Asperger Syndrome : More on its Nature and its Differentiability from Autism


These notes return to the theme of specific and diagnostic characteristics of Asperger Syndrome citing recent evidence that there are distinctions between Asperger Syndrome and (high functioning) autism in respect, for example, of the associated signs and symptoms of anxiety which may be greater among Asperger samples.  The two conditions are not distinguishable in respect of varying degrees of externalising behavioural problems or motor impairments.

While it has been argued that a central feature of Asperger Syndrome is a lack of empathy, it is reported that the capacity for empathy may exist but that the recognition of the feelings of other people and, therefore, the demonstration of empathy in natural setting is limited, so that observable behaviours may give the impression of an uncaring style. 

The final section describes adaptive functioning with the conclusion that weaknesses in those skills such as communication, self-care and life skills, and socialisation, which enable individuals to adapt to day to day routines and demands, may be a central characteristic of Asperger Syndrome and out of accord with measured cognitive abilities.  


M.J.Connor                                                                                          September 2007



Asperger Syndrome versus High Functioning Autism


In the introduction to their study comparing and contrasting Asperger Syndrome (AS) and autism, Thede and Coolidge (2007) describe AS as a pervasive development disorder reflected typically in severe deficits in social interaction, restrictive and repetitive behaviours and interests, and impairments in general functioning. However, according to the DSM-IV guidelines, AS differs from autism only in that it specifically excludes cognitive and language delays.


The authors also cite converging estimates suggesting that AS has a greater prevalence (26-36 cases per 10,000 children) than autistic disorder where the prevalence may be as low as 4-5 cases according to some researchers, but as high as 16 per 10,000 according to others.


Debate still continues whether AS and high functioning autism are the same or different.  It is noted that the majority of children diagnosed with autism are not high functioning, but it is possible that this situation is artifactual in that early identification and firm diagnosis are more likely in the cases of children with severe needs. 

Individuals with AS often achieve good scores on cognitive tests, but it is the social impairments which are primary and cause them to stand out from their peers.

It is noted that Asperger’s original description of the syndrome emphasised the contrast between the apparently adequate language or cognitive skills and the marked social impairments.


Reference is made to the work of Wolff (2000) who discussed these social impairments in terms of a kind of schizoid personality disorder, and to Tonge et al

(1999) who highlighted the enhanced probability of externalising or avoidant behaviour, anxiety, and both a-social and anti-social performance when compared to individuals identified with high functioning autism.  

Nevertheless, it has still been difficult (and, presumably, a matter of some subjective judgement) to make a differential diagnosis of AS.


Meanwhile, there has been a view, first set out by Ozonoff et al (1991), that children with AS may not stand out because of language or cognitive deficits, but that this condition may be reflected in symptoms of frontal lobe dysfunction, particularly in respect of executive functioning  (planning, anticipating, organising).  It is argued that if social skills require decision-making abilities and the capacity to look ahead to outcomes, it would be very likely that AS would be marked by executive functioning deficits.

Ongoing findings concerning the differentiation of AS from high functioning autism have suggested that executive functioning weaknesses will be observable in both groups, but that deficits in theory of mind and in verbal memory appear to impact more upon the individuals with high functioning autism.


Another potential confound (or overlap) concerns Attention Deficit Hyperactivity Disorder whose symptoms and those of AS show some similarities.  Since executive function deficits are a significant part of the core features of ADHD, it would not be surprising to observe symptoms of ADHD among individuals identified with autistic spectrum disorders …. especially as both ADHD and autism are highly heritable, and have been linked to a genetic marker on chromosome 16 with implications for some shared aetiology.


Given this background, Thede and Coolidge argued that there was a need for further investigation of the co-occurrence of executive function deficits, ADHD symptoms, and other personality features within autism spectrum disorders … with a particular focus upon comparing children with AS or high functioning autism on parent-rated symptoms of psychological problems, executive deficits, and ADHD in order to identify any pattern of similarities or differences.  Whether or not impaired motor functioning could differentiate the two groups was also a question to be explored by their study.


Following approaches to parents of children formally diagnosed with autism or AS, a total of 76 families agreed to participate and completed all the ratings, with the children and young people concerned then ranging in age from 5 to 17 years.

The two measures included a 44-item survey of autistic symptoms produced by the authors, and the 200-item Coolidge Personality and Neuropsychological Inventory.

The first measure included items covering the areas of socialisation, speech, nonverbal communication, and repetitive/stereotyped behaviours.  The second involved ratings of anxiety, depression, oppositional defiance, and ADHD; plus  a scale by which to gain a picture of three areas of possible weakness in executive functioning skills – decision-making difficulties, cognitive problems (learning, memory, and language), and social inappropriateness.

Based upon the information provided by the parents, and the data contained in the initial clinical reports and diagnoses, 16 children (13 boys and 3 girls with a mean age of around 11 years) were identified as meeting the criteria for AS, and 15 (8 boys and 7 girls with a mean age of around 10 years) for high functioning autism (ie, children with language weaknesses but no reports of mental retardation).

A control group of typically developing children was recruited.


The results produced at least partial support for the Tonge et al findings that there are some distinctions between AS and high functioning autism. 

The children with AS did have higher levels of certain psychological symptomatology, notably anxiety, (and obsessiveness, depression, and avoidance).

However, unlike the previous findings, the results here did not indicate that the children with AS were more disruptive or antisocial. The two groups did not show significant differences on the scales concerned with conduct disorder or oppositional defiance.


As might have been anticipated from the existing genetic research and surveys, both target groups showed enhanced signs and symptoms of ADHD than the control group, in terms both of inattention and hyperactivity-impulsiveness.


Meanwhile, compared to controls, the two target groups were shown to have  significantly greater deficits in executive functioning, although there were no differences between the two target groups in this respect.


In the matter of motor clumsiness, reports concerning both the AS group and the high functioning autism group indicated consistent problems (in contrast to the control group); but, again, the two target groups were not differentiable.

This was taken as a counter to the argument that AS could be distinguished from high functioning autism on the basis of greater motor clumsiness.


In their summary, the authors acknowledged some limitations of their study, such as the small sample sizes, a lack of corroboration of the original diagnoses, and the predominance of one parent in completing the ratings.

Nevertheless, they felt able to highlight the difference in anxiety level as a means of distinguishing AS from high functioning autism; while also suggesting that the two groups are not distinguishable in terms of either greater disruptiveness or motor clumsiness in AS.

It was also concluded that the current results support a connection between autism spectrum disorders and executive function weaknesses and symptoms of ADHD, although AS and high functioning autism are not differentiable on such bases.


They argue that their results also run counter to any assumption that AS is a milder form of autism, and they highlight the issue of anxiety among individuals with AS and their greater awareness of problems ……. (which, one might infer, place the AS children at a considerable risk for increased psychological and emotional problems given the likelihood that they will be attending mainstream schools but, because of the social anomalies, may not be fully included; and one might also repeat the desirability of adopting a clinical approach when assessing or observing the children so that their particular profile of strengths and weaknesses can be identified as a basis for planning support.)


Empathy and Asperger Syndrome


The paper by Rogers et al (2007), concerned with empathy as a putative core characteristic of AS, begins by defining empathy as a motivating factor for unselfish and prosocial behaviour … with the converse that a lack of empathy will be associated with anti-social (or a-social ?) behaviour … and is a matter of the way in which one reacts to the observed experiences and feelings of other people.


Converging opinion or research approaches over time have suggested that empathy has two basic components. 

Cognitive empathy is defined as the process by which to gain an understanding of another person’s perspectives.

Affective empathy is defined as the observer’s (emotional) response to the feeling of another person.


A literature review completed by Rogers et al demonstrates the frequency with which deficits in empathy have been cited as a characteristic of AS (a condition marked by social impairments and restricted interests/behaviours, but differentiated from high functioning autism by the absence of significant delay in language or cognitive development). 

