Asperger syndrome
Hot topic (15 November 2002)
Hot topics provide a short list of up-to-date references, books/reports/videos held by the BMA Library, and links to other relevant web resources, on a current news topic. Literature searches have been carried out using the MEDLINE and EMBASE databases, which make up the Library's MEDLINE Plus service. Results cover the last five years and have been limited to items held in BMA Library stock. References listed may be ordered via the Library's document delivery service for members. If you would like to suggest an area to be included as a future "hot topic" please email Clare Aitken (Sub-Librarian, Development).
Recent references from MEDLINE and EMBASE:
1. Baron-Cohen S et al. 'Obsessions' in children with autism or Asperger syndrome. Content analysis in terms of core domains of cognition. British Journal of Psychiatry 1999; 175:484-490.
Abstract: BACKGROUND: We report a survey of the content of obsessions in children with autism spectrum conditions. We use the term 'obsessions' narrowly, to indicate strong, repetitive interests. We predicted that obsessions would not cluster randomly, but rather would occur significantly more often in the domain of 'folk physics' (an interest in how things work), and significantly less often in the domain of 'folk psychology' (an interest in how people work). These predictions were tested relative to a control group of 33 children with Tourette syndrome. AIMS: To examine the content of autistic obsessions, and to test the theory that these reflect an evolved cognitive style of good folk physics alongside impaired folk psychology. METHOD: Ninety-two parents returned a questionnaire designed to determine the subject of their child's obsessional interests. The results were analysed in terms of core domains of cognition. RESULTS: Both predictions were confirmed. CONCLUSIONS: These results suggest that impaired f
olk psychology and superior folk physics are part of the cognitive phenotype of autism. A content-free theory of obsessions is inadequate
2. Bankier B et al. A case of Asperger's syndrome first diagnosed in adulthood. Psychopathology 1999; 32:43-46.
Abstract: A 25-year-old white male patient was admitted to the Department of Psychiatry, Division of Social Psychiatry, of the University of Vienna, Austria, for severe social withdrawal, selective mutism and outbursts of violence with attacks on his mother. Careful examination revealed the presence of all the typical symptoms of Asperger's syndrome. The diagnosis had never been made before, although the patient had a history of a difficult childhood with several admissions to a child psychiatric inpatient unit for 'obsessional neurosis' and an institutional career. It is stressed that, in view of the availability of treatments and the deleterious effect of the untreated condition in the sensitive years of personality development, early recognition and diagnosis of Asperger's syndrome are of utmost importance. [References: 8]
3. Schultz RT et al. Abnormal ventral temporal cortical activity during face discrimination among individuals with autism and Asperger syndrome. [see comments.]. Archives of General Psychiatry 2000; 57:331-340.
Abstract: BACKGROUND: Recognition of individual faces is an integral part of both interpersonal interactions and successful functioning within a social group. Therefore, it is of considerable interest that individuals with autism and related conditions have selective deficits in face recognition (sparing nonface object recognition). METHOD: We used functional magnetic resonance imaging (fMRI) to study face and subordinate-level object perception in 14 high-functioning individuals with autism or Asperger syndrome (the autism group), in comparison with 2 groups of matched normal controls (normal control group ] [NC1] and normal control group 2 [NC2]) (n = 14 for each). Regions of interest (ROIs) were defined in NC1 and then applied in comparisons between NC2 and the autism group. Regions of interest were also defined in NC2 and then applied to comparisons between NC1 and the autism group as a replication study. RESULTS: In the first set of comparisons, we found significant task x group interactions for the size
of activation in the right fusiform gyrus (FG) and right inferior temporal gyri (ITG). Post hoc analyses showed that during face (but not object) discrimination, the autism group had significantly greater activation than controls in the right ITG and less activation of the right FG. The replication study showed again that the autism group used the ITG significantly more for processing faces than the control groups, but for these analyses, the effect was now on the left side. Greater ITG activation was the pattern found in both control groups during object processing. CONCLUSIONS: Individuals with autism spectrum disorders demonstrate a pattern of brain activity during face discrimination that is consistent with feature-based strategies that are more typical of nonface object perception
4. Russell J et al. Action-monitoring and intention reporting in children with autism. Journal of Child Psychology & Psychiatry & Allied Disciplines 2001; 42:317-328.
Abstract: The 'mindblindness' theory of core cognitive impairment in autism and at least one of the executive theories of the core cognitive deficit both predict that children with autism should find it difficult to report what their intention was when it diverged from an outcome. The former predicts this because it takes intention reporting to require a 'theory of mind' and the latter predicts it because the theory posits an impairment in the monitoring of goal-directed actions. The latter also predicts impairments in the ability to monitor basic actions. Our three studies failed to support either of these views. Experiment 1 demonstrated intact abilities in the monitoring of basic actions (detecting which stimulus of a number of stimuli one is controlling). Experiment 2 demonstrated intact abilities in reporting an intention, both for self and for another agent, when the outcome was unintended but desired. In Experiment 3, using the novel 'transparent intentions task', we found (with a minor qualification)
intact ability in reporting on nonballistic intended actions when the result that the action achieved was unexpected. The implications of these results for views of the relation between theory of mind and executive difficulties in autism are discussed. [References: 43]
5. Patzold LM et al. An investigation into sleep characteristics of children with autism and Asperger's Disorder. Journal of Paediatrics & Child Health 1998; 34:528-533.
