Misplaced Pages

Revision as of 17:58, 27 August 2007

The article's lead section may need to be rewritten. Please help improve the lead and read the lead layout guide. (Learn how and when to remove this message)

Asperger syndrome
Specialty	Psychiatry

Asperger syndrome (also referred to as Asperger's syndrome, Asperger's disorder, Asperger's, or AS) is a condition on the autistic spectrum. Like other autistic spectrum disorders (ASDs), Asperger's includes "restrictive, repetitive, and stereotyped patterns of behavior, interests, and activities." However, Asperger's differs from 'classic' autism in that there is no significant delay in non-social aspects of intellectual development. AS can have both positive and negative effects on an individual's life.

Asperger syndrome was named in honor of Hans Asperger, an Austrian psychiatrist and pediatrician who in 1944 decribed children in his practice who appeared to have normal intelligence but lacked nonverbal communication skills, failed to demonstrate empathy with their peers, and were physically clumsy; the term "Asperger's syndrome" was popularized in the English-speaking world by researcher Lorna Wing, who used the eponym in a 1981 paper. In 1994, AS was recognized in the Diagnostic and Statistical Manual of Mental Disorders (DSM) as Asperger's Disorder.

AS does not always affect people in the same way, but individuals tend to have aspects in common, such as a tendency to focus intensely on areas of interest, hyposensitivity or hypersensitivity to certain stimuli and sensory integration problems, self-stimulating ('stimming') behaviors such as rocking back and forth, and difficulty interpreting facial expressions and other social cues.

Some clinicians deny that AS is differentiated from other autistic spectrum disorders and indicate that a "DSM-IV diagnosis of Asperger's disorder is unlikely or impossible". Instead they refer to Asperger's as HFA, or treat the diagnoses interchangeably, arguing that language delay is a difference in degree and not kind. Less than two decades after the widespread introduction of AS to English-speaking audiences, questions remain concerning many aspects of AS: the diagnostic validity of Asperger syndrome is tentative, there is little consensus among clinical researchers about the usage of the term "Asperger's syndrome", and there are questions about the empirical validation of the DSM-IV and ICD-10 criteria.

Classification

Asperger syndrome is one of five pervasive developmental disorders (PDD), and is characterized by deficiencies in social interaction and normal to above normal intelligence, undelayed language development, and repetitive or restrictive patterns of thought and behavior. The four related disorders or conditions are autism, Rett syndrome, childhood disintegrative disorder, and PDD-NOS (pervasive developmental disorder not otherwise specified).

There is significant debate over the difference between AS and high-functioning autism (HFA) and whether they are separate and distinct disorders. While HFA has no standardized definition, and AS has several distinct definitions, diagnosticians and other clinicians often distinguish the two according to speech development or otherwise concider it significant. However, objective tests have yet to demonstrate the validity of this position, and at least one diagnostic guide takes the position that delayed speech may be a sign of AS. The diagnoses of AS or HFA are used interchangeably; the same child can receive different diagnoses, depending on the screening tool the doctor uses. Some researchers argue that there should be no boundary between high-functioning autism and AS, and that the fact that some people do not start to produce speech until a later age is no reason to divide the two groups, since they are identical in the way they need to be treated. In some countries, diagnoses may be influenced by non-technical issues, such as availability of government benefits for one condition but not the other; clinicians may diagnose autism rather than the more correct Asperger's if that helps a child receive classroom support, government funding or services covered by insurance.

Canadian PDD researcher Peter Szatmari says that the current classification of the pervasive developmental disorders is unsatisfying to many parents, clinicians, and researchers, and may not reflect the true nature of the conditions. The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) and World Health Organization ICD-10 focus on the idea that discrete biological entities exist within PDD, which leads to a preoccupation with searching for cross-sectional differences between PDD subtypes rather than recognition of the conditions as distinct points on a spectrum, a strategy which has not been very useful in classification or in clinical practice.

Characteristics

This article may need to be rewritten to comply with Misplaced Pages's quality standards. You can help. The talk page may contain suggestions. (August 2007)

Like autism, AS is characterized in the DSM-IV by impairments in social interaction and restricted interests and behaviors; however, it differs from autism in that those with AS lack clinically significant delay in spoken or receptive language, cognitive development, self-help skills, and curiosity about their environment. Intense preoccupation with a narrow subject, one-sided verbosity, restricted prosody and intonation, and motor clumsiness are typical of the condition, but are not required for a DSM-IV diagnosis; these features are included in other diagnostic schemes (see Diagnosis). Experienced clinicians use characteristics beyond the diagnostic criteria to distinguish between AS and HFA.

Describing the social interaction of individuals with AS, Harvard Medical School's Baskin, Sperber and Price have written that "the lack of empathy demonstrated by AS patients is possibly the most dysfunctional aspect of the syndrome". With respect to the restricted interests of those with AS, "one of the most striking features of individuals with AS is their passionate pursuit of specific areas of interest" (McPartland and Klin of the Yale Child Study Center). The DSM-IV does not specify language delays, but clinicians acknowledge abnormalities in speech and communication. Although individuals with AS "have considerable verbal ability they fail to utilize language appropriately in social interactions" (UCLA's Kasari and Rotheram-Fuller). Klin has written that "significant abnormalities of speech are not typical of individuals with AS", but "aspects of these individuals' communication patterns" are of clinical interest.

Social interaction

The unwritten rules of social behavior are said to mystify many with AS and have been termed the hidden curriculum. People with AS must learn these social skills intellectually through seemingly contrived logic rather than intuitively through normal emotional interaction.

Non-autistics are able to gather information about other people's cognitive and emotional states based on clues gleaned from the environment and other people's facial expression and body language, but, in this respect, some people with AS are impaired; this is sometimes called mind-blindness. People with mind-blindness are frequently unable to interpret or understand the desires or intentions of others and thereby are unable to predict what to expect of others or what others may expect of them. This sometimes leads to social awkwardness and inappropriate behavior.

The concrete nature of emotional attachment for people with AS (for example, attachment to objects other than people) often seems curious or can even be a cause of concern to people who do not share their perspective. However, failing to convey feelings of affection in a way that others understand does not necessarily mean that no affection is felt. Understanding this can lead partners or caregivers to feel less rejected and to be more understanding. Increased understanding can also come from learning about AS and any comorbid disorders. Sometimes, the opposite problem occurs: the person with AS is unusually affectionate to significant others; and misses or misinterprets signals from the other partner, causing the partner stress.

Repetitive behaviors and restricted interests

AS in children can involve an intense and obsessive level of focus on things of interest, many of which are those of neurotypical children. The difference in children with AS is the unusual intensity of the interest.

Sometimes these interests are lifelong; in other cases, they change at unpredictable intervals. In either case, there are normally only one or two interests at any given time. The interests are often linked in some way that is logical only to the AS individual. In pursuit of these interests, people with AS often manifest sophisticated reasoning, an almost obsessive focus, and a good memory for trivial facts (occasionally even eidetic memory).

Some clinicians do not entirely agree with this description. For example, Wing and Gillberg both argue that, in children with AS, these areas of intense interest typically involve more rote memorization than real understanding, despite occasional appearances to the contrary. Such a limitation is an artifact of the diagnostic criteria, even under Gillberg's criteria, however.

People with AS may have little patience for things outside these narrow interests. In school, they may be perceived as highly intelligent underachievers or overachievers, clearly capable of outperforming their peers in their field of interest, yet persistently unmotivated to do regular homework assignments (sometimes even in their areas of interest). Others may be hypermotivated to outperform peers in school. Symptoms may be seen by obsessional absorption with inanimate objects, such as watches and clocks; or a predominant interest in systematic things like numbers, indices, telephone directories, encyclopedias, dictionaries, or measuring scales. The combination of social problems and intense interests can lead to unusual behavior, such as greeting a stranger by launching into a lengthy monologue about a special interest rather than introducing oneself in the socially accepted way. However, in many cases adults can outgrow this impatience and lack of motivation and develop more tolerance to new activities and meeting new people.

