The Hughes Brothers report these numbers with sadness.
One American child in sixty-eight is affected by autism, with boys included in that fraction at a rate five times that of girls.
New research suggests, however, the diagnostic methods currently recognized as best medical practice often overlook girls, a distressing thought meaning that even more young people may find themselves on the spectrum of autism disorder.
Three principal reasons for this newfound disparity
· Findings – from both behavioral analysis and preliminary neuroimaging – manifest themselves differently in girls, most specifically in that young females with autism are closer in their social skills to males developing typically.
· Almost all of the criteria for diagnosing autism have been built around boys, including behaviors that in girls might heretofore have been diagnosed as obsessive-compulsive disorder or attention-deficit/hyperactivity disorder or, even, anorexia.
· Until recently, prevailing clinical opinion held that, if autism were to manifest itself in girls, the symptoms would be far more severe than in boys, particularly in intellectual disability. Not necessarily so, the new research says.
Compensation and clinical bias, unintended, of course
Autism’s skewed gender ratio may arise, first of all, from girls ability to hide or to compensate somehow for the symptoms of ASD. The abilities in social situations cover for some of the underlying behavioral symptoms of the disorder. Further, ongoing research tells us that biological factors – girls and boys are indeed different – might prevent the development of the condition, beginning at birth.
The bias, based on all best thinking at the time, has historically called for more, and more serious, behavior problems or more troubles intellectually, or both, in girls before a diagnosis of autism might be made.
The unfortunate conclusion researchers are coming to, then: clinicians are missing many young females appearing on the less disabling end of the autism spectrum, what has traditionally been called Asperger’s syndrome.
“Restricted interests,” as an indicator of autism in girls
Tightly focused, repetitive all day long, and peculiarly personal, the intense fixation on a particular subject or objects can be a key indicator of autism at its less severe. (The Hughes Brothers have already reported on our little buddy Charley, up in Minneapolis, whose passion in life involves cassette tapes. No CDs. No vinyl, thank you very much. Just audio cassettes, the music thereon not much of a concern but, man oh man, the individual tape must, must, must be in its proper case.) Now, the studies referenced earlier reports that girls exhibit far fewer of these restricted interests. Could it be, however, that this differential might arise from the examples used in the diagnosis being more oriented toward boys. That is, the diagnostic factors might involve dinosaurs or toy trains far more than stereotypically female interests, dolls for instance, or pretty shoes. This weighted value of typically boyish interests contributes as well to the frequent failure of diagnosis of ASD in girls.
A nationwide, prestigiously academic effort in the study of women and girls with autism
The Hughes Brothers know of a major study of girls with autism, and adult women as well, being conducted in collaborative research at Harvard University, the University of California, Los Angeles, and the University of Washington. This study, a far-reaching and ongoing search for clinical information, will follow participants through their childhood and on to early adulthood. The researchers are spending time with, asking pointed questions of families of these girls, these women because they know firsthand the most problematic behaviors, the most troublesome symptoms of ASD. And the most helpful solutions thereto.
The study goes far beyond autism: brain scans, genetic testing and other such measures will tell us much about developmental differences in girls and boys attributable to autism, as opposed to gender. But also raising questions about whether autism affects sex differences in the brain and, ultimately how genetic and environmental factors come together in the production of gender-particular behaviors.
The Hughes Brothers have much more to say on the subject.
Please stand by.