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PART 1
Diagnosis and Characteristics
1.What are Autism Spectrum Disorders (ASD)?
2.Is there a difference between High Functioning Autism and Aspergerās Syndrome?
3.Are there medical tests to diagnose ASD?
4.How is ASD diagnosed?
5.What tests are used to diagnose ASD?
6.Who can diagnose ASD?
7.What are the common characteristics associated with a diagnosis of ASD?
8.At what age can ASD be diagnosed?
9.Are there gender differences in ASD?
10.How often does ASD occur? What is its prevalence?
11.Is there an ASD epidemic?
12.What conditions typically co-exist with ASD?
13.Can you cure ASD?
14.Are children with ASD mentally retarded?
15.What are the typical speech and language problems associated with ASD?
16.Are savant skills common in ASD?
17.What is Theory of Mind Deficit or Mindblindness?
18.What are Executive Function Deficits?
19.What are Central Coherence Deficits?
20.What are Nonverbal Learning Disabilities (NLD)?
21.What is Hyperlexia?
22.What is Pathological Demand Avoidance Syndrome (PDA)?
1What are Autism Spectrum Disorders (ASD)?
Autism Spectrum Disorders (ASD) is a term used to describe a category of conditions also referred to as Pervasive Developmental Disorders (PDD). PDD includes: Autism or Autistic Disorder, Rettās Disorder, Childhood Disintegrative Disorder, Aspergerās Disorder, and Pervasive Developmental DisorderāNot Otherwise Specified (PDD-NOS) which includes Atypical Autism. These disorders affect three primary areas of development: communication (verbal and nonverbal), social interaction and repetitive patterns of behavior, interest and activities. They have been grouped together under the single heading Pervasive Developmental Disorders in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), the American Psychiatric Associationās ābibleā for diagnosing mental conditions. Another such manual for diagnosis used internationally, but less frequently in the United States, is the International Classification of Disease, 10th edition (ICD-10).
Autism or Autistic Disorder typically refers to the traditional or classical forms of what psychiatrist Leo Kanner identified in 1943 and labeled as āearly infantile autism.ā According to the DSM-IV, a person must have 6 of the possible 12 diagnostic criteria in order to be given the diagnosis of Autism. At least two must be in the area of social impairments and at least one each in the areas of communication impairments and behavior/interests and activities. (See Appendix A for diagnostic criteria.) Most individuals with Autism have Mental Retardation.
Aspergerās Disorder, also called Aspergerās Syndrome, was initially described by Austrian physician Hans Asperger in Vienna in 1944. He identified children who had some similarities to those Kanner had described, but who also had some differences. Most notably these were the awkward use of language, the lack of humor and the strange use of nonverbal communication including eye contact, gestures, posture, and inflection patterns (prosody). For reasons that are not known, Aspergerās work was not widely publicized in English-speaking countries until Lorna Wing wrote about his work in the 1980s. It was not until the mid 1990s that the label was included in the diagnostic manuals (DSM-IV and ICD-10). There are eight diagnostic criteria for Aspergerās Syndrome. Of these, a person must have at least two impairments in social interaction and at least one in behavior/interest and activities. Unlike a diagnosis of Autism, in Aspergerās Syndrome, current diagnostic criteria indicate there are no clinical significant delays in either language or cognitive development (see Appendix B for diagnostic criteria for Aspergerās Syndrome).
Rettās Disorder (or Rett Syndrome) is characterized by the loss of previously acquired skills and the development of a frequent hand-wringing behavior. There is a deceleration of head growth between 5 and 48 months, severely impaired expressive and receptive language with severe psychomotor retardation, and a loss of social engagement, which often develops again after the preschool years. Rett Syndrome is usually associated with severe or profound Mental Retardation. Unlike the other ASDs, Rett Syndrome primarily affects females and a specific gene mutation (MECP2) has been associated with the diagnosis. Not all individuals with Rett Syndrome have an identifiable mutation in MECP2 and not all individuals with a MECP2 mutation have Rett Syndrome. (See Appendix C for a description of Rett Syndrome diagnostic criteria.)
Childhood Disintegrative Disorder is characterized by a period of normal development for at least the first two years and then a loss of previously acquired skills before the age of ten. The loss of skills occurs in at least two of the following areas: language, social, adaptive skills, bowel or bladder control, play and motor skills (see Appendix D for diagnostic criteria for Childhood Disintegrative Disorder).