Speech and language

People with AS typically have a highly pedantic way of speaking, using a far more formal language register than appropriate for a context. A five-year-old child with this condition may regularly speak in language that could easily have come from a university textbook, especially concerning his or her special area of interest.

Literal interpretation is another common, but not universal, hallmark of this condition. Attwood gives the example of a girl with AS who answered the telephone one day and was asked, "Is Paul there?" Although the Paul in question was in the house, he was not in the room with her, so after looking around to ascertain this, she simply said "no" and hung up. The person on the other end had to call back and explain to her that he meant for her to find him and get him to pick up the telephone.

Individuals with AS may use words idiosyncratically, including new coinages and unusual juxtapositions. This can develop into a rare gift for humor (especially puns, word play, doggerel and satire). A potential source of humor is the eventual realization that their literal interpretations can be used to amuse others. Some are so proficient at written language as to qualify as hyperlexic. Tony Attwood refers to a particular child's skill at inventing expressions, for example, "tidying down" (the opposite of tidying up) or "broken" (when referring to a baby brother who cannot walk or talk).

Children with AS may show advanced abilities for their age in language, reading, mathematics, spatial skills, or music, sometimes into the 'gifted' range, but these talents may be counterbalanced by appreciable delays in the development of other cognitive functions. Some other typical behaviors are echolalia, the repetition or echoing of verbal utterances made by another person, and palilalia, the repetition of one's own words.

A 2003 study investigated the written language of children and youth with AS. They were compared with neurotypical peers in a standardized test of written language skills and legibility of handwriting. In written language skills, no significant differences were found between standardized scores of both groups; however, in hand-writing skills, the AS participants produced significantly fewer legible letters and words than the neurotypical group. Another analysis of written samples of text, found that people with AS produce a similar quantity of text to their neurotypical peers, but have difficulty in producing writing of quality.

Other

Those affected by AS may show a range of other sensory, developmental, and physiological anomalies. Children with AS may evidence a slight delay in the development of fine motor skills. In some cases, people with AS may have an odd way of walking, and may display compulsive finger, hand, arm or leg movements, including tics and stims.

In general, orderly things appeal to people with AS. Some researchers mention the imposition of rigid routines (on themselves and/or others) as a criterion for diagnosing this condition. It appears that changes to their routines cause inordinate levels of anxiety for some people with this condition.

Some people with AS experience varying degrees of sensory overload and are extremely sensitive to touch, smells, sounds, tastes, and sights. They may prefer soft clothing, familiar scents, or certain foods. Some may even be pathologically sensitive to loud noises (as some people with AS have hyperacusis), strong smells, or dislike being touched; for example, certain children with AS exhibit a strong dislike of having their head touched or their hair disturbed while others like to be touched but dislike loud noises. Sensory overload may exacerbate problems faced by such children at school or indeed adults at work, where levels of noise in the classroom or workplace can become intolerable for them. Some are unable to block out, as in habituation, certain repetitive or background stimuli, such as the constant ticking of a clock, or a television in another room of the house. Whereas most children stop registering this sound after a short time and can hear it only if they consciously attend to it, a child with AS can become distracted, agitated, or even (in cases where the child has problems with regulating emotions such as anger) aggressive if the sound persists.

Tony Attwood states that a teacher may spend considerable time interpreting and correcting an AS child's indecipherable scrawl. The child is also aware of the poor quality of his or her handwriting and may be reluctant to engage in activities that involve extensive writing. Unfortunately for some children and adults, high school teachers and prospective employers may consider the neatness of handwriting as a measure of intelligence and personality. The child may require assessment by an occupational therapist and remedial exercises, but modern technology can help minimize this problem. A parent or teacher aide could also act as the child's scribe or proofreader to ensure the legibility of the child's written answers or homework.

Alexithymia is a personality trait of people who have difficulty recognizing, processing, and regulating emotions. Uta Frith reported that alexithymia overlaps with AS and that at least half of the Asperger syndrome subjects in a study obtained scores on the Toronto Alexithymia Scale (TAS-20) that indicate severe impairment. Other researchers concur that the conditions overlap; both conditions are characterized by core disturbances in speech and language and social relationships and the limbic system and prefrontal cortex may be involved in both. Alexithymic traits in AS may be linked to depression or anxiety; the mediating factors are unknown and it is possible that alexithymia predisposes to anxiety.

Diagnosis

Asperger's Disorder is defined in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) by six main criteria:

1. qualitative impairment in social interaction
2. restricted, repetitive and stereotyped behaviors and interests
3. significant impairment in important areas of functioning
4. no significant delay in language development
5. no significant delay in cognitive development, self-help skills or adaptive behaviors (other than social interaction)
6. criteria are not met for another specific pervasive developmental disorder or schizophrenia.

Developmental screening during a routine check-up by a general practitioner or pediatrician may identify signs that warrant further investigation. This will require a comprehensive team evaluation to either confirm or exclude a diagnosis of AS. This team usually includes a psychologist, neurologist, psychiatrist, speech and language pathologist, occupational therapist and other professionals with expertise in diagnosing children with AS. Observation should occur across multiple settings; the social disability in AS may be more evident during periods when social expectations are unclear and children are free of adult direction. A comprehensive evaluation includes neurologic and genetic assessment, with in-depth cognitive and language testing to establish IQ and evaluate psychomotor function, verbal and nonverbal strengths and weaknesses, style of learning, and skills for independent living. An assessment of communication strengths and weaknesses includes the evaluation of nonverbal forms of communication (gaze and gestures); the use of non-literal language (metaphor, irony, absurdities and humor); patterns of speech inflection, stress and volume; pragmatics (turn-taking and sensitivity to verbal cues); and the content, clarity and coherence of conversation. Testing may include an audiological referral to exclude hearing impairment. The determination of whether there is a family history of autism spectrum conditions is important. A medical practitioner will diagnose on the basis of the test results and the child’s developmental history and current symptoms. Because multiple domains of functioning are involved, a multidisciplinary team approach is critical; an accurate assessment of the individual's strengths and weaknesses is more useful than a diagnostic label. Delayed or mistaken diagnosis is a serious problem that can turn out to be traumatic for individuals and families; diagnosis based solely on a neurological, speech and language, or educational attainment may yield only a partial diagnosis.

Parents of children with AS can typically trace differences in their children's development to as early as 30 months of age, although diagnosis is not made on average until the age of 11. By definition, children with AS develop language and self-help skills on schedule, so early signs may not be apparent and the condition may not be diagnosed until later childhood. Impairment in social interaction is sometimes not in evidence until a child attains an age at which these behaviors become important; social disabilities are often first noticed when children encounter peers in daycare or preschool. Diagnosis is most commonly made between the ages of four and eleven, and one study suggests that diagnosis cannot be rendered reliably before age four.

Asperger syndrome can be misdiagnosed as a number of other conditions, leading to medications that are unnecessary or even cause deterioration in behavior; the condition may be at the root of treatment-resistant mental illness in adults. Diagnostic confusion burdens individuals and families and may cause them to seek unhelpful therapies. Conditions that must be considered in a differential diagnosis include other pervasive developmental disorders (autism, PDD-NOS, childhood disintegrative disorder, Rett disorder), schizophrenia spectrum disorders (schizophrenia, schizotypal disorder, schizoid personality disorder), attention-deficit hyperactivity disorder, obsessive compulsive disorder, depression, semantic pragmatic disorder, multiple complex developmental disorder and nonverbal learning disorder. Other problems to be considered in the differential diagnosis include selective mutism, stereotypic movement disorder and bipolar disorder as well as traumatic brain injury or birth trauma, conduct disorder, Cornelia De Lange syndrome, fetal alcohol syndrome, fragile X syndrome, dyslexia, Fahr syndrome, hyperlexia, leukodystrophy, multiple sclerosis and Triple X syndrome.

Multiple sets of diagnostic criteria

The diagnosis of AS is complicated by the use of several different screening instruments. In addition to the DSM-IV and the similar World Health Organization ICD-10 criteria, other sets of diagnostic criteria for AS are the Szatmari et al. criteria and the Gillberg and Gillberg criteria.