However, despite the proposition (Gillberg 1992) that AS and some other pervasive developmental conditions are part of a broad group of “disorders of empathy”, it is noted that there have been few attempts to measure the actual capacity for empathy among individuals with AS.


The work by Yirmiya et al (1992) could be regarded as among the first to suggest that children with high functioning autism, albeit scoring significantly more poorly than typically-developing controls, do not have a wholesale deficit in empathy and can demonstrate some empathic skills. 
(This is consistent with more recent studies of social and empathic skills which have demonstrated that such features may be less developed than in non-autistic children but that empathy and positive social behaviours are “available” albeit requiring some specific stimulus or cue by which to focus the children’s attention.  Appropriate behaviours can be elicited even if they are not automatic, although the complexity of the social and other stimuli in a natural setting, such as a playground, is such that this focus may not be feasible and the children cannot filter or organise the input and, accordingly, appear more non-responsive than is potentially the case.)


The problem identified by the present authors is that the only existing study concerned with both affective and cognitive empathy involved just two cases from which it would not be possible to draw generalisable conclusions. 

Typically, studies have not attempted to distinguish between the two components.  One such is that of Baron-Cohen and Wheelwright (2004) who reported lower empathy quotients among a sample of individuals with AS or high functioning autism, and this study highlighted a further complication in respect of distinguishing between empathy and theory of mind. 


Theory of mind refers to the ability to recognise the feelings and intentions and motivations of other people … which is very similar to the concept of cognitive empathy.  Thus, the two terms have often been used interchangeably.

The concern arises that this lack of distinction may have led to an incomplete understanding or an under-recognition of the capacity for empathy among individuals with AS.  What is seen as absent or deficient empathy may actually be a matter of limited theory of mind. 

Theory of mind may be broadly comparable with cognitive empathy, but does not encompass affective empathy. It is possible that an individual has different levels of capacity in these two components, so that an attribution of impaired empathy based upon theory of mind assessments will not do justice to the overall level of empathy that is available. 


The authors’ own study set out to explore both components of empathy, and to seek a clarification of the relationship between empathy and theory of mind.

21 adults with AS participated, following their recruitment via specialist clinics or support groups.  The diagnostic interviews were videotaped thus to be available for analysis and discussion.  Parental information on 16 of the participants was gathered via the Autism Diagnostic Interview-Revised.  Measures of general intellectual functioning were obtained (comparable to full WAIS IQs). 

A control group was recruited, matched for age, gender, educational level, and IQ. 


The participants were assessed by means of the Interpersonal Reactivity Index which covers both components of empathy.  The responses are set out in a 5-point Likert scale (from “does not describe me well” to “describes me well”). 

With regard to the cognitive component, the perspective-taking scale assesses the tendency spontaneously to share the psychological point of view of another person; and the fantasy scale assesses the tendency to identify with fictional characters drawn from books or films or plays. 

The affective component is measured by the empathic concern scale which assesses feelings of warmth and concern for other people; and by the personal distress scale which assesses how the individual is likely to react and to feel when placed him or herself in some emotionally tense situation


Also used was the Strange Stories Test where the stories contain two examples of double bluff, persuasion, irony, and white lies.  Control stories covered similar topics but are followed by questions about physical causation rather than about the thoughts and motives of the people depicted. 


The Interpersonal Reactivity Index demonstrated that, while individuals with AS scored lower than typically-developing individuals on measures of cognitive empathy, the two groups did not differ on measures of affective empathy. 

The implication that could be drawn was that AS is associated with problems in perceiving and understanding the perspectives of other people, whether real or fictional.

However, when controls were added for cognitive empathy and for theory of mind, there was no longer the trend of the AS group to produce lower scores on the affective empathy component.


The authors suggested, therefore, that individuals with AS may well have as much care and concern for other people as do typically-developing individuals.

This may be at variance with some previous findings, such as those of Baron-Cohen and Wheelwright; but is in accord with frequent anecdotal reports from parents and professionals that children with autistic difficulties can be very caring.