Abstract: Objective: The aim of the study was to investigate the specificity of sleep problems in children with autism and further explore the currently unclear association between sleep problems and daytime behaviour. Methodology: The Pervasive Developmental Disorder (PDD) group consisted of 31 children with autism and 7 children with Asperger's Disorder ranging in age from 44 to 152 months. The control group consisted of 36 children ranging in age from 63 to 171 months. The children were matched on age and gender, and group-matched on IQ level. A sleep diary was completed by parents over a 2- week period, in addition to several behaviour questionnaires. Results: Results showed that children in the PDD group exhibited qualitatively and quantitatively different sleep patterns to nonautistic control children. Conclusions: The findings were discussed in light of current literature concerning circadian rhythm dysfunction, social difficulties, and abnormal melatonin levels in children with autism. [References: 34
]
6. Ropar D et al. Are individuals with autism and Asperger's syndrome susceptible to visual illusions? Journal of Child Psychology & Psychiatry & Allied Disciplines 1999; 40:1283-1293.
Abstract: A recent finding that individuals with autism are not susceptible to illusions has been explained by Happe (1996) as a sign of "weak central coherence" at lower levels of processing. We investigated the phenomenon with a more sophisticated measure. In Experiment 1, individuals with autism, Asperger's syndrome, moderate learning difficulties, and typical development adjusted certain comparison lines and circles to make them appear to be the same size in four visual illusions. With a minor exception, the participants with autism and Asperger's syndrome evinced a systematic bias in their judgements in the illusion condition. The extent of this was no different from control participants. In a second experiment, a similar finding was obtained in a task where participants made verbal judgements about the stimuli. The results suggest that lower-level coherence in visual processing in autism is intact
7. Gillberg C. Asperger syndrome and high-functioning autism. British Journal of Psychiatry 1998; 172:200-209.
8. Klin A. Attributing social meaning to ambiguous visual stimuli in higher-functioning autism and Asperger syndrome: The Social Attribution Task. Journal of Child Psychology & Psychiatry & Allied Disciplines 2000; 41:831-846.
Abstract: More able individuals with autism and Asperger syndrome (AS) have been shown to pass relatively high level theory of mind (ToM) tasks without displaying commensurate levels of social adaptation in naturalistic settings. This paper presents a social cognitive procedure the Social Attribution Task (SAT) that reduces factors thought to facilitate ToM task performance without facilitating real-life social functioning. Sixty participants with autism (N = 20), AS (N = 20), and normally developing adolescents and adults (N = 20) with normative IQs were asked to provide narratives describing Heider and Simmel's (1944) silent cartoon animation in which geometric shapes enact a social plot. These narratives were coded in terms of the participants' abilities to attribute social meaning to the geometric cartoon. The SAT provides reliable and quantified scores on seven indices of social cognition. Results revealed marked deficits in both clinical groups across all indices. These deficits were not related to verb
al IQ or level of metalinguistic skills. Individuals with autism and AS identified about a quarter of the social elements in the story, a third of their attributions were irrelevant to the social plot, and they used pertinent ToM terms very infrequently. They were also unable to derive psychologically based personality features from the shapes' movements. When provided with more explicit verbal information on the nature of the cartoon, individuals with AS improved their performance slightly more than those with autism, but not significantly so
9. Rinehart NJ et al. Atypical interference of local detail on global processing in high-functioning autism and Asperger's disorder. Journal of Child Psychology & Psychiatry & Allied Disciplines 2000; 41:769-778.
Abstract: This study explored the claim that individuals with autism and Asperger's disorder tend to process locally rather than holistically. Participants observed a large or "global" number composed of smaller or "local" numbers. The response was contingent upon the identification of either the large stimulus or the small stimuli. Relative to age, sex, and IQ matched controls, global processing in children and adolescents with autism (N = 12) and Asperger's disorder (N = 12) was more vulnerable when the local stimuli were incongruent. The autism group made more global errors than their matched control group, regardless of whether there was local incongruence. In contrast, the Asperger's disorder group made a similar number of global errors as their respective control group. These results were discussed in relation to an "absence of global precedence" notion, "weak central coherence" theory, and right-hemisphere dysfunction. The neurobiological significance of these findings were discussed in the context of
a fronto-striatal model of dysfunction
10. Gillberg C et al. Autism and Asperger syndrome: coexistence with other clinical disorders. [Review] [93 refs]. Acta Psychiatrica Scandinavica 2000; 102:321-330.
Abstract: OBJECTIVE:: To provide a clinically useful analysis of the extent to which autism and Asperger syndrome coexist with other disorders. METHOD: Selective review of the literature detailing data pertaining to symptoms and disorders sometimes encountered in connection with autism or Asperger syndrome. RESULTS: A large number of medical conditions, psychiatric disorders and behavioural and motor dyscontrol symptoms are associated with autism and Asperger syndrome. CONCLUSION: Comorbidity is to be expected in autism spectrum disorders -directly or indirectly. Comorbid conditions may be markers for underlying pathophysiology and suggest a more varied treatment approach. There is a great need for in-depth research into this area, meaning that the exclusion criteria of current diagnostic manuals, i.e. those that rule out a diagnosis of autism in some disorders, and a diagnosis of certain other disorders in autism may have to be revised. [References: 93]
11. Ziatas K et al. Belief term development in children with autism, Asperger syndrome, specific language impairment, and normal development: Links to theory of mind development. Journal of Child Psychology & Psychiatry & Allied Disciplines 1998; 39:755-763.
Abstract: This study examined the relationship between the development of theory of mind and the development of the belief terms think, know, and guess. Children with autism and Asperger syndrome, matched to children with specific language impairment and normal development, completed false belief, belief term comprehension, and belief term expression tasks. The autistic group's performance on the false belief, belief term comprehension, and belief term expression tasks was significantly poorer than that of the Asperger, language impaired, and normal groups. Across groups an association was found between false belief and belief term performance. Results support a growing body of literature demonstrating links between the development of theory of mind and communicative competence. [References: 48]
12. McAlonan GM et al. Brain anatomy and sensorimotor gating in Asperger's syndrome. Brain 2002; 125:1594-1606.
Abstract: Asperger's syndrome (an autistic disorder) is characterized by stereotyped and obsessional behaviours, and pervasive abnormalities in socio-emotional and communicative behaviour. These symptoms lead to social exclusion and a significant healthcare burden; however, their neurobiological basis is poorly understood. There are few studies on brain anatomy of Asperger's syndrome, and no focal anatomical abnormality has been reliably reported from brain imaging studies of autism, although there is increasing evidence for differences in limbic circuits. These brain regions are important in sensorimotor gating, and impaired 'gating' may partly explain the failure of people with autistic disorders to inhibit repetitive thoughts and actions. Thus, we compared brain anatomy and sensorimotor gating in healthy people with Asperger's syndrome and controls. We included 21 adults with Asperger's syndrome and 24 controls. All had normal IQ and were aged 18-49 years. We studied brain anatomy using quantitative MRI, a
nd sensorimotor gating using prepulse inhibition of startle in a subset of 12 individuals with Asperger's syndrome and 14 controls, We found significant age-related differences in volume of cerebral hemispheres and caudate nuclei (controls, but not people with Asperger's syndrome, had age-related reductions in volume). Also, people with Asperger's syndrome had significantly less grey matter in fronto-striatal and cerebellar regions than controls, and widespread differences in white matter. Moreover, sensorimotor gating was significantly impaired in Asperger's syndrome. People with Asperger's syndrome most likely have generalized alterations in brain development, but this is associated with significant differences from controls in the anatomy and function of specific brain regions implicated in behaviours characterizing the disorder. We hypothesize that Asperger's syndrome is associated with abnormalities in fronto-striatal pathways resulting in defective sensorimotor gating, and consequently characteristic di
fficulties inhibiting repetitive thoughts, speech and actions. [References: 72]
13. Heaton P et al. Can children with autistic spectrum disorders perceive affect in music? An experimental investigation. Psychological Medicine 1999; 29:1405-1410.
Abstract: BACKGROUND: Children with autistic spectrum disorders typically show impairments in processing affective information within social and interpersonal domains. It has yet to be established whether such difficulties persist in the area of music; a domain which is characteristically rich in emotional content. METHODS: Fourteen children with autism and Asperger syndrome and their age and intelligence matched controls were tested for their ability to identify the affective connotations of melodies in the major or minor musical mode. They were required to match musical fragments with schematic representations of happy and sad faces. RESULTS: The groups did not differ in their ability to ascribe the musical examples to the two affective categories. CONCLUSIONS: In contrast to their performance within social and interpersonal domains, children with autistic disorders showed no deficits in processing affect in musical stimuli
14. Ghaziuddin M et al. Clumsiness in autism and Asperger syndrome: A further report. Journal of Intellectual Disability Research 1998; 42:43-48.
Abstract: Clumsiness has been proposed as a diagnostic feature of Asperger syndrome (AS), a type of pervasive developmental disorder recently introduced in the ICD-10 and DSM-IV. However, the extent to which this symptom is specific to AS is not clear. To investigate this issue, we compared a sample of AS children with age- and sex-matched groups of children with autistic disorder and pervasive developmental disorder not otherwise specified (PDDNOS). Twelve subjects with AS (ICD-10/DSM-IV; 11 males; average age 11.4 years; mean full-scale IQ 104.9) were compared with 12 subjects with autistic disorder (DSM-III-R; 11 males; average age 10.3 years; mean full-scale IQ 78.4) and 12 subjects with PDDNOS (DSM-III-R; 10 males; average age 10.1 years; mean full-scale IQ 78.2). The BruininksOseretsky test, a standardized test of motor coordination, was administered blind by the same investigator to all the three groups. While coordination deficits were found in all three groups, children with AS were found to be less impaired than those with autistic disorder and PDDNOS. However, no significant relationship was found between coordination scores and diagnosis after adjusting for the level of intelligence. These findings suggest that some patients with AS may be less clumsy than those with autistic disorder and that this difference may be the result of their higher level of intelligence. Studies based on larger samples using multiple measures of coordination are needed to further clarify the role of clumsiness in the classification of pervasive developmental disorders. [References: 25]
15. Ghaziuddin M et al. Comorbidity of Asperger syndrome: A preliminary report. Journal of Intellectual Disability Research 1998; 42:279-283.
Abstract: Asperger syndrome (AS) is a pervasive developmental disorder characterized by autistic social dysfunction and idiosyncratic interests in the presence of normal intelligence. There is no history of language delay. Although people with AS are known to suffer from comorbid psychiatric conditions, few studies have systematically addressed this topic. This preliminary report describes the occurrence of psychiatric disorders in a series of patients with AS diagnosed according to the ICD-10/DSM-IV criteria. Out of 35 patients (29 males and six females; mean age 15.1 years; mean verbal IQ 105.9; mean performance IQ 97.5; mean full-scale IQ 102.7), 23 patients (65%) presented with symptoms of an additional psychiatric disorder at the time of evaluation or during the 2-year follow-up. Children were most likely to suffer from attention deficit hyperactivity disorder, while depression was the most common diagnosis in adolescents and adults. The implications of these findings are discussed. [References: 17]
16. Gilchrist A et al. Development and current functioning in adolescents with Asperger syndrome: a comparative study. Journal of Child Psychology & Psychiatry & Allied Disciplines 2001; 42:227-240.
Abstract: Adolescents with Asperger syndrome (AS: without delay in speech development, diagnosed according to ICD-10 clinical criteria) were compared with a group with high-functioning autism (HFA: all with delayed speech development), and a group with conduct disorder (CD). Family and genetic studies suggest that Asperger syndrome and autism form part of the same spectrum, whereas the social impairments in conduct disorder are assumed to have different origins. The aims were to explore the relationships between early speech development and other aspects of functioning in autistic disorders, and to compare autistic and nonautistic social impairments. Early and current behaviour and IQ profiles were investigated. The CD group were clearly different from both the AS and HFA groups. The AS group tended to have less severe early behavioural abnormalities than the HFA group, and were unlikely to have speech abnormalities, but other communicative, social, and restricted/ stereotyped behavioural difficulties were largely of a similar pattern to the abnormalities in the HFA group. Eighty per cent of the AS group met criteria for autism on the diagnostic algorithm associated with the Autism Diagnostic Interview-Revised. By adolescence, the AS group were reported to be as abnormal as the HFA group but in structured 1:1 interaction their conversation was better. IQ profile in the AS group showed relative strength on verbal measures, unlike the HFA group, but relatively good performance on the Block Design subtest of the WISC/WAIS was a feature of both the AS and HFA groups. The results indicate closely similar behavioural manifestations may arise by adolescence despite differences in speech development. Follow-up studies and further family investigations will be required to clarify the origins of these and other patterns of autistic development
17. Fine C et al. Dissociation between 'theory of mind' and executive functions in a patient with early left amygdala damage. Brain 2001; 124:287-298.
Abstract: There have been recent suggestions that the amygdala may be involved in the development or mediation of 'theory of mind'. We report a patient, B.M., with early or congenital left amygdala damage who, by adulthood, had received the psychiatric diagnoses of schizophrenia and Asperger's syndrome. We conducted a series of experimental investigations to determine B.M.'s cognitive functioning. In line with his diagnoses, B.M. was found to be severely impaired in his ability to represent mental states. Following this, we conducted a second series of studies to determine B.M.'s executive functioning. In the literature, there have been frequent claims that theory of mind is mediated by general executive functioning. B.M. showed no indication of executive function impairment, passing 16 tests assessing his ability to inhibit dominant responses, create and maintain goal-related behaviours, and temporally sequence behaviour. The findings are discussed with reference to models regarding the role of the amygdala in the development of theory of mind and the degree of dissociation between theory of mind and executive functioning. We conclude that theory of mind is not simply a function of more general executive functions, and that executive functions can develop and function on-line, independently of theory of mind. Moreover, we conclude that the amygdala may play some role in the development of the circuitry mediating theory of mind
18. Stip E et al. Fahr's disease and Asperger's syndrome in a patient with primary hypoparathyroidism. Journal of Neurology, Neurosurgery & Psychiatry 2000; 68:115-116.
19. Fame, power, and Asperger's syndrome. Archives of Disease in Childhood 2002; 86:384.
20. Gillberg C et al. Head circumference in autism, Asperger syndrome, and ADHD: a comparative study. Developmental Medicine & Child Neurology 2002; 44:296-300.
Abstract: This study was undertaken to test the hypothesis that children with autistic spectrum disorders often have macrocephalus, and that those without comorbid learning disability are most frequently affected. Fifty consecutive children with Asperger syndrome (45 males, five females; mean age 9 years, range 1 year 6 months to 16 years) without indications of underlying medical disorders were matched for birth year and sex with 50 children (45 males, five females; mean age 6 years 4 months, range 1 year 4 months to 13 years 11 months) who met criteria for autistic disorder (a lower-functioning disorder within the autism spectrum) and with 50 children (45 males, five females; mean age 8 years 4 months, range 1 year 6 months to 15 years 5 months) who met criteria for attention-deficit-hyperactivity disorder. Birth and neuropsychiatric follow-up records were examined and data relating to occipitofrontal circumference, weight, and height were detailed. The group with Asperger syndrome included a subset of indi
viduals with macrocephalus recorded both at birth and at follow-up after the first year of life. Another subgroup developed macrocephalus during early childhood. Autistic spectrum disorders include a subgroup with macrocephalus characterized by a relatively high level of functioning and a clinical presentation most often consistent with a diagnosis of Asperger syndrome
21. Sacks O. Henry Cavendish: an early case of Asperger's syndrome? Neurology 2001; 57:1347.
22. spacing d et al. Language development and level of intelligence in autism: Does Asperger's syndrome represent a different disorder? Nervenarzt 2001; 72:535-540.
Abstract: Since the introduction of a separate diagnosis for Asperger's syndrome in the ICD-10 and DSM-IV classification systems, a controversial debate has continued on whether Asperger's syndrome is a specific, clearly distinguishable disorder within the autistic spectrum or whether it represents a milder phenotypical variation of autism. The effect on the amount of autistic symptoms of the variables language delay and level of intelligence was analyzed within a sample of individuals exhibiting autism diagnosed by standardized methods. Both variables showed a significant effect on the degree of autistic symptoms in that impairments in social interaction were less noticeable. In addition, a subsample of individuals exhibited symptoms assumed to be characteristic for Asperger's syndrome. The findings support the assumption that autism and Asperger's syndrome represent 'extreme points' on a scale of severity, which leads to the suggestion that the classification of different subtypes of autism could be abandoned in favor of a dimensional (multiaxial) approach. [References: 27]
23. Haznedar MM et al. Limbic circuitry in patients with autism spectrum disorders studied with positron emission tomography and magnetic resonance imaging. American Journal of Psychiatry 2000; 157:1994-2001.
Abstract: Objective: Cytoarchitectonic changes in the anterior cingulate cortex, hippocampus, subiculum, entorhinal cortex, amygdala, mammillary bodies, and septum were reported in a postmortem study of autism. Previously, the authors found smaller cingulate volume and decreased metabolism of the cingulate in seven autistic patients. In this study, they measured the volume and glucose metabolism of the amygdala, hippocampus, and cingulate gyrus in an expanded group of 17 patients with autism spectrum disorders (autism [N=10] or Asperger's disorder [N=7]) and 17 age- and sex-matched healthy volunteers. Method: Subjects performed a serial verbal learning test during 18F-deoxyglucose uptake. The amygdala, hippocampus, and cingulate gyrus were outlined on magnetic resonance imaging scans, volumes of the structures were applied to matching coregistered positron emission tomography scans, and three-dimensional significance probability mapping was performed. Results: Significant metabolic reductions in both the anterior and posterior cingulate gyri were visualized in the patients with autism spectrum disorders. Both Asperger's and autism patients had relative glucose hypometabolism in the anterior and posterior cingulate as confirmed by analysis of variance; regional differences were also found with three-dimensional significance probability mapping. No group differences were found in either the metabolism or the volume of the amygdala or the hippocampus. However, patients with autism spectrum disorders showed reduced volume of the right anterior cingulate gyrus, specifically in Brodmann's area 24'. Conclusions: Compared with age- and sex-matched healthy volunteers, patients with autism spectrum disorders showed significantly decreased metabolism in both the anterior and posterior cingulate gyri. [References: 30]
24. Jolliffe T et al. Linguistic processing in high-functioning adults with autism or Asperger's syndrome. Is global coherence impaired? Psychological Medicine 2000; 30:1169-1187.
Abstract: BACKGROUND: Linguistic processing was explored in normally intelligent adults with either autism or Asperger's syndrome, to test if global coherence was impaired. Global coherence is the ability to establish causal connections and interrelate local chunks into higher-order chunks so that most linguistic elements are linked together thematically. Since individuals with autism are hypothesized to have weak central coherence then one would predict that the clinical groups would have difficulty integrating information globally so as to derive full meaning. METHODS: Two experiments were designed to test global coherence. Experiment 1 investigated whether individuals on the autism spectrum condition could arrange sentences coherently. Experiment 2 investigated whether they were less able to use context to make a global inference. RESULTS: The clinical groups were less able to arrange sentences coherently and use context to make a global inference. CONCLUSIONS: The results suggest that individuals on the a
utism spectrum have impaired global coherence. Arranging sentences and making global inferences correlated highly, suggesting that central coherence may be a unitary force in these different tasks. Of the two clinical groups, the autism group had the greater deficit. The effect that such a deficit would have on one's daily life is discussed, along with possible explanations for the clinical groups' greater difficulty, and suggestions for future research
25. Mottron L et al. Local and global processing of music in high-functioning persons with autism: beyond central coherence? Journal of Child Psychology & Psychiatry & Allied Disciplines 2000; 41:1057-1065.
Abstract: A multi-modal abnormality in the integration of parts and whole has been proposed to account for a bias toward local stimuli in individuals with autism (Frith, 1989; Mottron & Belleville, 1993). In the current experiment, we examined the utility of hierarchical models in characterising musical information processing in autistic individuals. Participants were 13 high-functioning individuals with autism and 13 individuals of normal intelligence matched on chronological age, nonverbal IQ, and laterality, and without musical experience. The task consisted of same-different judgements of pairs of melodies. Differential local and global processing was assessed by manipulating the level, local or global, at which modifications occurred. No deficit was found in the two measures of global processing. In contrast, the clinical group performed better than the comparison group in the detection of change in nontransposed, contour-preserved melodies that tap local processing. These findings confirm the existence of a "local bias" in music perception in individuals with autism, but challenge the notion that it is accounted for by a deficit in global music processing. The present study suggests that enhanced processing of elementary physical properties of incoming stimuli, as found previously in the visual modality, may also exist in the auditory modality
26. Marston GM et al. Making contact - Bereavement and Asperger's syndrome. Irish Journal of Psychological Medicine 1999; 16:29-31.
