Light it up!
From Empire State Building to the Sydney Opera House, iconic landmarks around the world are shining blue at night in honor of the sixth annual United Nations-sanctioned World Autism Awareness Day. "Light It Up Blue" is a global-initiative lead by Autism Speaks and spans throughout April as part of Autism Awareness Month. There is no doubt that the general public is aware of autism spectrum disorders (ASD). The topic of autism has been covered in various media outlets including film and television (even soap operas! "Days of Our Lives"), news, and popular culture. However, general awareness of the disorder has not necessarily translated to "correct" perceptions about the etiology and ontogeny of ASD. Jenny McCarthy and her dangerous anti-vaccine crusade, for example, certainly raised awareness about autism but at a massive cost to the field, not to mention public health, by suggesting a causal link between vaccines and ASD. While the scientific community has provided evidence that this cannot be further from the truth, the fact that there is still discussion about vaccines highlights the disconnect between two groups who undoubtedly have intimate experience with the disorder--parents and researchers. In light of this, I think its crucial that the scientific community raises awareness about autism, especially to the families and individuals directly affected by autism and their supporters.
In honor of Autism Awareness Month, here is some basic information about ASD.
1. What is autism? How is it diagnosed?
Autism Spectrum Disorders is characterized by deficits in social communication and social interactions, and the presence of restricted and repetitive behaviors. While the precise diagnostic criteria varies by diagnostic manual (e.g. DSM IV to DSM V; ICD 10), there is great consensus of the clinical presentation of ASD. The onset must appear before age 3 with delays or atypicalities in social interactions, functional language or symbolic play. Current "gold standard" diagnostic instruments are the Autism Diagnostic Interview-Revised (ADI-R), a semi-structured parent interview, and the Autism Diagnostic Observation Schedule (ADOS), a play-based interaction.
Most research studies use the ADI-R, the ADOS and additional cognitive or behavioral assessments to characterize a child as having ASD based on a clinician's best estimate. In reality, social skills follow a normal distribution and the categorical label of ASD discretizes a continuous spectrum. Individuals who have sub-threshold symptoms of ASD may be characterized as having Pervasive Developmental Disorders-Not Otherwise Specified (PDD-NOS). While it is possible to receive a diagnoses by 12 months of age, the average age of diagnosis in the U.S. is 5 years. That time difference represents a huge loss of opportunity for early intervention and behavioral treatment, both of which may change the trajectory of the disorder. 2. What is the incidence rate of ASD? The Centers for Disease Control and Prevention (CDC) just released a new number. They estimate that 1:68 children in the U.S. have an ASD. This is a whopping 30% increase from 1 in 88 two years ago. The CDC has determined this statistic is by evaluating health and educational records of 8-year-old children in 11 states. This number is far from perfect. Written records cannot definitively determine an autism diagnosis. But the new statistic potentially reflects increased awareness in healthcare professionals in identifying and diagnosing children.
3. What causes ASD? NOT VACCINE!!! Researchers are still looking into the roots of the disorder. Some things are clear though. There is a strong genetic component to the disorder. Infants who have an older sibling with a confirmed diagnosis of ASD have a 20% chance of also developing the disorder. Autism is more prevalent in boys than girls--for every 4 boys, 1 girl is diagnosed. This suggests some sort of female "protective" factor to genetic liability. However, girls that do receive an ASD diagnosis generally have more severe symptomatology than boys.
Autism is recognized as a neurological disorder. A recent paper reported that brains of children with autism contain patches of immature neurons in cortical areas involved in high-level cognitive function. Researchers of the study sliced and stained postmortem brains with markers that flagged genes expressed by various neurons and support cells. During fetal development, neurons align themselves into a column with 6 discrete layers. What was particularly striking about this study When the researchers computationally reassembled the slices to reveal the layering architecture, they found that some of the cells were in the wrong layers, suggesting that abnormal prenatal brain development may underlie the disorder. This opens a lot of questions about mechanisms leading to abnormal brain development, genetic markers, and why outwards behavioral manifestations aren't apparent until the first year.
4. What is the current trend in research?
Many scientists around the world are directing their focus in uncovering earlier markers of the disorder to improve diagnostic ability and therefore the prognosis of the child. One of the huge benefits of early detection is early intervention, in which a child works on improving social skills, language, and adaptive behaviors.
Other researchers are developing new interventions that leverages individualized and restricted interests.
UCLA is an Autism Center of Excellence (ACE) funded by the National Institute of Child Health and Human Development (NICHD). The goal of one project is to reliably identify biological markers of ASD by prospectively following infants at high and low risk for the disorder from 6 weeks to 36 months. The Infant Sibs project is studying the development of social attention and implicit learning through converging behavioral and neuroimaging methods. The study is still recruiting families! 5. How can I help? Support the cause and spread the word about Autism Awareness Month! Inform people you know to get involved in autism research. Hopefully this primer was helpful in shaping your understanding of ASD.
Here are some additional links: