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There is considerable disagreement over the exact nature of autism. It is generally believed to be a spectrum or cluster of physical, mental and emotional conditions of varying severity, none of which are well understood. Although some have claimed that there are specific physical conditions comorbid to autism spectrum disorders, not all people diagnosed with autism spectrum disorders experience these, and the diagnostic criteria, as of 2006, are still limited to psychiatric evaluation methods.
The cause(s) of autism and the spectrum of pervasive developmental disorders (PDDs) are as yet unknown, as are the prognoses, or best treatment options. There is, however, widespread agreement that early diagnosis and intervention can often make a significant difference for the long-term prospects of a person with autism because the human mind and nervous system are more plastic at a younger age; therefore, research for possible therapies and treatments is often focused toward children who have been diagnosed early with a spectrum disorder. However, many adults on the autistic spectrum, as well as other interested parties, believe that this emphasis on the problems facing children has resulted in limited research and treatment options for adults with autism.
Today's medical community considers autism to be essentially incurable, or at least to have life-long effects. Meanwhile, judging by the plethora of material on the Internet and elsewhere, many autistic spectrum adults and neurotypical (non-autistic) allies in the autism rights movement do not consider autism to be a disorder, but simply a different way of perceiving and behaving. These people believe that at least some of the difficulties encoutered by people with autism may result from prejudice and lack of accommodation from society.
With knowledge being so limited and scientific progress so slow, nearly all conjectures about autism are hotly debated. Parents of autistic kids face a bewildering set of choices and attendant uncertainty about the merits of various diagnoses, prognoses, and alleged 'cures' and treatments. Some of these controversies are described below.
The usefulness and accuracy of autism as a diagnosis
The 1994 DSM-IV criteria for the diagnosis of autism are the result of several revisions, and consequently the psychiatric community is divided as to whether the condition should be ordered by severity along a spectrum or categorised into multiple distinct disorders that have similar symptoms. This division is exacerbated by the wide range of conditions comorbid to autism spectrum disorders. Research and clinical experience suggests that, while autism may appear to manifest itself as a psychiatric disorder, its underlying causes are neurological. PDD has emerged as an overarching descriptive term for the cluster of disorders that includes autism.
A diagnosis of autism is complicated by the fact that there is no definitive test for autism due to the significant variance in the severity of symptomology among people with autistic traits. Those with Asperger syndrome may be highly functional cognitively but lack 'social' skills, whereas others with 'profound autism' may be non-verbal and deficient in elementary skills. Some autistic people are 'mentally retarded', having low IQs (Intelligence Quotients), while others have average or above average intelligence. A minority of people with autism even have narrow, but exceptional autistic savant abilities.
This is not just an academic issue - treatment strategies and choices are based on definitions of what needs to be changed. Different treatment approaches have had widely divergent outcomes depending on each specific person. For example, some parents claim their children recovered with only behavioral approaches, some credit biomedical intervention as the best method for improvement, and others report little or no progress after trying many different approaches. Occasionally, parents claim their autistic children have simply "grown out of it".
There are also those (primarily the autistics themselves) who reject the premise that autism is necessarily a disorder that should be cured. In their view, a diagnosis can sometimes result from a judgment of non-conformity that is followed by efforts to correct what are essentially personality traits.
Asperger's Syndrome and autism
Currently, Asperger's syndrome is classified as a separate diagnosis from autism in the DSM-IV, but it is still considered an autism spectrum disorder. The primary distinction between the definitions of autism and Asperger's Syndrome in the DSM-IV is that autism involves a speech delay and Asperger's does not. Many people believe autism and Asperger's syndrome should not be given separate labels in the DSM-IV because they believe that differences in language acquisition are not significant enough to separate the disorders or that autism and Asperger's have no definitive differences. It is also unclear whether a child with high-functioning autism who learns to speak should have their diagnosis changed to that of Asperger's Syndrome.
