Science
What Doesn't Cause Autism?
Published July 29, 2009 @ 02:27PM PT
Now that breast milk is being pointed to as a cause of autism based on research on rats by University of California neuroscience professor Michael Merzenich (a 2007 study found developmental abnormalities in rat pups who were nursed by mothers who had been exposed to certain PCBs during pregnancy and in the early weeks after giving birth; more discussion at About.com)----and me having noted a very wide assortment of purported causes of autism (TV, ultrasounds) in my past four years of daily blogging---one wants to throw down the proverbial gauntlet (if not throw up one's hands) and say what hasn't been suggested as a cause for autism?
You are welcome to note potential future candidates for the title of "autism cause of the moment" in the comments.
What is Sally Anne Thinking?
Published July 28, 2009 @ 09:35AM PT
A recent study published in Science theorizes that in AS the capability for understanding mental states exists, just not spontaneously. This conclusion is drawn because study subjects only "passed" a Sally Anne False-Belief Test when verbally prompted, and not spontaneously with their eye gaze.
Deconstructing assumptions a bit (and admitting I have not had time to read the primary source), there are, of course, some questions. How is it known that eye gaze in AS subjects means the same thing as eye gaze in subjects who do not have AS? Particularly as eye gaze is something that often marks people on the spectrum as visibly different? Particularly as movement and perceptual differences are also often noted? How is it known that eye gaze in AS subjects means the same thing as eye gaze in subjects who do not have AS in relation to this particular false-belief task?
If the verbal prompting appears to refute the idea of "mind blindness," then why is it not possible that it does, in fact, simply refute the idea of "mind blindness?" Why is it necessary to hang onto the notion that mind blindness must exist, there is no other explanation for "social deficit?" The fact that "mind blindness" is often a given when talking about autism does not make "mind blindness" itself a fact.
In fact, there is an interesting paper Does the Autistic Brain Lack Core Modules? that deconstructs the "mind blindness" idea further, including discussing language-based versions of the false-belief test. That paper not only discusses deep issues with the concept of mind blindness, but also some issues with assumptions about eye gaze.
Building on existing theory is an essential in science. But also essential is questioning the existing theory itself.
"Mind blindness," regardless of what the press may say, is not a done deal. The question remains open. There are other equally (more so?) plausible reasons for both differences in social communication and for autistic responses to false belief tests.
A Gene for "Problem Behaviors"?
Published July 24, 2009 @ 12:43AM PT
The topic of genes and autism often seems to be as much about controversy as it is about science. Studies of the genetics of autism (like this recently reported one) often only seem to have identified genes in a small set of individuals; further, so many genes are pointed to as potentially linked to autism spectrum that the thought of anyone ever honing in on some specific "autism genes" seems quite beyond reach. Then, too, should any specific genetic markers for autism be identified, questions about prenatal genetic testing and eugenics with huge ethical implications arise.
A new study linking certain genetic markers to "problem behaviors" in adult males with developmental disabilities highlights all of these concerns; further, it's important not to say that "problem behaviors" are only the fault of the person displaying these, but may well be due to other factors (including how that person is treated and perceived).
105 white men between the ages of 18 and 50 were participants in a study of the gene enocding monoamine oxidize A or MAOA, MAOA is, as noted in the July 23rd Science Daily:
......involved in the regulation of the neurotransmitter serotonin, which is linked to appetite and mood, and the neurotransmitter and hormone norepinephrine, which is linked to the fight-or-flight response. Previous studies found that variations in MAOA were linked to violent behavior.
MAOA has also be linked to "autism in children, autism severity and communication problems."
Science and the Dark Ages
Published July 23, 2009 @ 12:16PM PT
Yesterday, in a meeting of autism researchers I attended, a researcher described people with Retts as having "no souls." That Retts "takes the souls" of girls. The researcher said this without malice; in fact, I had the strong sense that he felt this description was in some way compassionate. When it was recommended to him by another researcher who does a lot of work directly in collaboration with the disability community (not me though I was sure thinking it) that he might want to meet some real girls with Retts to see that they do, in fact, have souls, he related how meeting the father of someone with Retts is what inspired him in his mission to return these girls' souls.
Relating this to a friend later, my friend asked, "did he really mean that literally, like a religious thing?"
I've no way to know for sure of course, but my suspicion is that it wasn't a religious thing; that the word "soul" was more likely being used as a synonym for "personhood" or "humanity" or "that which makes a person a person."
The mix of souls with science harkens back to the ages before a separation between the mystical and the scientific. But there's a more recent dark ages involving lack of understanding, inclusion, or respect for people with disabilities in discourse about their own lives. Of viewing people with disabilities as broken things, and not as human beings.
While the Renaissance may be here, we're still not fully out of those dark ages, or else the term "soulless" would be as abhorrent when applied to someone with Retts as it currently is applied to someone from a minority racial or ethnic background.
Increased direct involvement of the disability community in research is one way to start lighting this darkness; however, it's hard to motivate people to become involved when they are labeled in disparaging ways like "soulless." I know I certainly wouldn't participate in any sort of research--not as a participant and not as a colleague--from someone who feels that Retts "steals souls." Something else, or more, or just different may be required to bootstrap some segments of the research community into a more modern paradigm.
27 genes
Published July 16, 2009 @ 02:15PM PT
27.
