HFA and AS. Different or same? Research paper.

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Asperger Syndrome and High Functioning Autism: Research Concerns and Emerging Foci


Jan Blacher, Bonnie Kraemer, Monica Schalow
Curr Opin Psychiatry 16(5):535-542, 2003. © 2003 Lippincott Williams & Wilkins

Abstract and Introduction
Abstract
Purpose of Review: This review focuses on papers that pertain to recent work on Asperger syndrome or high functioning autism. We noted areas in which there was a preponderance of research published over the last year, including: social communication, sensory characteristics, eye gaze, neurocognitive aspects, comorbidity, and treatment and intervention studies.
Recent Findings: Children, adolescents, and even adults with Asperger syndrome/high functioning autism appear to be deficient in social skills that involve self-referencing, empathy, determination of emotions in others or inferring the thoughts of others. Some neurocognitive studies suggest that Asperger syndrome and high functioning autism are distinct disorders. A variety of social-behavioral interventions appeared in the literature, with generally positive outcomes. Comorbidity of Asperger syndrome and other psychiatric conditions (e.g. attention-deficit hyperactivity disorder or depression) continues to be identified.
Summary: Studies focusing on descriptions and specific sequelae of social deficits in Asperger syndrome/high functioning autism dominated the literature of the past year. With the decoding of the human genome it is also likely that the search for genetic pathways to Asperger syndrome/high functioning autism will continue. Finally, based on the almost total lack of information in this area, there is a clear need to develop better understanding of the experience of families raising children with high functioning autism or Asperger syndrome.

Introduction
Definitional and boundary issues are major research concerns in the area of Asperger syndrome and high functioning autism (HFA). Although Asperger first described this syndrome in 1944, it was not translated into English and widely read until 1981. Great confusion and controversy about the definition continue, with the main issue being whether or not Asperger syndrome is truly distinct from autistic disorder.

Investigators have differentiated HFA from disorders such as schizophrenia, but in such cases the definitional issues are less controversial. The overlap of diagnostic criteria for Asperger syndrome and HFA is even more difficult to untangle. Szatmari suggested that the genetic mechanism may be different for higher and lower functioning children with autism, and that there is phenotypic variation in pervasive developmental disorder. He noted, 'Is AS [Asperger syndrome] different from high functioning disorder? Yes, no, and it depends.' However, a genomewide scan in Finland suggested a possible link between chromosome 3q25-27 and a diagnosis of Asperger syndrome or infantile autism.

Nonetheless, interest in Asperger syndrome abounds, and a number of investigators have contributed in the past year to what we know about the syndrome and its implications for education, nursing practice, screening, prevalence determination and intervention. One investigator proposed that differentiation between Asperger syndrome and HFA be made on the basis of child outcomes. This review will focus primarily on papers that specifically pertain to recent work on Asperger syndrome or HFA. We will note areas in which there was a preponderance of research published over the last year, as well as those for which work was somewhat in absence.


Social Communication
Social communication deficits are central to HFA/Asperger syndrome, though they vary in extent. With regard to actual conversation skills, children with Asperger syndrome have shown more problems with pragmatic responses, and more difficulty with the emotional content of communication, even though they showed no indication of primary language impairment. In a study that involved comparison of children with HFA and Williams syndrome, the children with HFA also received lower scores on story tasks that involved emotional content. One explanation of the lack of social skills, or emotional processing, in children and adolescents with Asperger syndrome may be a problem of integrating affective and cognitive aspects of a situation. There may be a tendency on the part of Asperger syndrome youngsters to attend to parts of a social situation rather than to the whole.

In comparing children with HFA with children with either a specific language impairment or a pragmatic language impairment, the children with HFA were less skilled in inferential processing, though the pattern was similar to that of the other two language impaired groups. In another examination of social communication in children with autism spectrum disorder (ASD), Joseph, Tager-Flusberg, and Lord examined 120 children, 73 at preschool age and 47 at school age. They concluded that there appeared to be a subtype of children with autism spectrum disorder in whom verbal skills are less honed than nonverbal skills, despite the fact that the verbal-greater-than-nonverbal-subtype is most associated with Asperger syndrome.