'Autistic' vs. 'Has autism'
Many autistics who express their views on the Internet have stated their preference for the word autistic to be used as both an adjective and a noun; they dislike the politically correct person-first terminology. Some persons with Asperger's syndrome prefer to be called Aspergerian or aspie.
Person-first terminology is preferred by many with medical conditions, such as AIDS or epilepsy, where it may serve to remove some of the stigma of these illnesses. Many in the autistic community feel that to use person-first language conveys the impression that autism is another such disease, something that can and should be cured. These autistics feel that autism is an integral part of their identity, that the person and the autism cannot be separated, and that proposing the removal of autism is akin to proposing death for them.
As with other such arguments involving the autism rights movement, many parents of autistic children disagree with the position of the autistic self-advocates. They contend that autism is an illness, that autism is not part of the person, and should be removed or cured.
Person-first terminology remains the preferred form in most clinical literature about autism.
Epidemiology of autism
- For more details on this topic, see frequency of autism.
There is uncertainty and controversy over whether the incidence of autism is actually increasing or if there simply is an increase in the number of reported cases. Some argue that if the incidence is rising, then environmental factors play a greater role; if it is simply being reported more often, genetics deserves more attention. One theory, particularly associated with Simon Baron-Cohen, suggests that increased social mobility and assortative mating may lead to the genetic amplification of autistic traits. Natural selection of traits useful in the information age has also been noted.
Anecdotal reports from school districts and physicians lend support to the impression that the incidence is rising, and some studies appear to support this as well. Some believe the incidence has risen markedly in the last few years, from about one in 5000 to estimates ranging between one in 400 or even as high as one in 166, which may indicate a major societal problem. In the United States, Centers for Disease Control (CDC) have vacillated between the latter two figures. In January of 2004 the CDC sent out an autism alarm to all pediatricians stating that they believed that 1 in 166 children had an autism spectrum disorder and as common as one in six now suffered from a neurodevelopmental or behavioral disorder. (Others have quoted these figures as high as 1 in 40 for autism and one in three for the neurodevelopmental or behavioral disorders.)
Others point out that several factors are likely to cause increased reporting. First, some say that the broadening definition of autism, which began most markedly with revised classifications in DSM-III-R in 1987 and the greater availability of services for autistic individuals, creates an incentive to be inclusive in the diagnosis. Second, the last few decades have seen a greater awareness of autistic traits among pediatricians and other medical specialists, and it is surmised that some children who were previously diagnosed as retarded, or as having a psychotic disorder are now diagnosed as autistic or having PDD. (Autism was once believed to be a type of childhood schizophrenia.)
It will take time to resolve these diagnostic prevalence issues. As previously mentioned, there is no definitive, standardized way to diagnose autism, whether in past, present, or future incidences. There are important implications from this controversy because the answer will guide both the allocation and magnitude of research, legal action, and therapy in the future.
Genetics and autism
- For more details on this topic, see Heritability of autism.
There is evidence that autism has a genetic component, and ongoing research focuses on finding the biomarkers that determine autistic phenotypes. However, there is significant disagreement as to whether genes contribute to a vulnerability to environmental triggers or have another role in the etiology of autism.
There is a trend in research towards viewing genetics as an underlying factor. However, most autistic children have apparently neurotypical parents, which suggests that a single gene is not likely the cause. The spectrum of autistic disorders is notable for its significant gender disparity, with the incidence of autism in males greatly exceeding the incidence in females. A 1994 study estimated the ratio at three males to one female, while a 1982 Japanese study indicated a ratio of nine to one. Several studies on human and animal tissue suggest that testosterone potentiates the toxic effects of mercury, hence the gender disparity has been suggested to add credence to the theory that mercury plays a role in the etiology of autism. There are some, however, who speculate that autism occurs equally in both sexes, and that males are simply more likely to be diagnosed because of differences in childhood socialization.