Abstract: A case of abnormal bereavement is described in a man with borderline learning disability and Asperger's syndrome. Bereavement issues and concurrent assessment of psychiatric illness in people with pervasive developmental disorders are discussed. Particular reference is made to relevant psychopathology and possible underlying psychodynamic mechanisms. [References: 24]
27. Bowler DM et al. Memory illusions: false recall and recognition in adults with Asperger's syndrome. [erratum appears in J Abnorm Psychol 2001 May;110(2):215.]. Journal of Abnormal Psychology 2000; 109:663-672.
Abstract: As persons on the autistic spectrum are known not to use semantic features of word lists to aid recall, they might show diminished susceptibility to illusory memories that typically occur with lists of associated items. Alternatively, since such individuals also have poor source monitoring, they might show greater susceptibility. The authors found that adults with Asperger's syndrome (n = 10) recalled similar proportions of a nonpresented strong associate of the study list items, compared with controls (n = 15). In Experiment 2, rates of true and false recognition of study list associates did not differ significantly between Asperger (n = 10) and control (n = 10) participants. Moreover, the Asperger participants made fewer remember and more know judgments than controls for veridical but not for false recognitions. Thus, deficits found in some aspects of memory in people with Asperger's syndrome do not affect their susceptibility to memory illusions
28. Duggal HS. Mood stabilizers in Asperger's syndrome. Australian & New Zealand Journal of Psychiatry 2001; 35:390-391.
29. Nyden A et al. Neurocognitive stability in Asperger syndrome, ADHD, and reading and writing disorder: a pilot study. Developmental Medicine & Child Neurology 2001; 43:165-171.
Abstract: Boys with Asperger syndrome (n=20), attention-deficit-hyperactivity disorder (n=20), and reading and writing disorder (n=20) were followed up and retested on several neuropsychological measures 1 to 2 years after initial assessments. Wechsler Intelligence Scale for Children (WISC-III) Full Scale, Verbal, and Performance IQ scores remained stable for all diagnostic groups. Kaufman factors and 'fluid' and 'crystallized' abilities were also stable measures. Subtest stability over time, was slightly more variable. There was a tendency for the group with Asperger syndrome to deteriorate over time with respect to logical reasoning abilities. Measures of executive function/attention ('go-no-go' and 'conflict' tests) showed good test-retest stability in all diagnostic groups. This is the first study of its kind
30. Dunn W et al. Sensory processing issues associated with Asperger syndrome: a preliminary investigation. American Journal of Occupational Therapy 2002; 56:97-102.
Abstract: OBJECTIVE: The purpose of this study was to identify the sensory processing patterns of children with Asperger syndrome. METHOD: Researchers compared the performance of 42 children with Asperger syndrome and 42 children without disabilities on section and factor scores of the Sensory Profile. RESULTS: As reported by parents on the Sensory Profile, the children with Asperger syndrome were significantly different from children without disabilities on 22 of 23 items. This result was obtained with good power estimates (.997-1.00) and large effect sizes (02 = .267-.732). Both groups of children performed the same on modulation of visual input affecting emotional responses and activity level. CONCLUSION: This study provides initial evidence that clear differences exist in the sensory processing patterns of children with Asperger syndrome when compared with peers without disabilities
31. Baron-Cohen S et al. The "Reading the Mind in the Eyes" Test revised version: a study with normal adults, and adults with Asperger syndrome or high-functioning autism. Journal of Child Psychology & Psychiatry & Allied Disciplines 2001; 42:241-251.
Abstract: In 1997 in this Journal we published the "Reading the Mind in the Eyes" Test, as a measure of adult "mentalising". Whilst that test succeeded in discriminating a group of adults with Asperger syndrome (AS) or high-functioning autism (HFA) from controls, it suffered from several psychometric problems. In this paper these limitations are rectified by revising the test. The Revised Eyes Test was administered to a group of adults with AS or HFA (N = 15) and again discriminated these from a large number of normal controls (N = 239) drawn from different samples. In both the clinical and control groups the Eyes Test was inversely correlated with the Autism Spectrum Quotient (the AQ), a measure of autistic traits in adults of normal intelligence. The Revised Eyes Test has improved power to detect subtle individual differences in social sensitivity
32. Manning JT et al. The 2nd to 4th digit ratio and autism. Developmental Medicine & Child Neurology 2001; 43:160-164.
Abstract: It has been suggested that autism may arise as the result of exposure to high concentrations of prenatal testosterone. There is evidence that the ratio of the lengths of the 2nd and 4th digit (2D:4D) may be negatively correlated with prenatal testosterone. We measured 2D:4D in 95 families recruited via the National Autistic Society, UK. The sample comprised a total 72 children with autism (62 males, 10 females; age range 2 to 14 years), including 23 children (20 males, three females) with Asperger syndrome (AS), 34 siblings, 88 fathers, 88 mothers and sex- and age-matched control participants. We found that the 2D:4D ratios of children with autism, their siblings, fathers and mothers were lower than population normative values. Children with AS, who share the social and communicative symptoms of autism but have normal or even high IQ, had higher 2D:4D ratios than children with autism but lower ratios than population normative values. There were positive associations between 2D:4D ratios of children
with autism and the ratios of their relatives. Children with autism had lower than expected 2D:4D ratios and children with AS higher ratios than expected in relation to their fathers' 2D:4D ratio. It was concluded that 2D:4D ratio may be a possible marker for autism which could implicate prenatal testosterone in its aetiology
33. Howlin P et al. The diagnosis of autism and Asperger syndrome: findings from a survey of 770 families. [see comments.]. Developmental Medicine & Child Neurology 1999; 41:834-839.