The ICD-10 criteria are virtually identical to DSM-IV: ICD-10 adds the statement that motor clumsiness is usual (although not necessarily a diagnostic feature); ICD-10 adds the statement that isolated special skills, often related to abnormal preoccupations, are common but are not required for diagnosis; and the DSM-IV requirement for clinically significant impairment in social, occupational, or other important areas of functioning is not included in ICD-10.

The Gillberg and Gillberg criteria are considered closest to Asperger's original description of the syndrome; the aggression, rage and abnormal prosody that defined Asperger's patients are not mentioned in any criteria. Compared with the DSM-IV and ICD-10 criteria, the requirements of normal early language and cognitive development are not mentioned by Szatmari et al., whereas speech delay is allowed in the Gillberg and Gillberg criteria. Szatmari et al. emphasize solitariness, and both Gillberg and Szatmari include "odd speech" and "language" in their criteria. Although Szatmari does not mention stereotyped behaviors, one of four described stereotyped functions is required by DSM-IV and ICD-10, and two are required by Gillberg and Gillberg. Abnormal responses to sensory stimuli are not mentioned in any diagnostic scheme, although they have been associated with AS. Because DSM-IV and ICD-10 exclude speech and language difficulties, these definitions exclude some of the original cases described by Hans Asperger. According to one researcher, the majority of individuals with AS do have speech and language abnormalities, and the recent DSM–IV says that "the occurrence of 'no clinically significant delays in language does not imply that individuals with Asperger Disorder have no problems with communication' (American Psychiatric Association, 2000, p. 80)".

The DSM-IV and ICD-10 diagnostic criteria have been criticized for being too broad and inadequate for assessing adults, overly narrow (particularly in relation to Hans Asperger's original description of individuals with AS), and vague; results of a large study in 2007 comparing the four sets of criteria point to a "huge need to reconsider the diagnostic criteria of AS". The study found complete overlap across all sets of diagnostic criteria in the impairment of social interaction with the exception of four cases not diagnosed by the Szatmari et al. criteria because of its emphasis on social solitariness. Lack of overlap was strongest in the language delay and odd speech requirements of the Gillberg and the Szatmari requirements relative to DSM-IV and ICD-10, and in the differing requirements regarding general delays.

Causes

Asperger described common symptoms among his patients' family members, especially fathers, and research supports this observation and suggests a genetic contribution to AS. Although no specific gene has yet been identified, multiple factors are believed to play a role in the expression of autism, given the phenotypic variability seen in this group of children. Evidence for a genetic link is the tendency for AS to run in families and an observed higher incidence of family members who have behavioral symptoms similar to AS but in a more limited form (for example, slight difficulties with social interaction, language, or reading). Most research suggests that all autism spectrum disorders have shared genetic mechanisms, but AS may have a stronger genetic component than autism. There is probably a common group of genes where particular alleles render an individual vulnerable to developing AS; if this is the case, the particular combination of alleles would determine the severity and symptoms for each individual with AS. No gene has been identified for AS, although studies suggest specific genetic abnormalities: such as various types of chromosomal translocations in chromosomes 1, 5, 11, 13, 14, 15 and 17; autosomal fragile site, fragile X syndrome, fragile Y, and 21pþ. Anomalies in chromosome 22 were related to the diagnosis of autism and Asperger syndrome in five children. The distal tip of the long arm of the chromosome 22 contains the SHANK3 gene, which is thought to have a role in the maturation and maintenance of brain synapses. The deletion of this part of the chromosome (22q13 deletion syndrome) was found in low-functioning autistic subjects, and its duplication observed in a subject diagnosed with Asperger syndrome.

Environmental factors may interact with genetic influences to play a role in the cause of ASDs, but research has identified no consistent correlations. There is strong evidence that genetic factors play a major role in the causes of autism spectrum disorders, while none of the possible environmental causes has been confirmed by scientific investigation.

Mechanism

Brain imaging techniques have revealed structural and functional differences in specific regions of the brains of AS children; these are most likely caused by the abnormal migration of embryonic cells during fetal development, which affects the final structure and connectivity of the brain, resulting in alterations in the neural circuits that control thought and behavior. Although progress has been made, brain imaging technologies have failed to identify the specific underpinnings of AS or factors that distinguish it from other ASDs and no clear pathology common to individuals with AS has emerged. Functional MRI has provided interesting findings, but no convincing evidence reproducibly indicates differences among AS and other ASDs.

One study reported a reduction of brain activity in the frontal lobe of AS children when they were asked to respond to tasks that required them to use their judgment. These differences in activity were also seen when children were asked to respond to facial expressions. Another study, of brain function in adults with AS, revealed abnormal levels of some proteins and demonstrated a correlation between these levels and obsessive and repetitive behaviors. Possible differences in AS include: gray tissue anomalies, left temporal lobe damage, and left occipital hypoperfusion. Other possible causative mechanisms include serotonin dysfunction and cerebellar dysfunction. Differences in brain volumes—such as enlarged amygdala and hippocampus—have been linked to autism; the most robust findings are of the reduced size of the corpus callosum and rapid brain growth and increased brain volume in early childhood that normalizes in mid-childhood. Other research suggests abnormal right hemisphere functioning in AS, dysfunction in brain regions affecting social cognition, and problems with functional connectivity among separate brain regions.

Simon Baron-Cohen proposes a model for Asperger's that extends the extreme male brain theory, which hypothesizes that autism is an extreme case of the male brain, defined psychometrically as individuals in whom systemizing is better than empathizing. Hyper-systemizing hypothesizes that autistic individuals can systematize—that is, they can develop internal rules of operation to handle internal events—but are less effective at empathizing by handling events generated by other agents. This in turn is related to the earlier theory of mind, which hypothesizes that autistic behavior arises from an inability to ascribe mental states to oneself and others. Two studies showed that Asperger subjects had a second-order theory of mind; compared to younger or more impaired autistic individuals, they were able to understand problems of the type "Peter thinks that Jane thinks that ..." although their explanationns of their solutions did not use mental states. There is some evidence that the mind-reading capacity of children in the higher-functioning range of the autistic spectrum are intact.

Treatment

The goal of treatment is the development of age-appropriate social, communication and vocational abilities, and the successful management of distressing symptoms, aiming to teach through explicit instruction the skills that are not naturally acquired during development. Intervention should be tailored to the needs of the individual child, based on multidisciplinary assessment. Although progress has been made, data supporting the efficacy of particular interventions are limited.

The ideal treatment for AS coordinates therapies that address the three core symptoms of the disorder: poor communication skills, obsessive or repetitive routines, and physical clumsiness. While most professionals agree that the earlier the intervention, the better, there is no single best treatment package. AS treatment resembles that of other high-functioning ASDs, except that it takes into account the linguistic capabilities, verbal strengths, and nonverbal vulnerabilities of individuals with AS. A typical treatment program generally includes:

• the training of social skills for more effective interpersonal interactions;
• cognitive behavioral therapy to improve the management of anxiety or explosive emotions, and to reduce the prevalence of obsessive interests and repetitive routines;
• medication, for coexisting conditions such as depression and anxiety;
• occupational or physical therapy to assist with poor sensory integration and motor coordination;
• specialized speech therapy, to help with the pragmatics of the "give and take" of normal conversation;
• the training and support of parents, particularly in behavioral techniques to use in the home.

There have been many studies on psychologically based early intervention programs; most of these are case studies of up to five participants. These studies typically examine non-core autistic problem behaviors such as self-injury, aggression, noncompliance, stereotypies and spontaneous language. Despite the widespread application of social skills training, its effectiveness is not firmly established. A randomized controlled study of a model for training parents in problem behaviors in their children with AS showed that parents attending a 1-day workshop or six individual lessons reported fewer behavioral problems, while parents receiving the individual lessons reported less intense behavioral problems in their AS children. Vocational training is important to teach job interview etiquette and workplace behavior to older children and adults with AS, and organization software and personal data assistants to improve the work and life management of people with AS are useful.