That's how many genes might be "associated with either Asperger Syndrome (AS) and/or autistic traits and/or empathy" according to a new study in the July 16th Autism Research. Led by Dr Bhismadev Chakrabarti and Professor Simon Baron-Cohen from the Autism Research Centre, researchers identified 68 genes because they were associated with:
(1) neural growth
(2) social behavior
(3) sex steroid hormones (e.g. testosterone and estrogen)---these were chosen because of the higher incident of Asperger's in males than in females and because of research by the ARC about fetal testosterone levels and autistic traits and empathy in typically developing children
As described in yesterday's Science Daily, the genes of 349 adults who had completed the Autism Spectrum Quotient (AQ) and the Empathy Quotient (EQ) were compared to those of 174 adults with a formal Asperger's diagnosis. The results:
The research found that single nucleotide polymorphisms (SNPs) in 27 out of the 68 genes were nominally associated with either AS and/or with autistic traits/empathy. 10 of these genes (such as CYP11B1) were involved with sex steroid function, providing support for the role of this class of genes in autism and autistic traits. 8 of these genes (such as NTRK1) were involved in neural growth, providing further support to the idea that autism and autistic traits could result from aberrant patterns of connectivity in the developing brain. The other 9 genes (such as OXTR) were involved in social behaviour, shedding light on the biology of social and emotional sensitivity.
A comment by Prof. Baron Cohen about why the study looked specifically at individuals with Asperger's Syndrome:
"We chose to look at the genetics of AS because all other genetic studies have focused on classic autism, which can include learning difficulties and language delay. AS is a more 'pure' condition because these other factors are absent."
Neural functioning, social behavior, and hormones (specifically testosterone) are being pinpointed as particularly characteristic of Asperger's and, perhaps, of being on the autism spectrum. It's quite apparent that there is something different--dysfunctional, if you will---about my son's neurology; it's quite an understatement to say that he struggles socially. (I'll refrain from going into testosterone; certainly it's been a topic around here as my son is an adolescent.) His limited language/communication and cognitive abilities make testing and evaluation always a bit more of a challenge for Charlie, and also make it harder to figure out if he's not (for instance) responding because he doesn't understand a question, or because he can't retrieve the words quickly enough to answer.
There also seems to be the whiff of a suggestion here that neural functioning, social behavior, and hormones have something in particular to do with the autism spectrum. This is of interest in light of the proposed revisions to the DSM regarding how autism is defined with regard to "severity."
27 genes found, at least 20 more questions to ask.
Laugh and Be Happy
Published July 13, 2009 @ 04:00PM PT
Apparently there are two types of laughter--laughter as an unconscious expression of joy, and laughter as a conscious expression of social information. Guess which one an Ithaca study found autistic children do much more of? The good news for us is that people prefer listening to the unconscious, spontaneous type of laugher that many of us on the spectrum excel at. Spontaneous laughter is the sound of happiness.
On the happiness topic, a University of North Carolina, Chapel Hill study is all about how short, frequent moments of happiness lead to resiliency and well-being, that, as quoted from researcher Barbara Fredrickson),
"Those small moments let positive emotions blossom, and that helps us become more open. That openness then helps us build resources that can help us rebound better from adversity and stress, ward off depression and continue to grow."
...The study helps show that to be happy, people do not need to adopt a "Pollyanna-ish" approach and deny the upsetting aspects of life.
...Fredrickson suggested focusing on the "micro-moments" that can help unlock one positive emotion here or there.
Something probably especially important for those of us who live with a lot of stress. And perhaps something to be mindful of concerning--or even be an important reason behind--autism therapy fatigue.
IACC & Vaccines; Scientists & the Public
Published July 13, 2009 @ 12:45AM PT
This Wednesday, the Interagency Autism Coordinating Committee---a federal committee that coordinates "all efforts" in the Department of Health and Human Services (HHS) concerning autism---is meeting in Washington, D.C. The agenda for this meeting:
- a joint meeting of the IACC and the National Vaccine Advisory Committee (NVAC) Vaccine Safety Working Group to discuss vaccine safety and autism - presentations on the NIH Autism Centers of Excellence and the National Database for Autism Research (NDAR)
- discussion of services-related activities
- analysis of the autism research portfolio
As evinced by the response to my most recent post on vaccines and autism, the first agenda item will most likely absorb a lot of attention and energy. The specific topic under discussion is to be "Feasibility and Design Issues Regarding Epidemiological Studies of Vaccinated, Unvaccinated and Alternatively Vaccinated Populations"---the sort of study that proponents of the notion that vaccines or something in vaccines might be "linked" to autism as a cause have long been calling for.
It's notable that the focus on this discussion item is "feasibility and design issues." There's been numerous calls by anti-vaccine/pro-vaccine safety advocates for such a study. Such advocates have asked, "What's so hard about doing such a study? Find a population of unvaccinated children, a population of vaccinated children, and compare the rates of autism---what's so hard about that?"
I'm not a scientist and, as noted, my educational background is in the humanities. So on the one hand, I very much see where the anti-vaccine/pro-vaccine safety advocates are coming from.
On the other hand, from what I've learned about designing and undertaking research studies, it's one thing to have an idea for a study, and another thing to execute it. What's under discussion is an epidemiological study that would involve studying the medical records of many, many children and a very large sample size of medical records at that. According to a 2008 survey from the Center for Disease Control and Prevention, most parents in the US have their children vaccinated, "with at least 90 percent coverage for all but one of the individual vaccines in the recommended series for young children." It's most likely that there'll be more children who have (1) been vaccinated and (2) have been diagnosed with autism, because there are more child who have been vaccinated than there are children who have not been.
But anyways. I'm glad that the IACC and the NVAC are discussing such a study, if only to put some of these variables out for consideration. Whatever the design or results of such a study, should the findings be further proof that there is no link between vaccines and autism (because there is no link), it's likely we'll see protests that something was done wrong, that the researchers had some kind of "bias," or some "moving of the goalposts" (as Orac at Respectful Insolence puts it), and further calls for "studies" and disputes about "the science."
The topic of vaccines and autism typifies the gap between scientists and public opinion noted in a report released last week by the Pew Research Center.
