|
|
|
|
What are Autism Spectrum Disorders?Autism is diagnosed on the basis of behaviour. This is because at this time there are no specific genetic or biological markers that accurately identify a person as being on the autism spectrum. There are three main categories of difficulties people on the spectrum have in common. These difficulties are:
Autism first manifests in childhood, with age of onset for a diagnosis being under the age of 3 years. This does not necessarily mean that a person is diagnosed before turning 3 years of age, only that symptoms were present at that developmental stage. Although not stated in the main diagnostic schedules, many clinicians use the term “Autism Spectrum Disorder” (ASD) to describe a continuum of related disorders, including autism, Asperger syndrome, and Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS). The categories within the autism spectrum are related to both severity and the presence or absence of some symptoms. Impairments in social interactionThe type of impairment in social interaction in ASD is varied. These can include marked problems with nonverbal behaviours, such as eye contact, facial expression, gestures, and body position, which are commonly used to regulate social interactions. It is often the case that people with an ASD do not develop relationships with children and adults from their peer groups at school and work. They may also feel no need to share personal experiences of achievement or enjoyment with others, and may also be unresponsive to social or emotional displays by others, especially those that are not immediately obvious. Impairments in communicationDelay in development of spoken language (including not developing language at all) is also a symptom of ASD. It is important to understand that language delay or absence is an indicator of autism only where a person does not try an alternative strategy to communicate actively, such as through gestures or mime. For people with an ASD who are able to speak, it is often the case that they do not initiate or sustain conversations. People with autism who are able to use language will often use words and phrases that are repetitive. They can also use language in a very formal way when communicating with familiar people, or adopt a style of speech that they maintain at all times, regardless of the listener. In addition, children with an ASD tend not to engage in the types of pretend play commonly observed in children at their developmental level. Restricted and/or repetitive patterns of behaviour, interests and activitiesSome people with an ASD show an intense interest in one type of activity. In these cases, the object of interest, for example trains and train schedules, consumes an unusually large amount of time or attention. People with autism often find it difficult to be socially flexible with regard to routines and rituals. Small changes to routine may cause these people significant distress, especially if specific rituals are associated with the disturbance. Repetitive mannerisms, such as hand flapping and finger flicking can be observed in those with an ASD, especially when they are feeling anxious. Another aspect of ASD is that some people with autism are preoccupied with parts of objects rather than objects themselves. An example of this is can be seen where a child with autism persistently spins one wheel of a toy car, when other children of that age are playing with the car as a toy vehicle. Other behaviours commonly observed in ASDAs well as the triad of symptoms outlined that are observed in ASD, many researchers and clinicians believe that other criteria are valid and important to consider when diagnosing ASD. Susan Mayes includes sensory disturbances in her diagnostic criteria, as well as fear of crowds, sleep disturbances, limited food preferences, and highly tolerance to pain while being sensitised to light touch. There is a significant body of evidence to suggest that people with ASD are more likely to demonstrate heightened response in all sensory domains, and this also is regarded as an important indicator of autism by Christopher Gillberg. It is also common to find motor clumsiness in people with ASD. Tony Attwood has suggested that these problems can affect gross motor skills, such as walking and balance, as well as fine motor skills such as handwriting and cutting with scissors. Motor problems can also affect timing and rhythm, as well as causing difficulties in imitating others as often occurs in social interaction. What is the difference between Autistic Disorder, Asperger's Disorder/Syndrome and PDD-NOS?Autism spectrum disorders are diagnosed on the basis of criteria set out in manuals and the research literature. The main sources of diagnostic criteria are the Diagnostic and Statistical Manual of Mental Disorders, currently in a revised fourth edition and commonly known as the DSM-IV (pronounced “D S M 4”), and the International Classification of Diseases and Health Related Problems, in