No medications specifically target AS or directly treat the core symptoms of autism spectrum disorders; research into the efficacy of pharmaceutical intervention for AS is limited. However, it is essential to diagnose and treat comorbid conditions; medication can be effective in combination with behavioral interventions and environmental accommodations in treating comorbid symptoms such as anxiety, depression, inattention and aggression. Care must be taken in the management of pharmacotherapy, as side-effects with psychotropic medications are not uncommon; abnormalities in metabolism, cardiac conduction times, and an increased risk of diabetes have been raised as concerns with these medications. Knowledge of comorbid conditions is crucial when prescribing medications to treat AS.

The atypical neuroleptic medications risperidone and olanzapine have been shown to reduce the associated symptoms of AS. Risperidone can reduce repetitive and self-injurious behaviors, aggressive outbursts and impulsivity, as well as improve stereotypical patterns of behavior and social relatedness. The selective serotonin reuptake inhibitors (SSRIs) fluoxetine and sertraline have been effective in treating repetitive behaviors and restricted interests, and one case report noted improved sleep and reduced repetitive behaviors in association with fluvoxamine.

Unintended side effects of medication and intervention have largely been ignored in the literature about treatment programs for children and adults. SSRIs can lead to behavioral activation, even at low doses—families are cautioned to be alert to manifestations of behavioral activation such as increased impulsivity, aggression and sleep disturbance . Weight gain and fatigue are commonly reported side effects of risperidone, which may also lead to increased risk for extrapyramidal symptoms such as restlessness and dystonia. Risperidone increases serum prolactin levels, although the long-term sequelae are unknown. Sedation and weight gain are more common with olanzapine, which has also been linked with diabetes. Sedative side-effects in school-age children have ramifications for classroom learning. Pharmacological treatments can be challenging, because individuals with AS may be unable to identify and communicate their internal moods and emotions or to tolerate side-effects that for most people would not be problematic.

Shift in view

Autistic people have contributed to a shift in perception of autism spectrum disorders as complex syndromes rather than diseases that must be cured. Proponents of this view reject the notion that there is an "ideal" brain configuration and that any deviation from the norm is pathological; they demand tolerance for what they call their neurodiversity. These views are the basis for the autistic rights and autistic pride movements.

Researcher Simon Baron-Cohen has argued that both AS and high-functioning autism are "differences" and not necessarily "disabilities." In proposing the more neutral term "difference", he suggests a subtle but important shift of emphasis to characterization of autism as a different cognitive style; this small shift in a term could mean the difference between a diagnosis of AS being received as a family tragedy, or as interesting information, such as learning that a child is left-handed. People with Asperger's, according to Baron-Cohen, "might not necessarily be disabled in an environment in which an exact mind, attracted to detecting small details, is an advantage". Autism researcher Tony Attwood argues that "... the unusual profile of abilities that we define as Asperger's Syndrome has probably been an important and valuable characteristic of our species throughout evolution".

Prognosis

As of 2006, no studies addressing the long-term outcome of individuals with AS are available and there are no systematic long-term follow-up studies of children with AS. Individuals with AS appear to have normal life expectancy but have an increased prevalence of comorbid psychiatric conditions such as depression, mood disorders, and obsessive-compulsive disorder that may significantly effect prognosis. Although the social impairment is believed to be lifelong, outcome is generally more positive than with individuals with lower functioning autism spectrum disorders.

Children with AS are vulnerable to being teased and victimized; some may require special education services because of their social and behavioral difficulties although many attend regular education classes. Adolescents with AS may exhibit ongoing difficulty with self-care, organization and disturbances in social and romantic relationships; despite high cognitive potential, most remain at home, although some do marry and work independently. The "different-ness" adolescents experience can be traumatic. Although the deficits associated with AS are often debilitating, many individuals experience positive outcomes—particularly those who are able to excel in areas less dependent on social interaction, such as mathematics, music, and the sciences. Reports suggest that many people with AS are highly creative and accomplish innovative research in fields such as computer science, mathematics, and physics. Baron-Cohen reports a link between AS and high-achieving mathematicians, physicists and computer scientists that shows that the condition need not be an obstacle to achievement. The symptoms of AS can at some point "fade to normal" and people with AS can become valued workers as adults because of the "intensity of interest and volume of knowledge" that they may bring to idiosyncratic subjects, but they may lose employment if impaired understanding of social norms leads to poor judgment in work site behavior.

Education of families is critical in developing strategies for understanding strengths and weaknesses; prognosis is improved when individuals with AS have supportive families who are knowledgeable about Asperger's. Prognosis may be improved by diagnosis at a younger age that allows for early interventions, while interventions in adulthood are valuable but less beneficial. There are legal implications for individuals with AS as they run the risk of exploitation by others and may be unable to comprehend the societal implications of their actions. The hypothesis that the combination of intact intellectual and linguistic ability with limited empathy and social understanding may predispose individuals with AS to violent or criminal behavior has been investigated and found to be unsupported by data.

Epidemiology

The incidence of AS is not well established, but conservative estimates using the DSM-IV criteria indicate that two to three of every 10,000 children have the condition, making it rarer than autistic disorder itself. A computerized registry in Denmark indicates an annual incidence of 1.4 per 10,000 for AS.

A 2003 review of epidemiological studies found prevalence rates ranging from .03 to 4.8 per 1,000; the authors suggested a working rate of .26 per 1,000. A 1993 Sweden study found the prevalence of AS was 3.6 per 1,000 among school-aged children aged 7–16 using Gillberg's criteria, rising to 7.1 per 1,000 if suspected cases are included. The estimate is convincing for Sweden, but the findings may not apply elsewhere because they are based on a homogeneous population. The Sweden study demonstrated that AS may be more common than once thought and may be currently underdiagnosed.

Prevalence estimates vary according to the diagnostic criteria employed. An epidemiological study of 5,484 eight-year-old children in Finland found 2.9 children per 1,000 met the ICD-10 criteria for an AS diagnosis, 2.7 per 1,000 for Gillberg and Gillberg criteria, 2.5 for DSM-IV and 1.6 for Szatmari et al. The number of children diagnosed as having AS according to any of the four criteria was 4.3 per 1,000. Leekam et al. documented significant differences between Gillberg's criteria and the ICD-10 criteria.

Like other autism spectrum disorders, AS prevalence estimates for males are higher than for females. The Sweden study found a 4:1 male to female ratio in subjects meeting Gillberg's criteria for AS, but a lower 2.3:1 ratio when suspected or borderline cases were included. The Finland study found a "somewhat surprising" male-to-female ratio according to DSM-IV criteria of 0.8:1; Gillberg and Gillberg criteria yielded a 2:1 ratio and the ratio when including children diagnosed per any of the four sets of diagnostic criteria was 1.7:1. Females with AS may not be recognized in studies as they tend to be superficially more sociable than boys, although closer examination reveals problems in social interaction.

Comorbidities

Most patients presenting in clinical settings with AS have other comorbid psychiatric disorders; children are likely to present with attention-deficit hyperactivity disorder (ADHD), while depression is a common diagnosis in adolescents and adults. Many children with AS are initially misdiagnosed with ADHD. Individuals with AS may also be diagnosed with oppositional defiant disorder, antisocial personality disorder, tic disorders and Tourette syndrome, general anxiety disorder, bipolar disorder, obsessive compulsive disorder or obsessive-compulsive personality disorder.

The conditions most commonly co-occurring with AS are depression and anxiety; comorbidity of anxiety and depression in persons with AS is estimated at 65%. Anxiety may stem from preoccupation over possible violations of routines and rituals or result from being placed in a situation without a clear schedule or expectations. Social anxiety (concern with failing in social encounters) may also manifest. Depression is often the result of chronic frustration from repeated failure to engage others socially, and mood disorders requiring treatment may develop.

The particularly high comorbidity with anxiety often requires special attention; one study reported that about 84% of individuals with a pervasive developmental disorder also met the criteria for anxiety disorder. Because of the social differences experienced by those with AS, such as trouble initiating or maintaining a conversation or adherence to strict rituals or schedules, additional stress to any of these activities may result in feelings of anxiety, which can negatively affect multiple areas of one's life, including school, family, and work. Anxiety disorders can be treated with medication or individual and group cognitive behavioral therapy, where relaxation or distraction-type activities may be used along with other techniques to diffuse the feelings of anxiety.