On the second affective scale (the Personal Distress Scale), the AS group was observed to score higher than controls … indicating a greater tendency to experience self-oriented feelings of discomfort or anxiety in response to tense interpersonal scenarios.


While acknowledging that these results may reflect the heightened levels of general anxiety commonly observed among individuals with AS, the authors held that they could equally reflect no impairment of affective empathy, even if such a capacity is not easily elicited or observed in any natural setting.

In other words, there may well be difficulty in understanding the feelings and perspectives of other people so that there is no observable response and an attribution of absent empathy; but, when given information or cues by which to increase this understanding, individuals with AS may evince as much care and concern as anybody else. 


With regard to the overlap between empathy and theory of mind, there was support for the prediction that there would be a significant and positive correlation between scores on the cognitive scales of the Interpersonal Reactivity Index and scores on the Strange Stories Test.  No such correlation was observed when it came to the affective scales.

Therefore, despite the tendency for theory of mind and empathy to be seen as largely the same, the current findings suggest that the two entities may overlap but that affective empathy seems to be at least partially independent.


Rogers et al conclude by recognising the limitations of their study, such as the small sample size and the dependence upon self report data and correlational analyses, but hold that previous reports of a lack of empathy in AS may have underestimated the affective component.

Given the social implications that may be carried by negative attributions concerning empathy, the recommendation is for continuing work on this whole issue including more multi-dimensional analyses, in order more fully to determine actual capacities and the means by which to maximise the probability of their demonstration.


Asperger Syndrome and Adaptive Behaviour      


Although AS has been included in the Diagnostic and Statistical Manual since the 1994 revision, it is argued by Lee and Park (2007) that there has been little investigation into its precise characteristics.  They regard the lack of empirical information, particularly that relating to adaptive behaviour, as underlying the continuing difficulties in making confident differential diagnoses.


The authors’ brief historical review cites the original 1944 description by Asperger of a group of children presenting with an identifiably specific style of behaviour and personality, marked by a lack of social skill and of social interaction. 

It was not until the publication by Wing (1981) of case studies highlighting its particular characteristics that AS became more widely discussed and used as a diagnostic category in its own right.

Wing described seven characteristic features of AS …..


Following the above, attempts have been made to refine the diagnostic criteria so that, for example, Gillberg and Gillberg (1989) emphasised the social impairments, narrow interests, and repetitive routines; and also noted the speech and language anomalies, poor understanding of non-verbal communication, and motor clumsiness.


DSM-IV (1994) refers to a lack of reciprocal social interaction, and to restricted and repetitive patterns of activities and interests; but no significant delay in language or cognitive development or self help and adaptive behaviour.


(One might comment that AS may be identifiable by relatively subtle features.  For example, with regard to speech and language, it may well be that the individual concerned appears to have adequate or better expressive language skills, including a good vocabulary, but there may still be problems in his or her attuning to a topic, appropriate turn-taking in a conversation, dominating the exchange and pursuing some theme without recognising the signs of impatience or uncertainty about the content on the part of the other person, etc.

It is this kind of underlying weakness, and the day to day use of existing skills, such as those involved in speech and language, that mark the individuals with AS.

One could suggest that it is the contrast between the observable or superficial “ordinariness” of many or most individuals with AS, and their significant weaknesses in areas like social and communicative skills, which interferes with their relationships and their reputations.)


In any event, Lee and Park recognise a need further to explore the precise characteristics by which AS is definable, and refer to delays or anomalies in adaptive behaviour as a potentially significant area given the frequency with which parents or professionals refer to adaptive behaviour problems but their non-inclusion in current diagnostic criteria.


Adaptive behaviour (as defined by Sparrow et al 1984) refers to the performance of day to day activities in a manner appropriate for the age group and in accordance with (social) norms and expectations. It includes communication, daily living skills, socialisation, and motor skills, all necessary for self care and independence and interaction. 


