activity in other areas of the brain.

That suggests that unaffected siblings have created ‘other’ pathways through the brain to achieve neurotypical behaviours. I love this, because it shows just how adaptable the brain is. It also firms up the nature of autism as genetic, and explains how siblings can exhibit similar traits to their autistic sibling but not at the same intensity. Some compensatory structures may not be as complete as others, meaning that the trait will be more present in that sibling.

I find this especially interesting, as my sister is highly sensitive to tags and seams in her clothing. Far more than I am! That sensory sensitivity may be a trait that her brain has not fully countered.

Nurture and autism.

I’ll talk a little about this, because I think it’s relevant. Autistic behaviours can be adjusted over time, especially among those in the Aspergers category. I believe that autistic people are capable of building their own compensatory structures in the brain. We need to find our own way to achieve stability. This doesn’t mean a cure–simply working with and around our weaker points for a solution that suits us.

Early intervention and parenting methods are critical here, which is where I feel extremely lucky. Though I didn’t know I was autistic until a few months ago, my parents were not the sort to give in to picky eating habits. You ate what was on the table, or made your own food. I believe the firmness of that rule is one of the primary reasons why there are so few foods I don’t eat–I was never able to avoid anything long enough that it tasted wrong/unpleasant.

As an adult, I allow myself to not eat the things that really do bother me: pork, any meat with bones still in it, any meat that still resembles the animal it used to be, celery, and zombie toes broad beans. The list of things I won’t eat is actually quite small. I will pick around bones, but I really don’t like it. I’ll also eat mashed potato, though the texture bothers me most times.

I believe my lack of serious food aversions is mostly due to being encouraged to try a wide variety of foods as a kid, and also my curiosity regarding taste. New foods and drinks intrigue me, so I have to try things at least once! Or perhaps, it was simply never a severe factor for me.

We were also raised in a very structured and supportive environment, and the only real upsets I can recall having usually involved things like moving house, moving school, and other unavoidable moments of change. For the most part, my family life synched well with the parts of my autism that liked things to be a certain way, and for things to happen in a way that was consistent and predictable.

We went to school through the week, to bed at a particular time (even when I was in my last years of high school, I had a bed time. I hated it, but looking back it was another part to the structure of my day that I could rely on), there was often sports on Saturday morning, and during the football season we would generally catch up with family friends to watch the game and eat together.

So I was lucky in a lot of ways, that my family created an environment that curtailed some of the more annoying aspects of autism, while providing the structure I needed to feel secure. Though at the time, it was simply how our family operated–not any concession for an autistic mind.

I give in to it more as an adult, especially with food and clothing. I buy my own, so if I find that I’ve purchased a shirt that is uncomfortable and distracting to wear–it’s my own loss if I never wear it. The same goes for food. Clothes get rotated to the back of my wardrobe and eventually donated to charity. Some are too itchy, some feel too restricting, and some just make me irritable and I can’t articulate why. I did get myself to wear skinny jeans, though I prefer not to–and I still won’t wear shorts. I don’t even know why I won’t wear shorts, I just hate them.

I can make these choices as an adult, because I have been through the process of attempting, tolerating, and know for myself if it’s worth persisting. I also know I can work around things, like eating all the peas first when someone mixes them with the marvel that is corn (why do people ruin corn like that?). I’m in a space where I can do things in my particular way, and so long as it doesn’t hamper my ability to get things done, there’s nothing wrong with that.

I’ve rambled a lot and gone way off point–each autistic person’s ability to adapt and build compensatory structures and strategies will depend on the severity of the symptom, awareness of the individual in working toward the goal, and the age of the person. It can be done, though, it’s up to the individual to decide whether there is value in being able to eat a food, tolerate a situation, or wear an item of clothing. Sometimes the level of work to get to a point of tolerance isn’t justified for the outcome, or the time and number of exposures it would take to achieve the goal (remembering that each exposure will cause some level of distress) isn’t worth it. While it’s definitely ‘possible’, it may only be after thousands of exposures and unknown distress.

Are there any other theories you’ve heard regarding causes of autism? I’d love to research them!

 

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