Psychosocial factors may contribute to poor adjustment or psychiatric issues. An Internet survey of middle-class mothers of children with AS and nonverbal learning disorders found peer and sibling victimization of the children was common; 94% of mothers reported peer victimization of their children. According to the mothers, in the year leading up to the study, almost three-quarters of the children had been hit by peers or siblings and 75% had been emotionally bullied. More seriously, 10% of the children were attacked by a gang and 15% were victims of nonsexual assaults to the genitals. Many of the children ate alone at lunch or were picked last for sports teams, and a third had not been invited to a birthday party in the past year.

Reports of high frequencies of medical anomalies common to AS and autism have not been replicated. Reports have associated AS with medical conditions such as aminoaciduria and ligamentous laxity, but these have been case reports or small studies and no factors have been associated with AS across studies. An increased rate of epilepsy is reported in individuals with AS, and there is a high rate (51%) of non-verbal learning disability.

History

Asperger syndrome is a relatively new diagnosis in the field of autism, named in honor of Hans Asperger (1906–80), an Austrian psychiatrist and pediatrician. An English psychiatrist, Lorna Wing popularized the term "Asperger's syndrome" in a 1981 publication; the first book in English on Asperger syndrome was written by Uta Frith in 1991 and the condition was subsequently recognized in formal diagnostic manuals later in the 1990s.

Asperger was the director of the University Children's Clinic in Vienna, spending most of his professional life in Vienna and publishing largely in German. In 1944, Asperger described in the paper " 'Autistic psychopathy' in childhood" four children in his practice who had difficulty in integrating themselves socially. Although their intelligence appeared normal, the children lacked nonverbal communication skills, failed to demonstrate empathy with their peers, and were physically clumsy. Their speaking was either disjointed or overly formal, and their all-absorbing interest in a single topic dominated their conversations. Asperger called the condition "autistic psychopathy" and described it as primarily marked by social isolation. Asperger called his young patients "little professors", and believed the individuals he described would be capable of exceptional achievement and original thought later in life.

Two subtypes of autism were described between 1943 and 1944 by two Austrian researchers working independently—Asperger and Austrian-born child psychiatrist Leo Kanner (1894–1981). Kanner immigrated to the United States in 1924; he described a similar syndrome in 1943, known as "classic autism" or "Kannerian autism", characterized by significant cognitive and communicative deficiencies, including delayed or absent language development. Kanner's descriptions were influenced by the developmental approach of Arnold Gesell, while Asperger was influenced by accounts of schizophrenia and personality disorders. Asperger's frame of reference was Eugen Bleuler's typology, which Gillberg described as "out of keeping with current diagnostic manuals", adding that Asperger's desriptions are "penetrating but not sufficiently systematic". Asperger was unaware of Kanner's description published a year before his; the two researchers were separated by an ocean and a raging war, and Asperger's descriptions were ignored in the United States. During his lifetime, Asperger's work, in German, remained largely unknown outside the German-speaking world.

According to Ishikawa and Ichihashi in the Japanese Journal of Clinical Medicine, the first author to use the term Asperger's syndrome in the English-language literature was the German physician, Gerhard Bosch. Between 1951 and 1962, Bosch worked as a psychiatrist at Frankfurt University. In 1962, he published a monograph detailing five case histories of individuals with PDD that was translated to English eight years later, becoming one of the first to establish German research on autism, and attracting attention outside the German-speaking world.

Lorna Wing is credited with widely popularizing the term "Asperger's syndrome" in the English-speaking medical community in her 1981 publication of a series of case studies of children showing similar symptoms. Wing also placed AS on the autism spectrum, although Asperger was uncomfortable characterizing his patient on the continuum of autistic spectrum disorders. She chose "Asperger's syndrome" as a neutral term to avoid the misunderstanding equated by the term autistic psychopathy with sociopathic behavior. Wing's translation and publication effectively introduced the diagnostic concept into American psychiatry and renamed the condition as Asperger's; however, her accounts blurred some of the distinctions between Asperger's and Kanner's descriptions because she included some mildly retarded children and some children who presented with language delays early in life.

The first systematic studies appeared in the late 1980s in publications by Tantam (1988) in the UK, Gillberg and Gilbert in Sweden (1989), and Szatmari, Bartolucci and Bremmer (1989) in North America. The diagnostic criteria for AS were outlined by Gillberg and Gillberg in 1989; Szatmari also proposed criteria in 1989. Asperger's work became more widely available in English when Uta Frith, an early researcher of Kannerian autism, translated his original paper in 1991. AS became a distinct diagnosis in 1992, when it was included in the 10th published edition of the World Health Organization’s diagnostic manual, International Classification of Diseases (ICD-10); in 1994, it was added to the fourth edition of the Diagnostic and statistical manual of mental disorders (DSM-IV) as Asperger's Disorder.

Less than two decades after the widespread introduction of AS to English-speaking audiences, there are hundreds of books, articles and websites describing it; prevalence figures have increased dramatically, with AS recognized as an important subgroup of the autism spectrum. However, questions remain concerning many aspects of AS; whether it should be a separate condition from high-functioning autism is a fundamental issue requiring further study. The diagnostic validity of Asperger syndrome is tentative, there is little consensus among clinical researchers about the usage of the term "Asperger's syndrome", and there are questions about the empirical validation of the DSM-IV and ICD-10 criteria. It is likely that the definition of the condition will change as new studies emerge and it will eventually be understood as a multifactorial heterogenous neurodevelopmental disorder involving a catalyst that results in prenatal or perinatal changes in brain structures.

Cultural aspects

People with AS may refer to themselves in casual conversation as "aspies", coined by Liane Holliday Willey in 1999, or as an "Aspergian". The term "neurotypical" (NT) describes a person whose neurological development and state are typical, and is often used to refer to people who are non-autistic.

A Wired magazine article, "The Geek Syndrome", suggested that AS is more common in Silicon Valley, a haven for computer scientists and mathematicians. It posited that AS may be the result of assortative mating by geeks in mathematical and technological areas. AS can be found in all occupations, however, and is not limited to those in the math and science fields.

The popularization of the Internet has allowed individuals with AS to communicate with each other in a way that was not previously possible due to the rarity and the geographic dispersal of individuals with AS. As a result of increasing ability to connect with one another, a subculture of "Aspies" has formed. Internet sites like Wrong Planet have made it easier for individuals to connect with each other.

See also

• Picture thinking
• Autistic Pride Day

References

• Attwood, Tony (1997). Asperger's Syndrome: A Guide for Parents and Professionals. Jessica Kingsley Pub., London. ISBN 1-85302-577-1