its tenth revision and commonly known as the ICD-10 (pronounced “I C D 10”). Versions of the DSM are produced by the American Psychiatric Association, while the ICD is published by the World Health Organisation. It is more common for clinicians in Australia to use DSM-IV criteria when assessing children for ASD, but this is not universally the case. The DSM-IV includes a diagnostic category of ‘Autistic Disorder’ in the section titled Pervasive Developmental Disorders. The diagnostic criteria for the DSM-IV and the ICD-10 for autism are almost identical, although in the ICD-10 it is known as ‘Childhood Autism’. For a diagnosis of autism, at least two symptoms of impairment in social interaction, one symptom of impairment in communication, and one symptom of restricted and repetitive behaviour must be present. [Link to move to Diagnostic criteria page] The DSM-IV includes a diagnostic category of ‘Asperger’s Disorder’ in the section titled Pervasive Developmental Disorders. The diagnostic criteria for the DSM-IV and the ICD-10 for this condition are almost identical, although in the ICD-10 it is known as ‘Asperger’s Syndrome’. It is common in both the research literature and in clinical settings for the condition to be referred to as ‘Asperger syndrome’, as well as the previous names. For a DSM-IV diagnosis of Asperger’s Disorder, at least two symptoms of impairment in social interaction and one symptom of restricted and repetitive behaviour must be present. In addition, there must be no significant general delay in development of language, normal cognitive development, age-appropriate self-help skills, adaptive behaviour, and curiosity about the environment. There is a lot of debate as to whether Asperger syndrome should be a separate diagnostic category to autism, and this is discussed further below. The DSM-IV includes a diagnostic category of ‘Pervasive Developmental Disorder Not Otherwise Specified (Including Atypical Autism)’ in the section titled Pervasive Developmental Disorders. This diagnosis is used where there is a sever and pervasive impairment in one or more categories of the symptoms of autism, but where there are cases of late onset after 3 years of age, one or more diagnostic criteria are not met for Autistic Disorder or Asperger’s Disorder, or symptoms are present but not severe enough for a diagnosis of another ASD. Are Autistic Disorder and Asperger's Disorder/Syndrome really different?At this point in time, there does not seem to be a consensus regarding the distinction between Asperger disorder/syndrome and autistic disorder. There does seem to be agreement that people with Asperger disorder/syndrome, like those with autism, share difficulties in the three major areas mentioned above. There is less agreement about what distinguishes one diagnosis from the other. According to the definition used in the DSM-IV, in Asperger’s Disorder, there can be no delay in the development of language. In other words, although language is disordered, words, phrases, and sentences came in at the expected time. However, Tony Attwood, in his book, Asperger’s Syndrome: A Guide for Parents and Professionals, has a somewhat different view. He states that, “Research suggests almost 50 per cent of children with Asperger’s Syndrome are late in their development of speech, but they are usually talking fluently by the age of five.” Similarly, Peter Tanguey believes the definition of Asperger’s Disorder in the DSM-IV does not cover enough people, since many, if not most of these children had delays in language development. Another distinction has to do with cognition. In autism, there is an enormous range of intellectual functioning. In Asperger syndrome, cognition is normal, and often gifted in certain areas. Lastly, some clinicians believe that the difficulties with social relatedness are more severely impaired in autism than in Asperger syndrome. The latest published research by Patricia Howlin in the UK suggests that the diagnostic categories of autism and Asperger syndrome are so blurred by both researchers and clinicians that regarding them as separate conditions may be resulting in more confusion in diagnosis, rather than providing any assistance. In mid-2002, Bruce Tonge from Monash University in Victoria stated in the Medical Journal of Australia that, “To avoid confusion, the term ‘autistic spectrum disorders’ should only be used as the collective term for a group of defined disorders”. In recent times, even Lorna Wing, the researcher responsible for bring the work of Hans Asperger to light in the English-speaking world in the early 1980s, has stated that she never intended for Asperger syndrome to be regarded as a separate condition to autism, and that it was only meant to be a guide to the variability that could be observed in people on the autism spectrum. Larry Cashion for A4 If you wish to download the above document please click the link below. |
|
Copyright © 2003-2007 A4 - Autism
Aspergers Advocacy Australia
|