Lee and Park go on to describe how the gap between the IQ and the adaptive skills of individuals with AS can be considerable, and their review of what evidence does exist indicated that among a group of children with autistic disorder, the disparity between mental age and adaptive behaviour is greater than among children with developmental delay. 

One possible implication is that children with autistic disorder have an altered pattern of relationships between the domains of adaptive behaviour and cognitive skills. A question that follows from this is whether or not this discrepancy between intellectual ability and adaptive ability can act as a defining characteristic for AS.


Accordingly, these authors conducted a literature search for relevant studies which have appeared in peer-reviewed journals, quoted quantifiable data, used appropriate experimental methodology, and included children diagnosed with AS according to DSM-IV or ICD-10 criteria. 

Eight studies were identified, seven of which included reports of assessments using the Vineland Adaptive Behaviour Scales to determine social and personal self sufficiency.  These scales cover communication, daily living skills, socialisation, play and leisure skills, and motor skills.

 The other study cited results from the Behaviour Assessment System for Children where teachers and parents rate the children in respect of behaviours and skills in the home, community, and school.

The total number of participants in the studies ranged from 30 to 270, and the target AS individuals included in the studies ranged from 9 to 33.  The age range covered was from 5+ to 20 years.


The results and implications were grouped under several headings.


Firstly, with regard to communication, it was noted that a characteristic of individuals with AS is apparently typical language development.  However, despite the good verbal ability, it was recognised that comprehension can be very limited.

Adaptive levels for communication were reported to be adequate at best, or low, indicating that the apparently positive skills in respect of expressive language are not matched by receptive language skills.

The risk is that generally good communicative competence will be attributed or assumed, when the children and young people may actually be at a significant disadvantage.


In the case of daily living skills, as illustrated by personal and domestic skills such as dressing, hygiene, carrying out household tasks, use of leisure time, etc., the overall picture gained was of a moderately low adaptive level among the AS individuals.

This was taken as confirmation that intellectual ability does not guarantee effective daily living skills. 

Further analysis showed that the disparity between actual and predicted growth in communication and practical/personal skills tended to be small or not significant, but the development of social skills did contrast to what might have been predicted from age and IQ.


All studies that included data from the socialisation domain of the Vineland Scales reported moderately low or low levels of skill; and the study using the Behaviour Assessment System highlighted the attribution of at-risk status by the parents, but average status according to the teachers.  This disparity was attributed to the difference in settings in that, at home, there is an opportunity to observe the children in a range of activities and situations, including relatively free and unstructured settings where difficulties are more likely to arise.

The authors were able to cite additional studies which have focused upon social skills and which have reported low levels of such skills among samples of individuals with AS, including weaknesses in reading facial expressions, an understanding of informal rules of interaction, and limited (observable) empathy.

Therefore, the conclusion held that socialisation is the most challenging area for adaptive behaviours among individuals with AS. 


In respect of motor skills, there have been reports of impairments such as clumsy gross and fine movements, odd posture, immature gait, poor hand-eye coordination, and poor performance in games. A vestibular hypersensitivity has been highlighted.

Among the currently reviewed studies, only two measured motor skills. One referred to adequate performance (according to parental reports); and the other to moderately low performance (according to parent and teacher reports). 

It was concluded that the balance of evidence does suggest that motor skill impairments can provide diagnostic pointers. 


The authors accept that their study was limited by the lack of a uniform set of criteria by which AS was identified across the studies.

Nevertheless, they maintain that much of the information gleaned supports their contention that challenges in adaptive behaviour are part of the characteristics of AS with the implication that they would usefully be included within diagnostic assessments.

Future studies would usefully explore further the various domains of adaptive behaviour, and the discrepancy between cognitive ability and adaptive skills, in seeking a further clarification of the overall nature of AS and specific targeting of supportive interventions. 


                                  *          *          *          *          *          *


M.J.Connor                                                                                          September 2007





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This article is reproduced by kind permission of the author.

© Mike Connor 2007.

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