You’ve definitely heard of autism.
What you might not know is what it is, and what causes it. Or why it’s become increasingly common over the past ten years. And could the MMR vaccine be responsible for causing it?
This blog will explore these issues over the next week or so.
What is it?
Autistic behaviors are typically noticed in young children when they behave oddly and fail to reach important landmarks in social development.
The main three ways that children behave on the autistic spectrum is 1) Restricted and focused interests 2) difficulty communicating and 3) difficulty with social interactions.
Any one of those behaviors taken by itself does not mean autism. It’s when they are combined, persistent and extreme, however, autism is indicated.
We don’t know what causes autism. The old school theory was to blame the parents, similar to how parents used to be blamed for schizophrenia. Emotional environment can play a role in autistic development – but typically only if it is extremely bad. Serious emotional deprivation, for instance, or trauma can cause behaviors indistinguishable from autism as seen in studies of Romanian orphans.
The vast majority of parents are loving and caring.
Research shows that genetic factors play an important role. Some of the most important information we have on autism’s genetic link comes from studies of twins. Twins can be either monozygotic or dizygotic. That sounds complicated but it’s really quite simple.
The twins can be from one egg that splits into two fetuses, or from two separate eggs. If they come from the same egg, they are identical genetically. Otherwise, they are genetically as similar as any two siblings.
The data show that if one of two twins from the same egg, and thus has the exact same DNA, is autistic, the other has a 60% chance of being autistic. This roughly means that 60% of autism can be explained by pure genetics.
Autistic children seem to have difficulty with processing and recognizing faces. This difficulty arises as they age and start to miss developmental landmarks. Almost all children are born with the instinctual ability to recognize human faces. Autistic kids, however, don’t learn to recognize facial features as quickly as they should.
That is just one of many developmental landmarks that are challenges for these children.
Part of the problem may be in low levels of Oxytocin. Oxytocin is a neuropeptide that plays a role in developing emotional bonds. Levels of oxytocin, for instance, increase during sex and after having a baby (presumably to create a bond with the child). People dosed with oxytocin are also more trusting of strangers in experiments.
Low levels of oxytocin can be caused by genetic factors and may play a role in autism.
Autistic kids have differences in how their senses handle information, but we don’t know why, and what that means for their development – and how to help them. One such difference is hypersensitivity to noise. Noise sensitivity can vary wildly – from completing ignoring what people say and possibly getting labeled as deaf, to cringing at quiet noises.
Next article: Do Vaccines Cause Autism?
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