Problems in the social behavior of adults with Asperger syndrome/HFA have also been shown, such as a lack of self-referencing or self-consciousness. Literature on adults with Asperger syndrome also suggests that they tend to be unemployed or underemployed, and suffer from loneliness and a lack of friendships.

Theory of Mind
One approach to the study of social cognition in Asperger syndrome/HFA children is through the use of theory of mind tasks. For example, investigators have reported a different or distinct 'cognitive style' in adolescents with Asperger syndrome. Using vignettes about everyday situations, the Asperger syndrome group could infer physical states in others more easily than mental states. In another theory of mind study, using tasks involving audiotaped speech segments, adults with Asperger syndrome/HFA had difficulty extracting information about the mental or emotional states of others from the vocalizations on the tapes.


Sensory, Motor, and Academic Characteristics of Asperger Syndrome/High Functioning Autism
In relation to diagnostic criteria for Asperger syndrome, Dunn and colleagues argued for inclusion of a sensory processing component. Their research has shown atypical sensory behaviors and atypical processing of sensory information in this population. For example, Dunn, Saiter, and Rinner noted that the Diagnostic and Statistical Manual of Mental Disorders-IV (text revision) does not include criteria for sensory processing deficits in Asperger syndrome, although Hans Asperger did describe these in his original paper. Moreover, Dunn, Myles, and Orr[29*] examined sensory processing patterns in both typical and Asperger syndrome children and youth. Children with Asperger syndrome showed some particular difficulties in auditory processing that reflect poor sensory modulation, despite their more normal processing of visual-perceptual information.

Motor clumsiness and postural instability have also been identified in children with Asperger syndrome. The presence and prevalence of motor impairment in a group of children with the syndrome was compared with that in a group of children classified as having a specific developmental disorder of motor function. Findings from the study by Green et al.gave credence to the co-occurrence of motor impairments and the difficulty of trying to determine distinct syndromes or subtypes.

Children with HFA/Asperger syndrome present with varied academic strengths and needs. Although it has been found that children with Asperger syndrome often enter elementary school with above average reading levels, Myles et al. reported that children with the condition had silent and independent reading levels below grade level and exhibited problems when answering inferential comprehension questions. Thus, it is critical that children with HFA/Asperger syndrome receive academic support from a very young age.


Eye Gaze
Research on the eye gaze behavior of individuals with HFA/Asperger syndrome is equivocal. Whereas some studies have indicated that individuals with these conditions spend less time viewing core features of the human face, such as the mouth and eyes, and more time viewing non-feature areas of the face (e.g. Pelphrey et al.), other studies have not supported this finding (e.g. Van der Geest et al.). Van der Geest and colleagues did find, however, that children with HFA spent equal time looking at upside-down verses upright faces, whereas control children spent less time looking at upside-down faces. This supports the notion that children with ASD have difficulty with holistic processing of the human face, and rely more on analysis of the individual elements of a face.

Goldberg and colleagues compared the ocular motor behavior of 11 adolescents with HFA with a group of age and IQ matched peers. Results indicated abnormalities in ocular motor function in the adolescents with HFA, thus providing preliminary evidence for involvement of a number of brain regions including the dorsolateral prefrontal cortex and the frontal eye fields.


Neurocognitive
Although many researchers and professionals view Asperger syndrome on the less impaired end of the autism spectrum, others have challenged this view. This alternate view is based on clinical and neurobehavioral data which support that the two are distinct disorders, as reflected in the Diagnostic and Statistical Manual of Mental Disorders-IV and International Classification of Diseases and Related Health Problems-10. In a clinical and neurobehavioral review of HFA and Asperger syndrome, Rinehart and colleagues highlight research in the areas of executive functioning, motor functioning, and lateralization that differentiate individuals with HFA and Asperger syndrome. In their review, individuals with HFA were found to have difficulty in the executive functions of set-shifting and cognitive motor response inhibition, when compared with age and IQ matched controls. This was not found in individuals with Asperger syndrome. Individuals with Asperger syndrome were often characterized as being clumsy, although the same was not true for HFA. Moreover, in a recent empirical study by Rinehart et al. HFA was associated with left hemispheric dysfunction, but Asperger syndrome was not. Rather, Asperger syndrome has been associated with right hemisphere dysfunction. Gunter et al. compared eight individuals with Asperger syndrome to eight verbal IQ and age matched controls and found that individuals with Asperger syndrome showed a pattern of visuospatial and nonverbal deficits in the presence of intact verbal processing. The Asperger syndrome individuals' memory for meaningful, complex patterns was impaired, as was their ability to understand novel metaphors and to appreciate humor.

