An integrated literature review on the adaptive behavior of individuals with Asperger syndrome.

ABSTRACT

The diagnostic definition of Asperger syndrome (AS) is surrounded by debate and controversy, because it does not address many of the broader characteristics of individuals with AS. For example, neither the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, nor the International Classification of Diseases, 10th revision, includes adaptive behavior deficits as part of the diagnosis of AS, yet many studies have reported adaptive behavior problems in people with AS. This study reviews eight empirical investigations of the adaptive behavior of individuals with AS in an effort to assess current research findings.

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SINCE ASPERGER SYNDROME (AS) WAS INCLUDED as a diagnostic category in the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV; American Psychiatric Association, 1994), and the International Classification of Diseases, 10th revision (ICD-10; World Health Organization, 1992), few investigations have been conducted to identify the characteristics of AS. The lack of empirical information--particularly as it relates to adaptive behavior--has produced controversy in terms of the diagnostic definitions and related considerations such as daily living skills, communication skills, maladaptive behaviors, or sensory issues, which can be part of adaptive behavior (Freeman, Cronin, & Candela, 2002; Klin, Pauls, Schultz, & Volkmar, 2005; Mayes & Calhoun, 2001; Ozonoff, South, & Miller, 2000; Woodbury-Smith, Klin, & Volkmar, 2005). Even though neither the DSM-IV nor the ICD-10 includes adaptive behavior issues in its criteria, many studies have identified issues in this area as being characteristic of AS (Barnhill et al., 2000; Klin, 2000; MacLean et al., 1999; Paul et al., 2005; Szatmari, Archer, Fisman, Streiner, & Wilson, 1995; Szatmari et al., 2000; Szatmari, Bryson, Boyle, Streiner, & Duku, 2003; Walker et al., 2004). To define AS more accurately, additional research related to its characteristics, including adaptive behavior, is needed. The purpose of this article is to review several studies that included data on the adaptive behavior of people with AS in an effort to assess current research findings and to reexamine the definition of AS to address the needs of individuals with AS for providing better support.

HISTORICAL REVIEW OF ASPERGER SYNDROME

"Autistic psychopathy" (Asperger, 1944, p. 76) was the first term used to describe AS. In 1944, an Austrian pediatrician, Hans Asperger, used the term to describe a group of children with a unique behavioral style, indicating a personality disorder marked by social isolation. Asperger's work was not widely known in English-speaking countries until Lorna Wing published several case studies about individuals with similar characteristics (Wing, 1981). Specifically, Wing described seven features of individuals with AS: (a) lack of empathy, naivete; (b) inappropriate, one-sided interactions; (c) little or no ability to form friendships; (d) pedantic, repetitive speech; (e) poor nonverbal communication; (f) intense absorption in certain obscure subjects; and (g) clumsy, stereotyped motor movements.

Since Asperger's (1944) and Wing's (1981) descriptions of characteristics of AS, other clinicians and researchers have proposed a number of diagnostic criteria to identify AS through classification systems including categorical approaches (Gillberg & Gillberg, 1989; Szatmari, Brenner, & Nagy, 1989; Tantam, 1988; Wing, 1981). The diagnostic criteria widely used in connection with AS are as follows:

1. Gillberg and Gillberg (1989): social impairments, narrow interests, repetitive routines, speech and language peculiarities, nonverbal communication problems, and motor clumsiness;

2. Tantam (1988): language used freely, but not adjusted to the social context or the needs of different listeners; the wish to be sociable, but failure to make relationships with peers; clumsiness; idiosyncratic but engrossing interests; and marked impairment of nonverbal communication that affects tone of voice, facial expression, gesture, gaze, and posture;

3. Szatmari et al. (1989): solitariness, impaired social interaction, impaired nonverbal communication, and odd speech;

4. DSM-IV: reciprocal social interaction and restricted, repetitive, stereotyped patterns of behavior, interests, and activities; absence of any clinically significant delay in language or cognitive development, including self-help skills, adaptive behavior, and curiosity about the environment in the first 3 years of life; and finally

5. ICD-10 criteria, which are similar to those in DSM-IV.

Currently, the DSM-IV and ICD-10 are the criteria most widely used to diagnose AS. However, as mentioned earlier, they do not include clinical delays in adaptive behavior, although both parents and professionals have noted that adaptive behavior problems present major difficulties for people with AS (Barnhill et al., 2000; Ghaziuddin & Gerstein, 1996; Manjiviona & Prior, 1995; Paul et al., 2005; Szatmari et al., 1989, 1995, 2000, 2003; Wing, 1981).

OVERVIEW OF ADAPTIVE BEHAVIOR

According to Sparrow, Balla, and Cicchetti (1984), adaptive behavior refers to the age-appropriate, typical performance of daily activities based on social standards and expectations. Thus, it includes communication, daily living skills, socialization, and motor skills necessary to perform personal and social activities. Even though the adaptive behavior problems of people with AS have been anecdotally reported, little research has been conducted in this area to date (Klin et al., 2000; McLaughlin-Cheng, 1998), primarily because the DSM-IV (American Psychiatric Association, 1994) and its successor, the DSM-IV text revision (DSM-IV-TR; American Psychiatric Association, 2000), criteria exclude difficulties in adaptive behaviors in diagnosing AS.

Wing (1981) described children with AS as lacking the ability to understand and use the unwritten rules governing social behavior. Similarly, Asperger (1944, translated by Frith, 1991) mentioned severe impairments in social integration. Moreover, many other researchers have identified…