Abstract: As part of a wider survey of parents of children with autistic spectrum disorders in the UK, the diagnostic experiences of 614 parents of children with autism and 156 with Asperger syndrome were compared. Although the ages of the children in the two groups were very similar at the time of the survey, parents of children given a diagnosis of Asperger syndrome had experienced significantly longer delays and greater frustration in obtaining a diagnosis than those with a child with autism. In the 'autism group' the average age when diagnosis was confirmed was around 5.5 years; in the 'Asperger group' it was 11 years. Parents of children with a diagnosis of autism were generally aware of problems in their child's development by 18 months of age; in the Asperger group concerns emerged later, at around 30 months of age. Initial worries in both groups centred around abnormal social development but parents of children with Asperger syndrome were less likely to have noted communication problems. Stereotyped or repetitive behaviours were not prominent in the early years in either group. Despite the problems inherent in data collected by postal survey, many of the findings of this study are supported by other research. The practical implications of delayed diagnosis, especially in the case of more able children with Asperger syndrome are discussed
34. Miller JN et al. The external validity of Asperger disorder: lack of evidence from the domain of neuropsychology. Journal of Abnormal Psychology 2000; 109:227-238.
Abstract: The present study compared individuals with high-functioning autism (HFA) and Asperger disorder (AD) in intellectual, motor, visuospatial, and executive function domains. Participants with AD demonstrated significantly higher Verbal and Full Scale IQ scores, significantly larger Verbal-Performance IQ discrepancies, and significantly better visual-perceptual skills than those with HFA. Once the superior intellectual abilities of the AD group were controlled (both statistically through analysis of covariance and by examining IQ-matched subgroups of HFA and AD participants), no significant group differences in motor, visuospatial, or executive functions were evident, save a marginally significant trend toward poorer fine motor performance in the AD group. This suggests that AD may simply be "high-IQ autism" and that separate names for the disorders may not be warranted. The relation of these findings to theories of autism and AD are discussed
35. Szatmari P et al. The familial aggregation of the lesser variant in biological and nonbiological relatives of PDD probands: A family history study. Journal of Child Psychology & Psychiatry & Allied Disciplines 2000; 41:579-586.
Abstract: Objective: To determine the risk of the lesser variant (or PDD-like traits) in the biological and nonbiological second- and third-degree relatives of PDD probands using a screening questionnaire and to investigate the extent to which the risk of the lesser variant differs according to various characteristics of the proband. Method: The sample consists of a series of 34 nuclear families with 2 affected PDD children (multiplex, MPX), 44 families with a single PDD child (simplex, SPX), and 14 families who adopted a PDD child. Data on characteristics of the lesser variant in 1362 biological and 337 nonbiological second- and third-degree relatives were collected from parents by telephone interview and from several maternal and paternal relatives by questionnaire. Results: All components of the lesser variant were more common in biological relatives (BR) than nonbiological relatives (NBR), confirming the familial aggregation of the traits. Proband characteristics associated with an increased risk of the lesser variant in relatives were a higher level of functioning and coming from a MPX family. Conclusions: These findings on the familial aggregation of the lesser variant suggest that the genes for PDD also confer susceptibility to the lesser variant and that PDD may be a genetically heterogeneous disorder. [References: 34]
36. Critchley HD et al. The functional neuroanatomy of social behaviour: changes in cerebral blood flow when people with autistic disorder process facial expressions. Brain 2000; 123:2203-2212.
Abstract: Although high-functioning individuals with autistic disorder (i.e. autism and Asperger syndrome) are of normal intelligence, they have life-long abnormalities in social communication and emotional behaviour. However, the biological basis of social difficulties in autism is poorly understood. Facial expressions help shape behaviour, and we investigated if high-functioning people with autistic disorder show neurobiological differences from controls when processing emotional facial expressions. We used functional MRI to investigate brain activity in nine adults with autistic disorder (mean age +/- standard deviation 37 +/- 7 years; IQ 102 +/- 15) and nine controls (27 +/- 7 years; IQ 116 +/- 10) when explicitly (consciously) and implicitly (unconsciously) processing emotional facial expressions. Subjects with autistic disorder differed significantly from controls in the activity of cerebellar, mesolimbic and temporal lobe cortical regions of the brain when processing facial expressions. Notably, they did not activate a cortical 'face area' when explicitly appraising expressions, or the left amygdala region and left cerebellum when implicitly processing emotional facial expressions. High-functioning people with autistic disorder have biological differences from controls when consciously and unconsciously processing facial emotions, and these differences are most likely to be neurodevelopmental in origin. This may account for some of the abnormalities in social behaviour associated with autism
37. Frazier JA et al. Treating a child with Asperger's disorder and comorbid bipolar disorder. American Journal of Psychiatry 2002; 159:13-21.