Meyer and Minshew presented an alternate view of HFA and Asperger syndrome being distinct disorders in their review of the neurocognitive literature. After reviewing numerous studies examining cognitive and information processing, metarepresentation, and joint attention for individuals with Asperger syndrome and HFA, the authors conclude that differences which emerge between the two groups in empirical studies are often the result of cognitive ability and severity of the disorder, rather than being indicative of two separate disorders.


Brain Anatomy
Examination of the brain structure of individuals with ASD is a growing area of study. Recent articles included controlled studies comparing the brain structure of adults with Asperger syndrome with that of normal adults. Structural differences have been found between these two groups in the fronto-striatal and cerebellar regions, with individuals with Asperger syndrome having less gray matter than controls. Differences in prefrontal lobe metabolite levels have also been found between adults with Asperger syndrome and controls, with adults with the syndrome having higher concentrations of certain metabolites. Functional imaging research has shown less activation of certain areas of the brain (e.g. medial prefrontal cortex, temporal poles and superior temporal sulcus) for adults with Asperger syndrome or HFA when engaged in mentalizing tasks.[45*] Finally, post-mortem brain analyses of adults with Asperger syndrome have indicated abnormalities in the minicolumnar organization of some areas of the right hemisphere.


Comorbidity in Individuals With Asperger Syndrome/High Functioning Autism
Some suggest that comorbidity (in this case, co-occurring psychiatric conditions) is likely whenever a diagnosis of autism or Asperger syndrome is made, and that this comorbidity may be particularly stressful during periods of developmental transition. For example, although absolute figures are not available, about 40% of referrals for ASD show evidence of psychiatric symptoms. In one study, children with Asperger syndrome were reported as more likely to have attention-deficit hyperactivity disorder (ADHD), and adolescents or adults more likely to have depression. With regard to ADHD, Schatz et al. found that 62.5% of the children with Asperger syndrome received scores that were suggestive of an attention impairment or ADHD, despite the fact that the sample size was very small (eight in both the Asperger syndrome and control groups). Although not psychiatric diagnoses, there were also reported social repercussions of having Asperger syndrome, with children who have Asperger syndrome subject to victimization by peers, or objects of harsh maternal discipline - experiences likely to impact the later development of depressive symptoms.

Several case studies have documented the diagnostic and treatment history of individuals with Asperger syndrome and other co-morbid disorders. One case study describes how the proper assessment and treatment of a young man diagnosed with Asperger syndrome, bipolar disorder, and features of obsessive-compulsive disorder resulted in decreased aggression and self-injurious behavior. Obsessive behavior and restrictive interests are characteristic of individuals with Asperger syndrome, and thus make it difficult to differentiate between Asperger syndrome and other disorders characterized by obsessive-compulsive behaviors.

Asperger syndrome has also been associated with other medical conditions. Gillberg and de Souza measured the head circumference in 50 individuals with Asperger syndrome, 50 individuals with autism, and 50 individuals with ADHD to test the hypothesis that individuals with ASD often have macrocephelus. The results of this study suggested that individuals with high functioning ASD might differ from individuals that are low functioning in the type and rate of macrocephalus. The majority of children with ASD had feeding difficulties or were extremely selective with food. Previous studies have indicated that individuals with ASD are at a higher risk for being underweight or being diagnosed with a comorbid eating disorder. A recent study attempted to identify the relationship between low body weight and ASD in a sample of 103 individuals with autism or Asperger syndrome and found no significant association between domains of autistic behavior and low body weight. Hyperactivity was the only factor that significantly affected an individual's body weight. Latif used a routine blood check of 52 children with autism and 44 children with Asperger syndrome to test his hypothesis that children with ASD are at a high risk for developing an iron deficiency or anemia, possibly because of their selective eating. Results suggested that it is relatively common for children with ASD or Asperger syndrome to have an iron deficiency.