Pervasive Developmental DisorderāNot Otherwise Specified (PDD-NOS) is the ASD label used when a person exhibits impairments in the social interaction, communication (verbal and nonverbal) and stereotyped behaviors, interests and activities but they do not meet the criteria set forth in the diagnosis of Autism or the other PDD labels. Essentially, PDD-NOS is used for a person whose behaviors and abilities are described as āAutistic-likeā but do not meet enough (6 out of the 12 criteria) or are not severe or significant enough to warrant the diagnosis of Autism.
Many people believe that the term PDD is too general and has not adequately addressed the diversity of conditions associated with this label. With the evolution of newer classification systems, such as multi-system neurological disorders and regulatory disorders, many of the current terms may eventually be replaced.
2Is there a difference between High Functioning Autism and Aspergerās Syndrome?
Yes and no depending upon who you ask. Even the term āHigh Functioningā Autism is somewhat ambiguous since it refers to an individual who has more functional skills than another individual diagnosed with ājustā Autism. There is agreement that Autism runs on a continuum from mild to severe, but there is no clear delineation between a mildly impaired or high
3Are there medical tests to diagnose ASD?
No. There are now many new studies looking at ways to diagnose ASD medically, but currently there are no medical tests, no genetic markers, no blood tests or brain scans that can diagnose ASD.
Medical tests are often ordered when a person is being evaluated for ASD, but this is to either rule in or out other medical conditions rather than confirm a diagnosis of ASD. Some of the tests which a physician may order include:
ā¢a hearing test which may include an audiogram, tympanogram and brain stem auditory evoked response test (BAER) which are used to determine whether there is a hearing impairment
ā¢chromosome or DNA testing to consider the diagnosis of Fragile X Syndrome or other chromosomal or gene abnormalities
ā¢chemical and metabolic studies to look at various conditions for which special diets may be warranted
ā¢brain scans (e.g., CT scan, MRI) to look for neurological conditions, tumors, or to rule out Tuberous Sclerosis
ā¢EEGs which measure brain waves to consider a seizure disorder or Landau-Kleffner Syndrome.
There is promising new research now being conducted which may help in the identification and subsequent prevention and treatment of ASD. Studies funded by a coordinated group of organizations led by head researcher Dr Karin Nelson1 of the National Institute of Neurological Disorders and Stroke (NINDS) is identifying brain proteins which are crucial in the development of the nervous system and which may help to identify Autism and Mental Retardation at birth.
From the Human Genome Project, we have learned that there are susceptible spots on some chromosomes (2, 6, 7, 15, 16, 17), but at this time they do not predict or confirm a diagnosis of ASD.
The only way to diagnose ASD at present is with a combination of observation and questions, ideally from a multidisciplinary team of professionals with experience in ASD (as described in the next question).
4How is ASD diagnosed?
A diagnosis of ASD is made from a comprehensive assessment of both historical information and current abilities. Areas addressed in a comprehensive assessment often require a multidisciplinary team of professionals who can each address specific aspects of development. Who does such an assessment is addressed in question 6 in this section.
As indicated previously, there are currently no medical tests available which can diagnose ASD. The diagnosis is made from a combination of observations, questionnaires and standardized tests (listed in question 5 and further described in Appendix E), which measure various aspects of behavior and ability in several different areas of development. In order to make a diagnosis of ASD, a person must meet certain criteria that are listed in the diagnostic manuals referred to as DSM-IV-R or ICD-10. These manuals are used by health professionals to diagnose most conditions and the criteria for diagnosing ASD are listed in Appendices AāD.
Unlike a blood test in which you can objectively identify something that is, or is not, present in the blood, observations and questionnaires are a far more subjective means of assessment. That is one reason why individuals may have difficulty obtaining an accurate diagnosis. Asking a parent about a childās behavior is not exactly āscientific.ā Deciding whether a childās behavior is ānormalā or āaverageā for their age or āunusualā requires sophisticated observational skills and references for what is ānormalā or āaverageā or āunusual.ā In addition, parents are often asked to report on how their child behaved many years earlier, and this can be quite difficult since recall can be distorted by the passage of time.
5What tests are used to diagnose ASD?
There are a number of standardized tests and questionnaires used by various professionals to assist in the diagnosis of ASD. In order to determine whether an individual meets the criteria of DS...