1. ^ BehaveNet® Clinical Capsule™. DSM-IV & DSM-IV-TR: Asperger's Disorder (AD). Retrieved 15 July 2007.
2. ^ Baron-Cohen S, Wheelwright S, Skinner R, Martin J, Clubley E (2001). "The autism-spectrum quotient (AQ): evidence from Asperger syndrome/high-functioning autism, males and females, scientists and mathematicians". Journal of autism and developmental disorders. 31 (1): 5–17. PMID 11439754.{{cite journal}}: CS1 maint: multiple names: authors list (link) Erratum in: J Autism Dev Disord 2001 Dec;31(6):603.
3. James I (2003). "Singular scientists". J R Soc Med. 96 (1): 36–9. PMID 12519805.
4. ^ Brasic, JR. Pervasive Developmental Disorder: Asperger Syndrome. eMedicine.com (April 10, 2006). Retrieved 15 July 2007.
5. Attwood (1997), pp. 129–40
6. Attwood (1997), pp. 28–29
7. Schultz RT, Gauthier I, Klin A; et al. (2000). "Abnormal ventral temporal cortical activity during face discrimination among individuals with autism and Asperger syndrome". Arch. Gen. Psychiatry. 57 (4): 331–40. PMID 10768694. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
8. Rühl D, Bölte S, Poustka F (2001). "". Der Nervenarzt (in German). 72 (7): 535–40. PMID 11478225.{{cite journal}}: CS1 maint: multiple names: authors list (link)
9. ^ Mayes SD, Calhoun SL, Crites DL (2001). "Does DSM-IV Asperger's disorder exist?". Journal of abnormal child psychology. 29 (3): 263–71. PMID 11411788.{{cite journal}}: CS1 maint: multiple names: authors list (link)
10. ^ Klin A (2006). "Autism and Asperger syndrome: an overview". Rev Bras Psiquiatr. 28 (Suppl 1): S3–S11. PMID 16791390.
11. ^ National Institute of Neurological Disorders and Stroke (NINDS) (July 31 2007). Asperger Syndrome Fact Sheet. Retrieved 24 August 2007.
12. ^ Kasari C, Rotheram-Fuller E (2005). "Current trends in psychological research on children with high-functioning autism and Asperger disorder". Curr Opin Psychiatry. 18 (5): 497–501. doi:10.1097/01.yco.0000179486.47144.61. PMID 16639107.
13. ^ Blacher J, Kraemer B, Schalow M (2003). "Asperger Syndrome and High Functioning Autism: Research Concerns and Emerging Foci". Current Opinion in Psychiatry. 16 (5): 535–542. Retrieved 2007-08-18.{{cite journal}}: CS1 maint: multiple names: authors list (link)
14. Leekam S, Libby S, Wing L, Gould J, Gillberg C (2000). "Comparison of ICD-10 and Gillberg's Criteria for Asperger Syndrome". Autism. 4 (1F pages=11–28). doi:10.1177/1362361300004001002. {{cite journal}}: Missing pipe in: |issue= (help)CS1 maint: multiple names: authors list (link)
15. Dingfelder, Sadie. A Dilemma of Definition. American Psychological Association, Volume 35, No. 11 December 2004, page 48.
16. ^ Eisenmajer R, Prior M, Leekam S; et al. (1998). "Delayed language onset as a predictor of clinical symptoms in pervasive developmental disorders". Journal of autism and developmental disorders. 28 (6): 527–33. PMID 9932239. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
17. ^ Mayes SD, Calhoun SL (2001). "Non-significance of early speech delay in children with autism and normal intelligence and implications for DSM-IV Asperger's disorder". Autism : the international journal of research and practice. 5 (1): 81–94. PMID 11708393.
18. Koyama T, Tachimori H, Osada H, Takeda T, Kurita H (February 2007). "Cognitive and symptom profiles in Asperger's syndrome and high-functioning autism". Psychiatry Clin Neurosci. 61 (1): 99–104. PMID 17239046.{{cite journal}}: CS1 maint: multiple names: authors list (link)
19. Attwood (1997), pp. 195–196
20. Ozonoff S, Rogers SJ, Pennington BF (1991). "Asperger's syndrome: evidence of an empirical distinction from high-functioning autism". Journal of child psychology and psychiatry, and allied disciplines. 32 (7): 1107–22. PMID 1787139.{{cite journal}}: CS1 maint: multiple names: authors list (link)
21. Attwood, Tony (2003). Is There a Difference Between Asperger's Syndrome and High Functioning Autism? (PDF). Sacramento Asperger Syndrome Information & Support. Retrieved on 2007-08-15.
22. ^ Szatmari P (2000). "The classification of autism, Asperger's syndrome, and pervasive developmental disorder". Can J Psychiatry. 45 (8): 731–38. PMID 11086556.
23. ^ Baskin JH, Sperber M, Price BH (2006). "Asperger syndrome revisited". Reviews in neurological diseases. 3 (1): 1–7. PMID 16596080.{{cite journal}}: CS1 maint: multiple names: authors list (link)
24. ^ McPartland J, Klin A (2006). "Asperger's syndrome". Adolescent medicine clinics. 17 (3): 771–88, abstract xiii. doi:10.1016/j.admecli.2006.06.010. PMID 17030291.
25. Myles, Brenda Smith; Trautman, Melissa; and Schelvan, Ronda (2004). The Hidden Curriculum: practical solutions for understanding unstated rules in social situations. Shawnee Mission, Kansas: Autism Asperger Publishing Co., 2004. ISBN 1-931282-60-9.
26. Levanthal-Belfer, Laurie and Coe, Cassandra (2004). Asperger Syndrome in Young Children: A Developmental Approach for Parents and Professionals. London: Jessica Kingsley Publishers, p. 161. ISBN 1-84310-748-1
27. Levanthal-Belfer and Coe (2004), pp. 160–161.
28. Attwood (1997), pp. 89–92.
29. Attwood (1997), pp. 57–66
30. Attwood (1997), pp. 165–169
31. Attwood (1997), pp. 89–102
32. ^ Wing L (1981). "Asperger's syndrome: a clinical account". Psychological medicine. 11 (1): 115–29. PMID 7208735. Retrieved 2007-08-15.
33. Hippler K, Klicpera C (2003). "A retrospective analysis of the clinical case records of 'autistic psychopaths' diagnosed by Hans Asperger and his team at the University Children's Hospital, Vienna". Philos. Trans. R. Soc. Lond., B, Biol. Sci. 358 (1430): 291–301. doi:10.1098/rstb.2002.1197. PMID 12639327.
34. ^ Gillberg IC, Gillberg C. "Asperger syndrome-some epidemiological considerations: A research note." J Child Psychol Psychiatry. 1989 Jul;30(4):631–38. PMID 2670981
35. ^ Bauer S. Asperger Syndrome. The Source (2000). Retrieved 7 July 2006.
36. Attwood (1997), pp. 80–82.
37. Attwood (1997), p. 78.
38. Attwood (1997), p. 82.
39. Attwood (1997), p. 109.
40. Myles BS, Huggins A, et al. Written language profile of children and youth with Asperger syndrome: From research to practice. Education and Training in Developmental Disabilities. 38:4 December 2003, 362–369. Abstract.
41. ^ Aquilla P, Yack E, Sutton S. "Sensory and motor differences for individuals with Asperger Syndrome: Occupational therapy assessment and intervention" in Stoddart, Kevin P. (Editor) (2005), p. 198.
42. Jankovic J, Mejia NI. "Tics associated with other disorders". Adv Neurol. 2006;99:61–68. PMID 16536352
43. Mejia NI, Jankovic J. Secondary tics and tourettism. Rev Bras Psiquiatr. 2005;27(1):11–17. PMID 15867978 Full-text PDF
44. Attwood (1997), p. 100.
45. Attwood (1997), p. 106.
46. Haviland MG, Warren WL, Riggs ML (2000). "An observer scale to measure alexithymia". Psychosomatics. 41 (5): 385–92. PMID 11015624. Retrieved 2007-08-10.{{cite journal}}: CS1 maint: multiple names: authors list (link)
47. ^ Frith U (2004). "Emanuel Miller lecture: confusions and controversies about Asperger syndrome". Journal of child psychology and psychiatry, and allied disciplines. 45 (4): 672–86. doi:10.1111/j.1469-7610.2004.00262.x. PMID 15056300. The study to which Frith refers is Hill E, Berthoz S, Frith U (2004). "Brief report: cognitive processing of own emotions in individuals with autistic spectrum disorder and in their relatives". Journal of Autism and Developmental Disorders. 34 (2): 229–235. doi:10.1023/B:JADD.0000022613.41399.14.{{cite journal}}: CS1 maint: multiple names: authors list (link)
48. Fitzgerald M, Bellgrove MA (2006). "The overlap between alexithymia and Asperger's syndrome". Journal of autism and developmental disorders. 36 (4): 573–6. doi:10.1007/s10803-006-0096-z. PMID 16755385. {{cite journal}}: |access-date= requires |url= (help)
49. Hill E, Berthoz S (2006). "Response to "Letter to the Editor: The Overlap Between Alexithymia and Asperger's syndrome", Fitzgerald and Bellgrove, Journal of Autism and Developmental Disorders, 36(4)". Journal of Autism and Developmental Disorders. 36 (8): 1143–1145. doi:10.1007/s10803-006-0287-7. {{cite journal}}: Unknown parameter |month= ignored (help)
50. ^ Tani P, Lindberg N, Joukamaa M; et al. (2004). "Asperger syndrome, alexithymia and perception of sleep". Neuropsychobiology. 49 (2): 64–70. doi:10.1159/000076412. PMID 14981336. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
51. ^ Foster B, King BH (2003). "Asperger syndrome: to be or not to be?". Curr. Opin. Pediatr. 15 (5): 491–94. PMID 14508298.
52. ^ Fitzgerald M, Corvin A (2001). Diagnosis and differential diagnosis of Asperger syndrome. Advances in Psychiatric Treatment 7: pp. 310–18.
53. ^ Ehlers S, Gillberg C. "The epidemiology of Asperger's syndrome: a total population study." J Child Psychol Psychiatry. 1993 Nov;34(8):1327–50. PMID 8294522 Lay summary. Cite error: The named reference "EhlGill" was defined multiple times with different content (see the help page).
54. Szatmari P, Bremner R, Nagy J (1989). "Asperger's syndrome: a review of clinical features". Canadian journal of psychiatry. Revue canadienne de psychiatrie. 34 (6): 554–60. PMID 2766209.{{cite journal}}: CS1 maint: multiple names: authors list (link)
55. ^ Mattila ML, Kielinen M, Jussila K; et al. (2007). "An epidemiological and diagnostic study of Asperger syndrome according to four sets of diagnostic criteria". Journal of the American Academy of Child and Adolescent Psychiatry. 46 (5): 636–46. doi:10.1097/chi.0b013e318033ff42. PMID 17450055. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
56. Baron-Cohen S, Wheelwright S, Robinson J, Woodbury-Smith M (2005). "The Adult Asperger Assessment (AAA): a diagnostic method" (PDF). Journal of autism and developmental disorders. 35 (6): 807–19. doi:10.1007/s10803-005-0026-5. PMID 16331530.{{cite journal}}: CS1 maint: multiple names: authors list (link)
57. Durand CM, Betancur C, Boeckers TM; et al. (2007). "Mutations in the gene encoding the synaptic scaffolding protein SHANK3 are associated with autism spectrum disorders". Nat. Genet. 39 (1): 25–27. doi:10.1038/ng1933. PMID 17173049. {{cite journal}}: |access-date= requires |url= (help); Explicit use of et al. in: |author= (help); Unknown parameter |laydate= ignored (help); Unknown parameter |laysource= ignored (help); Unknown parameter |laysummary= ignored (help)CS1 maint: multiple names: authors list (link)
58. Wing L, Potter D (2002). "The epidemiology of autistic spectrum disorders: is the prevalence rising?". Mental retardation and developmental disabilities research reviews. 8 (3): 151–61. doi:10.1002/mrdd.10029. PMID 12216059.
59. Kwon H, Ow AW, Pedatella KE, et al. "Voxel-based morphometry elucidates structural neuroanatomy of high-functioning autism and Asperger syndrome." Dev Med Child Neurol. 2004 Nov;46(11):760–64. PMID 15540637
60. McAlonan GM, Daly E, Kumari V; et al. (2002). "Brain anatomy and sensorimotor gating in Asperger's syndrome". Brain. 125 (Pt 7): 1594–606. PMID 12077008. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
61. Jones PB, Kerwin RW (1990). "Left temporal lobe damage in Asperger's syndrome". The British journal of psychiatry : the journal of mental science. 156: 570–2. PMID 2386870.
62. Ozbayrak KR, Kapucu O, Erdem E, Aras T (1991). "Left occipital hypoperfusion in a case with the Asperger syndrome". Brain Dev. 13 (6): 454–56. PMID 1810164.{{cite journal}}: CS1 maint: multiple names: authors list (link)
63. Murphy DG, Daly E, Schmitz N, et al. "Cortical serotonin 5-HT2A receptor binding and social communication in adults with Asperger's syndrome: an in vivo SPECT study." Am J Psychiatry. 2006 May;163(5):934–36. PMID 16648340
64. Gowen E, Miall RC. "Behavioural aspects of cerebellar function in adults with Asperger syndrome." Cerebellum. 2005;4(4):279–89. PMID 16321884
65. Schumann CM, Hamstra J, Goodlin-Jones BL, et al. "The amygdala is enlarged in children but not adolescents with autism; the hippocampus is enlarged at all ages." J Neurosci. 2004 14 July;24(28):6392–6401. PMID 15254095
66. Minshew N, Sweeney J, Bauman M, et al. Neurologic aspects of autism. In: Volkmar F, Paul R, Klin A, et al., eds. Handbook of autism and pervasive developmental disorders, vol 1. 3rd edition. Hoboken (NJ): John Wiley & Sons; 2005. p. 473–514. As cited in, McPartland J, Klin A (2006).
67. McKelvey JR, Lambert R, Mottron L, Shevell MI (1995). "Right-hemisphere dysfunction in Asperger's syndrome". J. Child Neurol. 10 (4): 310–14. PMID 7594267.{{cite journal}}: CS1 maint: multiple names: authors list (link) As cited in McPartland J, Klin A (2006).
68. Schultz R, Robins D. Functional neuroimaging studies of autism spectrum disorders. In: Volkmar F, Paul R, Klin A, et al, editors. Handbook of autism and pervasive developmental disorders, vol 1. 3rd edition. Hoboken (NJ): John Wiley & Sons; 2005. p. 515–33. As cited in McPartland J, Klin A (2006).
69. Welchew DE, Ashwin C, Berkouk K; et al. (2005). "Functional disconnectivity of the medial temporal lobe in Asperger's syndrome". Biol. Psychiatry. 57 (9): 991–98. doi:10.1016/j.biopsych.2005.01.028. PMID 15860339. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link) As cited in McPartland J, Klin A (2006).
70. Lawson J, Baron-Cohen S, Wheelwright S. "Empathising and systemising in adults with and without Asperger Syndrome." J Autism Dev Disord. 2004 Jun;34(3):301–10. PMID 15264498
71. Baron-Cohen S (2002). "The extreme male brain theory of autism". Trends Cogn Sci. 6 (6): 248–54. doi:10.1016/S1364-6613(02)01904-6. PMID 12039606.
72. Baron-Cohen S (2006). "The hyper-systemizing, assortative mating theory of autism". Prog Neuropsychopharmacol Biol Psychiatry. 30 (5): 865–72. doi:10.1016/j.pnpbp.2006.01.010. PMID 16519981.
73. Baron-Cohen S, Leslie AM, Frith U (1985). "Does the autistic child have a 'theory of mind'?" (PDF). Cognition. 21 (1): 37–46. doi:10.1016/0010-0277(85)90022-8. PMID 2934210. Retrieved 2007-06-28.{{cite journal}}: CS1 maint: multiple names: authors list (link)
74. Bowler DM (1992). ""Theory of mind" in Asperger's syndrome". Journal of child psychology and psychiatry, and allied disciplines. 33 (5): 877–93. PMID 1378848.
75. Rieffe C, Meerum Terwogt M, Stockmann L (2000). "Understanding atypical emotions among children with autism". Journal of autism and developmental disorders. 30 (3): 195–203. PMID 11055456.{{cite journal}}: CS1 maint: multiple names: authors list (link)
76. Khouzam HR, El-Gabalawi F, Pirwani N, Priest F (2004). "Asperger's disorder: a review of its diagnosis and treatment". Compr Psychiatry. 45 (3): 184–91. doi:10.1016/j.comppsych.2004.02.004. PMID 15124148.{{cite journal}}: CS1 maint: multiple names: authors list (link)
77. ^ Matson JL (2007). "Determining treatment outcome in early intervention programs for autism spectrum disorders: a critical analysis of measurement issues in learning based interventions". Research in developmental disabilities. 28 (2): 207–18. doi:10.1016/j.ridd.2005.07.006. PMID 16682171.