Treatment and Intervention Studies: Social-Behavioral
Children and adolescents with ASDs have abnormalities in the social arena. Indeed, instructional strategies that target social understanding and problem solving, self-understanding, and self-calming can help to prevent severe behavioral outbursts from occurring.[67*] Of late, a particular area of interest has been the social cognition of individuals with HFA/Asperger syndrome. This subgroup of children is able to engage in higher level social relationships, compared with lower functioning children with autism; however, they have difficulties with social problem solving and emotional understanding. Interventions in this area include cognitive-behavioral therapies and social skills training.

In a recent study, Bauminger examined the utility of a 7-month multifaceted cognitive-behavioral intervention on the social cognition, social behaviors and emotional understanding of 15 children with high functioning autism. Results indicated that children who received the intervention were more likely to initiate positive social interactions with peers and provide relevant solutions to social problem solving situations. They also provided more knowledge of complex emotions and had higher social skills ratings by teachers. However, in a study targeting nonverbal communication of adolescents with Asperger syndrome or a pervasive developmental disorder not otherwise specified, a social skills training program was ineffective in changing the adolescents' ability to recognize emotions in facial expressions and tone of voice. In this study training consisted of eight, 1-h sessions over the course of 8 weeks. Training during the first 4 weeks targeted paralanguage and training during the last 4 weeks focused on identifying and responding to the facial expressions of others. Although minimal nonverbal communication skill development was evident on posttest measures, the majority of the parents of the adolescents did report the development of friendships as a result of the social skills group. Thus, current research has shown some success in targeting aspects of social cognition and emotional understanding - primary areas of social difficulty in children and adolescents with HFA/Asperger syndrome.

Despite emphasis on the need to practice newly learned social skills in naturalistic contexts, few studies have examined the social behavior of children with forms of HFA in a peer context. One recent study examined the main effects of different peer groupings: children with HFA (n=9); delayed peers with autism (n=7); and typical children (n=8). Results revealed that all nine children with HFA demonstrated less solitary play and less self-stimulatory behavior during free play with typical peers, who provided frequent cues for interaction and responsiveness. The results of this study provide a compelling case for integrating young children with HFA with typical peers.

Finally, in working with children with disabilities it is critical to involve parents and other close social agents in the intervention process. Success has been shown in training parents of children with Asperger syndrome to manage their child's behavior. Sofronoff and Farbotko compared two parent training formats - a 1-day group workshop verses six individual 1-h sessions - to determine if differences emerged as a result of how parents were trained. Results indicated that, compared with a control group, both groups of parent training participants reported fewer problem behaviors and increased self-efficacy in target children at both the 4-week and 3-month follow-ups. No significant differences were found between the two intervention groups.


Psychological Well-Being of Families of Children With Asperger Syndrome/High Functioning Autism
Although researchers have paid considerable attention to the impact on the family of children with intellectual disability and autism, there is little known about parenting challenges and reactions when the child has autistic behavior but normal or near-normal intellectual functioning. One exception is a study by Schuntermann in which he proposed a clinical method that may be incorporated into child psychiatric consultations with parents of children with HFA/Asperger syndrome. Through a semi-structured family interview, parents were guided to an understanding of their child's developmental progress and to discuss child problems that may have been contributing to parental stress.


Conclusion
Studies focusing on the causes and specific sequelae of social deficits in Asperger syndrome/HFA dominated the literature of the past year. Efforts to document deficits in social processing extended to the neurocognitive realm in an attempt to better understand brain functioning. With the decoding of the human genome, it is likely that the search for genetic pathways to Asperger syndrome/HFA will continue. Finally, based on the almost total lack of information in this area, there is a clear need to develop better understanding of the experience of families raising children with Asperger syndrome or HFA.[/u]

Danke shoen. I cut and pasted this onto a MS Works doc for keeping.

Yes, this is interesting. I hope to read it more thourghly when I have time.

Thanks!

BeeBee