Scientists have recently (July 2005) shown that variations in the gene for protein kinase C beta 1 (PRKCB1), a protein with an important role in brain function, are strongly associated with autism. This exciting find suggests some answers to a number of previous, but unexplained, observations about autism and provides the potential for a mechanistic explanation for some of the characteristics of the condition.
Implications of genetic testing
If and when genetic testing for autism becomes available, it is anticipated that many women pregnant with an autistic child will decide to abort the pregnancy. There is some precedent from Down's Syndrome which points in this direction. Autism rights advocates believe this will be akin to genocide. Furthermore, the impact of such an event on the human species as a whole could be very significant. Assuming that it is true that people such as Albert Einstein and Isaac Newton were autistic, as some speculate, common pro-life arguments such as "What if the next Einstein were to be aborted?" would potentially be more biologically persuasive.
Vaccines and autism
In the late 1990s, controversial theories arose that linked childhood vaccinations to autism.
- Main article: Vaccine controversy
MMR triple vaccine
- Main article: MMR vaccine
Intelligence and autism
- For more details on this topic, see Intelligence tests and autism.
Until recently, a large proportion of children diagnosed as having autism were also believed to have mental retardation. The term 'mentally retarded' itself is debatable because this determination is based on IQ testing, which has its own set of controversies and detractors. A more accurate description would be to say that children who are diagnosed autistic may also have low IQ scores. However, this view is inconsistent with other findings, particularly the increased incidence of 'high-functioning' autism and the recognition of Asperger's syndrome as being part of the autism spectrum.
Autistic persons who have normal or high intelligence are often not diagnosed with autism, so the average IQ of the autistic community as a whole cannot be determined. Furthermore, anecdotal accounts of autistic children whose IQ scores have increased dozens of points over a relatively short period of time are not uncommon. It has been suggested that these increases do not correspond to an increase in actual intelligence, however; perhaps, as with neurotypical children, children with autism may simply get better at taking IQ tests (the so-called practice effect).
Characteristics observed by some studies as being associated with gifted children at least appear to be analogous to those of autistic children:
- Some studies suggest that gifted children are more than twice as introverted as their peers.
- Gifted children have been characterized as having obsessive interests, preferring to play alone, and enjoying solitude. They are also said to have prodigious memories and show intense reactions to noise, pain and frustration.
- According to some reports, gifted children have a higher-than-average propensity to allergies
An alternative view is that autism and intelligence are unrelated; all levels of intelligence have been observed in those with autism. According to this view, those with autism and low intelligence would be more likely to be recognized and diagnosed, and those with normal to high intelligence might be better able to articulate their experiences (either verbally or through writing) and would be labeled as high-functioning regardless of their other neurological deficits.
Prognosis for autistic children
Children who are diagnosed with autism face a great range of outcomes. Some are reported to have learned speech and/or writing, self-care, and social skills on their own. Others experience an apparently miraculous "recovery" and begin behaving in a way that is generally indistinguishable from the way neurotypical children behave, either for no apparent reason or from a few simple alterations in diet. Some become mainstreamed after years of hard work and intensive training. Some develop slowly, but never lose their diagnoses. There are a few who never move beyond a level of functioning that society perceives as 'low', yet others are fairly typical during childhood and report becoming "more autistic" in adulthood.
It seems paradoxical that while some people see early intervention as crucial for autism, the prognosis is also most uncertain the younger the child is. An idiosyncratic development path may be confused with a more severe disorder, and the child may 'catch up' on his/her own. Research indicates that the human mind and nervous system remains plastic for longer than originally thought, and people with autism, like those with learning disabilities, have been known to cognitively develop throughout their lives.
There is broad consensus in the medical community to the effect that autistic behaviors can be improved either through training or medical / educational interventions, though there is wide disagreement on what the right kinds of treatment are and what the appropriate objectives should be.
- List of autism-related topics
- Autism rights movement
- Aspies For Freedom
- Autistic culture
- Chelation therapy
- Generation Rescue
- Mark Geier
- Richard Deth
Pervasive developmental disorders / Autism spectrum
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