Friday, April 28, 2006

What science tells us about treating autism and ADHD

Alas, not very much.
John Hawks Anthropology Weblog : Evidence-based medicine and education

...At the Cambridge conference, prominent neuroscientists working in areas such as literacy, numeracy, IQ, learning, social cognition and ADHD spoke directly to teachers about the scientific evidence being gathered in scientists' laboratories. The teachers were amazed by how little was known. Although there was enthusiasm for and appreciation of getting first-hand information, this was coupled with frustration at hearing that many of the brain-based programmes currently in schools had no scientific basis. The frustration arose because the neuroscientists were not telling the teachers 'what works instead'. One delegate said that the conference "Left teachers feeling [that] they had lots stripped away from them and nothing put in [its] place".
Years ago I reviewed the ADHD literature, including some state-of-the-art reviews. Bottom line: we knew very little. Things aren't much better.

It's just as bad in autism. We don't even know what we're studying -- the terms "autism" and "ADHD" and the associated DSM-IV criteria may confuse more than they help. It's very hard to study something you can't even properly name.

There's a lot of great science happening now. In twenty years we may have new words, new diagnostic tests, maybe even evidence-based therapy. For now we're walking in very dim light. Recently I had a psychiatrist suggest the benefits of omega fatty acides in autism -- only to admit that the first trial that might give us a hint of a clue is barely starting.

Dim light indeed! Parents and therapists have to work with the data we have, but, for now, we must treat each intervention as an experiment that should be monitored. Continue it it helps, stop if it doesn't, try to measure outcomes objectively.

Most of all, clinicians should be humble. We don't really know what's going on and what helps or hurts.

PS. There are some topics, however, where there is decent evidence of a "dead end". It's really time to put the vaccine preservative and dental mercury stuff way in back of the back burner. There are so many better places to put resources now.

Wednesday, April 19, 2006

Wednesday, April 12, 2006

Autism: probably not increasing - whatever it is

A research paper claims that the apparent increase in autism prevalence is primarily the reclassification of mental retardation as autism...
Respectful Insolence: Evidence against an "autism epidemic"

... Shattuck analyzes special education figures that are being used to bolster claims of an autism "epidemic" and finds them wanting. In essence, diagnostic substitution can explain nearly all of the apparent increase of autism as recorded by the number of children receiving special education services. What that means is that children that would have been diagnosed with something else 15-20 years ago are now being diagnosed with autism. Dr. Shattuck starts with an example from a different condition, mental retardation as one of his reasons for suspecting diagnostic substitution as a cause of the perceived "epidemic":

...Second, prior research has established a precedent of diagnostic substitution in special education enrollment. From 1976 to 1992 the number of children in the mental retardation (MR) category decreased by 41%, whereas the number in the learning disabilities (LD) category increased 198%. There is considerable evidence that suggests this was because of a growing likelihood that schools would use the LD label for children with mild MR, presumably because a label of LD was increasingly seen as carrying less stigma than MR. Finally, a recent epidemiological study depicted a downward deflection in the incidence trend of other developmental disorders just as the trend for autism made a sharp upturn in the early 1990s, again suggesting the possibility of diagnostic substitution.
RI goes on to quote from an editorial arguing that the data is not sufficient to rule out some increase, even if it is not as enormous as initially thought.

I tend to believe the increase is relatively small, and perhaps due to the "silicon valley effect" (mating engineers). I have personal knowledge of two children who have both "educational" and "clinical" (different worlds) diagnoses of autism spectrum disorder. They are remarkably different people with very different IQs and abilities. In some ways they are almost perfect opposites, though they share a few common traits.

This is a superb mess. Much of its driven by an astoundingly boneheaded decision; "mental retardation" does not quality for educational services in most states, "learning disability" or "autism" do. I think the reasoning is supposed to be that "MR" can't be helped by special services, but an assymetric defect or autism can. Not surprisingly psychologists, physicians, teachers, and parents serve the needs of children best by conspiring to make the diagnosis of "mental retardation" relatively rare. Duh.

Other than the "mental retardation services" debacle, the autism classification confusion is perpetuated by our almost complete lack of understanding of what's happening, why it happens, and how it happens in the brains of these children and adults. It's very hard to classify something you truly don't understand. "Dropsy" in the 19th century became everything from venous insufficiency to renal failure to heart failure in the 20th century.

We're gradually moving to an anatomic-functional-genetic classification of brain development disorders. With luck both "autism" and "schizophrenia" will join "dropsy" in the garbage heap of abandoned ontologies. One day we'll be able to make meaningful assignments of individual brains to useful classifications, and then the real research will begin.

Sunday, April 09, 2006

Autism: a deeper understanding of the "face" problem

It's not a surprising breakthrough, but it's an interesting study that is consistent with an emerging picture. They studied ASD persons with above average IQ. I know someone like that.
BBC NEWS | Health | Weak brain links 'explain autism'

...Dr Geoff Bird, at the UCL Institute of Cognitive Neuroscience, who led the research, said: 'The standard view of social problems in ASD is that there is a problem in the part of the brain that processes faces.

'Our research suggests that this is not the real problem - it seems to be that paying attention to faces doesn't lead to the normal increase in brain activity.

'This is because the face-processing areas of the brain are not well connected to those parts of the brain that control attention - such as the frontal and parietal regions.
So persons with autism can indeed process facial data well, but the data doesn't connect up with anything. It gets handled like any other visual input, it doesn't benefit from special networks that facilitate social interaction. Presumably those networks involve "mirror neurons". My personal wild guess is that the motor neuron network is sacrificed during early development to compensate for other brain injuries.

In time we may understand how to create electronic aides, "cognitive prostheses", to compensate for some of this ...

Tuesday, April 04, 2006

Siblings of disabled children

The NYT has a brief review on the experiences of siblings of disabled children. There's nothing new, but it's noteworthy that there's more discussion. Some do well with increased responsibilities, others are burdened. There were no evidence-based recommendations on how to mitigate harm done to siblings.