78. Rao PA, Beidel DC, Murray MJ (2007). "Social skills interventions for children with Asperger's syndrome or high-functioning autism: a review and recommendations". J Autism Dev Disord. doi:10.1007/s10803-007-0402-4. PMID 17641962.{{cite journal}}: CS1 maint: multiple names: authors list (link)
79. Sofronoff K, Leslie A, Brown W (2004). "Parent management training and Asperger syndrome: a randomized controlled trial to evaluate a parent based intervention". Autism : the international journal of research and practice. 8 (3): 301–17. doi:10.1177/1362361304045215. PMID 15358872.{{cite journal}}: CS1 maint: multiple names: authors list (link)
80. ^ Newcomer JW (2007). "Antipsychotic medications: metabolic and cardiovascular risk". The Journal of clinical psychiatry. 68 Suppl 4: 8–13. PMID 17539694.
81. ^ Chavez B, Chavez-Brown M, Sopko MA, Rey JA (2007). "Atypical antipsychotics in children with pervasive developmental disorders". Paediatric drugs. 9 (4): 249–66. PMID 17705564.{{cite journal}}: CS1 maint: multiple names: authors list (link)
82. Staller J (2006). "The effect of long-term antipsychotic treatment on prolactin". Journal of child and adolescent psychopharmacology. 16 (3): 317–26. doi:10.1089/cap.2006.16.317. PMID 16768639.
83. Frémaux T, Reymann JM, Chevreuil C, Bentué-Ferrer D (2007). "". L'Encéphale (in French). 33 (2): 188–96. PMID 17675914.{{cite journal}}: CS1 maint: multiple names: authors list (link)
84. Williams, Charmaine C. "In search of an Asperger culture," in Stoddart, Kevin. (Ed.) (2005), p. 246.
85. Williams (2005), p. 246. Williams writes: "The life prospects of people with AS would change if we shifted from viewing AS as a set of dysfunctions, to viewing it as a set of differences that have merit."
86. Dakin, Chris J. "Life on the outside: A personal perspective of Asperger syndrome," in Stoddart, Kevin (Ed.) (2005), pp. 352–353.
87. ^ Baron-Cohen, Simon. "Is asperger syndrome/high-functioning autism necessarily a disability?" Development and Psychopathology. 2000 Summer;12(3):489–500. PMID 11014749 Full-text PDF.
88. Attwood, Tony. The Complete Guide to Asperger's, Jessica Kingsley Publishers, London, UK., 2007, p. 12.
89. Gillberg C (1991). "Outcome in autism and autistic-like conditions". Journal of the American Academy of Child and Adolescent Psychiatry. 30 (3): 375–82. PMID 2055873.
90. Green J, Gilchrist A, Burton D, Cox A (2000). "Social and psychiatric functioning in adolescents with Asperger syndrome compared with conduct disorder". Journal of autism and developmental disorders. 30 (4): 279–93. PMID 11039855.{{cite journal}}: CS1 maint: multiple names: authors list (link)
91. Tantam D. "Asperger's syndrome in adulthood." In: Frith U, editor. Autism and Asperger syndrome. Cambridge: Cambridge University Press; 1991. pp. 147–83.
92. ^ Moran, Mark. Asperger's May Be Answer To Diagnostic Mysteries. Psychiatric News October 6, 2006, Volume 41, Number 19, page 21
93. Ghaziuddin M, Tsai L, Ghaziuddin N (1991). "Brief report: violence in Asperger syndrome, a critique". Journal of autism and developmental disorders. 21 (3): 349–54. PMID 1938780.{{cite journal}}: CS1 maint: multiple names: authors list (link)
94. Fombonne E. "Epidemiology of autistic disorder and other pervasive developmental disorders." J Clin Psychiatry. 2005;66 Suppl 10:3–8. PMID 16401144
95. Fombonne E, Tidmarsh L (2003). "Epidemiologic data on Asperger disorder". Child and adolescent psychiatric clinics of North America. 12 (1): 15–21, v–vi. PMID 12512396.
96. Leekam S, et al. (2000). Comparison of ICD-10 and Gillberg’s Criteria for Asperger Syndrome. The National Autistic Society, SAGE Publications, 2000.
97. Ghaziuddin M, Weidmer-Mikhail E, Ghaziuddin N (1998). "Comorbidity of Asperger syndrome: a preliminary report". Journal of intellectual disability research : JIDR. 42 ( Pt 4): 279–83. PMID 9786442.{{cite journal}}: CS1 maint: multiple names: authors list (link)
98. Gillberg C, Billstedt E (2000). "Autism and Asperger syndrome: coexistence with other clinical disorders". Acta psychiatrica Scandinavica. 102 (5): 321–30. PMID 11098802.
99. Muris P, Steerneman P, Merckelbach H, Holdrinet I, Meesters C (1998). "Comorbid anxiety symptoms in children with pervasive developmental disorders". Journal of anxiety disorders. 12 (4): 387–93. PMID 9699121.{{cite journal}}: CS1 maint: multiple names: authors list (link)
100. Dasari, Meena (May 24, 2005). "Asperger's Syndrome and Anxiety". NYU Child Study Center. Retrieved on 2007-08-15.
101. Little L (2002). "Middle-class mothers' perceptions of peer and sibling victimization among children with Asperger's syndrome and nonverbal learning disorders". Issues in comprehensive pediatric nursing. 25 (1): 43–57. PMID 11934121.
102. Cederlund M, Gillberg C (2004). "One hundred males with Asperger syndrome: a clinical study of background and associated factors". Developmental medicine and child neurology. 46 (10): 652–60. PMID 15473168.
103. ^ Baron-Cohen S, Klin A (2006). "What's so special about Asperger Syndrome?" (PDF). Brain and cognition. 61 (1): 1–4. doi:10.1016/j.bandc.2006.02.002. PMID 16563588.
104. Template:De icon Asperger, H. (1944), "Die 'Autistischen Psychopathen' im Kindesalter," Archiv für Psychiatrie und Nervenkrankheiten , 117:76–136
105. Asperger, H. (1944), Die 'Autistischen Psychopathen' im Kindesalter, Archiv fur Psychiatrie und Nervenkrankheiten, 117, pp. 76–136.
106. Kanner, L (1943). "Autistic Disturbances of Affective Contact". Nervous Child, 2;217–50.
107. Ishikawa G, Ichihashi K (2007). "". Nippon Rinsho (in Japanese). 65 (3): 409–18. PMID 17354550.
108. Template:De icon Bosch G (1962). Der frühkindliche Autismus - eine klinische und phänomenologisch-anthropologische. Untersuchung am Leitfaden der Sprache. Berlin: Springer.
109. Bosch G (1970). Infantile autism – a clinical and phenomenological anthropological investigation taking language as the guide. Berlin: Springer.
110. Bölte S, Bosch G. "Bosch's Cases: a 40 years follow-up of patients with infantile autism and Asperger syndrome" (PDF). Journal of Psychiatry. Retrieved 2007-08-20.
111. Willey, LH. Pretending to be Normal: Living with Asperger's Syndrome. Jessica Kingsley, London, 1999. ISBN 1-85302-749-9
112. Bringing Children Together. Aspergian Pride. Retrieved 2 July 2006.
113. Silberman, S (2001). The Geek Syndrome. Wired.com Retrieved 31 May 2006.
114. Nash, J. Madeleine (2002-05-06). "The Secrets of Autism". Time Magazine. Retrieved 2006-07-04. {{cite web}}: Check date values in: |date= (help)
115. Dekker, Martijn. On our own terms: Emerging autistic culture. AutisticCulture.com. Retrieved on 2007-08-15.

External links

• Template:Dmoz
• Asperger syndrome fact sheets - Fact sheets on diagnosis, early intervention, behaviors, family issues & personal stories, for both parents of a child on the autistic spectrum, and adults on the spectrum
• MedlinePlus Asperger Syndrome Resources
• CDC's "Learn the Signs. Act Early.” campaign - Information for parents on early childhood development and developmental disabilities
• Fresh Air with Terry Gross - National Public Radio (NPR) Program on Asperger's (2004 May 5)
• BBC's h2g2: "Autism and Asperger's Syndrome: The 'Little Professors'" (2006 April 19)
• Radio Times with Marty Moss-Coane Real audio feed of hour long public radio segment on coping with Asperger's (2007 February 7)

Template:Link FA

• Misplaced Pages articles needing rewrite from August 2007
• Articles with failed verification from August 2007
• Autism
• Pervasive Developmental Disorders
• Childhood psychiatric disorders
• Educational psychology
• Genetic disorders
• Neurological disorders
• Special education
• Syndromes