38. Szatmari P et al. Two-year outcome of preschool children with autism or Asperger's syndrome. [see comments.]. American Journal of Psychiatry 2000; 157:1980-1987.
Abstract: OBJECTIVE: DSM-IV specifies that Asperger's disorder is a type of pervasive developmental disorder without clinically significant cognitive or language delay. There are no data, however, on the outcome of children with Asperger's disorder or on whether their outcome differs from that of children with autism. The objectives of this study were to compare the outcome of groups of children with these disorders over a period of 2 years on variables independent of the defining criteria and to identify variables that might account for these differences. METHOD: All children 4-6 years of age who came for assessment or were currently in treatment at a pervasive developmental disorder service of one of several centers in a large geographic region were identified. Children who received a diagnosis of autism (N=46) or Asperger's syndrome (N=20) on the basis of a diagnostic interview and had an IQ in the nonretarded range were given a battery of cognitive, language, and behavioral tests. Families were contacted roughly 2 years after the date of their enrollment in the study, and many of the tests were readministered. RESULTS: Children with Asperger's syndrome had better social skills and fewer autistic symptoms 2 years after study enrollment than the children with autism. The differences in outcome could not be explained by initial differences in IQ and language abilities. Children with autism who had developed verbal fluency at follow-up were very similar to the children with Asperger's syndrome at study enrollment. CONCLUSIONS: Although the exact mechanism for the differences in outcome remain to be determined, it appears that Asperger's disorder and autism represent parallel but potentially overlapping developmental trajectories
39. Grossman JB et al. Verbal bias in recognition of facial emotions in children with Asperger syndrome. Journal of Child Psychology & Psychiatry & Allied Disciplines 2000; 41:369-379.
Abstract: Thirteen children and adolescents with diagnoses of Asperger syndrome (AS) were matched with 13 nonautistic control children on chronological age and verbal IQ. They were tested on their ability to recognize simple facial emotions, as well as facial emotions paired with matching, mismatching, or irrelevant verbal labels. There were no differences between the groups at recognizing simple emotions but the Asperger group performed significantly worse than the control group at recognizing emotions when faces were paired with mismatching words (but not with matching or irrelevant words). The results suggest that there are qualitative differences from nonclinical populations in how children with AS process facial expressions. When presented with a more demanding affective processing task, individuals with AS showed a bias towards visual-verbal over visual-affective information (i.e., words over faces). Thus, children with AS may be utilizing compensatory strategies, such as verbal mediation, to process fa
cial expressions of emotion
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Books/reports held by the BMA library:
Attwood T. Asperger's syndrome : a guide for parents and professionals. Kingsley, 1998.
BMA location: WM 203.5 [Borrow]
Videos held by the BMA library:
Autism : the lost generation. Carlton Television, 1999. 25 mins.
Asperger's Syndrome is a form of autism that affects 520,000 people in the UK with the vast majority of sufferers being male. This programme looks at the nature of autism, the importance of diagnosing it at an early age and ways of treating sufferers.
BMA location: TV 693 [Borrow]
Additional web resources:
Asperger Syndrome Coalition of the US
This is a "national nonprofit organization committed to providing the most up-to-date and comprehensive information on Asperger Syndrome and related conditions". This US site contains news, membership and volunteering information, and links to other resources. It's sections on 'Aspergers syndrome' and 'related conditions' have a number of usefully annotated citations and links including the full text of a number of peer-reviewed articles reproduced with permission from the copyright holders.
http://www.asperger.org/index_asc.html
MEDLINEplus: Autism (US)
From the National Library of Medicine, this patient information page lists latest news, links to the relevant US Institutes of Health, overviews, clinical trials, diagnosis, rehabilitation, research, specific aspects, treatment, directories, statistics and relevant organisations. A further section on children and teenagers links to the Nemours (children's) foundation site.
http://www.nlm.nih.gov/medlineplus/autism.html
National Autistic Society (NAS)
The society provides support for people in the UK with autism and Asperger's syndrome. Their site aims to provide information for those with the condition, their carers, professionals and journalists. As well as background information on autistic spectrum disorders, the site includes a search function for news; a chat facility; an email alert service; research and publications, and information about volunteering to help the NAS.
http://www.nas.org.uk/
National Institute for Neurological Disorders and Stroke (US)
The NINDS Asperger syndrome information page is aimed at carers. Clearly written, it covers diagnosis, treatment, prognosis, and research. It also lists US-based support organisations.
http://www.ninds.nih.gov/health_and_medical/disorders/asperger_doc.htm
Pervasive developmental disorder: Asperger syndrome
A topic in the e-medicine series, written by James Brasic, MD. The text is divided into 10 sections including clinical, differentials, workup, treatment, medication and follow-up. There is an extensive bibliography.
http://www.emedicine.com/ped/topic147.htm
Tony Attwood, PhD
Dr Attwood is a clinical psychologist resident in Australia who has written and spoken widely on Asperger's syndrome. His site brings together his work, and references to other resources on autistic spectrum disorders including websites, books and support groups.
http://www.tonyattwood.com.au/
Michelle Crate and Clare Aitken
15 November 2002