Characteristics of infantile autism: moving toward earlier detection.

Early detection of autism plays an important role in enhancing developmental outcomes for affected children. Identifying potential characteristics of the disorder evident during infancy and toddlerhood aids our efforts to screen for such symptoms, which may lead to earlier and more accurate diagnoses. This review examines the literature on detection of autistic characteristics in infants and toddlers, prior to a formal diagnosis. Findings presented derive from three methodological approaches: retrospective videotape analysis, prospective screening devices, and parent-report. Across methods, marked differences between typically developing infants and toddlers and those subsequently diagnosed with autism were evidenced in their social, affective, motor, play, and communication skills. Such congruent findings attest to the presence of specific, prediagnostic characteristics that are reliably identifiable.

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Autism is commonly noted as one of the most profound disorders of childhood. The incidence of autism is reportedly on the rise, and current estimates, reflecting this, suggest that the disorder affects between 2 children per 10,000 (American Psychiatric Association, 1994) and 20 children per 10,000 (Filipek et al., 2000). According to the Diagnostic and Statictical Manual of Mental Disorders-IV (DSM-IV; American Psychiatric Association, 1994) and Koenig, Rubin, Klin, and Volkmar (2000), affected children are characterized by abnormal or impaired development in social interaction and communication, and limited repertoires of activities or interests. They often have poor personal-attachment behaviors but may cling to a preferred object. Social skill dysfunction is one of the most salient markers of the disorder, as these children tail to establish relationships with others or to engage in joint-attention behaviors. They also tend to perform stereotyped and repetitive behaviors and may be averse to change, preferring apparently nonfunctional routines or patterns. Typically, they present with communication delays, both verbal and nonverbal, and some never develop language at all. Cognitive skills are also impaired; 75% to 80% of individuals with autism also meet the criteria for mental retardation. It has been hypothesized that these individuals focus on "dissociated fragments rather than integrated 'wholes,' leading to a fragmentary and overly concrete experience of the world" (Koenig et al., 2000, p. 302), and lack a "theory of mind," or the knowledge that individuals are mentally distinct and can have attitudes and beliefs separate from their own (Koenig et al., 2000).

For a clinical diagnosis of autism, these characteristics must present prior to 3 years of age; however, in some cases, a period of apparently normal development precedes atypical functioning. Usually, children are not diagnosed with autism until age 3 or later, likely because it is difficult to distinguish between autism and other childhood disorders, such as developmental delays and mental retardation. In addition, there appears to be a "relative lack of available professional expertise and provision [of services]" (Smith, Chung, & Vostanis, 1994, p. 552) for this population. However, because many parents of children who were later diagnosed with autism reported concerns about their children's atypical development during infancy, researchers have begun to explore the possibility and validity of detection prior to age 3.

Value of Early Detection and Diagnosis

The importance of early detection of autism is twofold. First, children who are accurately diagnosed will have immediate access to intervention services. Because DSM-IV diagnoses often are not made until 3 years of age or later, affected infants and toddlers are missing out on immediate therapeutic options. According to Rogers (1998), children with autism who are treated early exhibit significant improvements in functioning relative to older children with autism undergoing the same interventions. Thus, early detection of autism that leads to early intervention seems key to improving develop- mental outcomes for these children.

Second, being the parent of a child with a disability can be frustrating, particularly if parents suspect something is wrong but cannot find any help or answers. It is difficult to care for and connect with a child who avoids eye contact, ignores socialization attempts, and does not communicate. Additionally, some parents have experienced frustration in trying to get a diagnosis and services from professionals, asserting that specialists dismiss their opinions and concerns about their children (Schall, 2000). As Goddard, Lehr, and Lapadat (2000) stated, "[Parents] described a system that compartmentalized, that regularized, and that fostered fear, confusion, and frustration. Within this overriding system, problems of coping with disability emerged" (p. 283). Parents need accurate information about their children's difficulties so that they can learn how to best care for and manage them, as well as a relationship with a sensitive and knowledgeable team of providers that responds to their concerns. Earlier detection may mitigate long-term familial stress over the uncertainty of what is affecting their child. With a diagnosis, parents can become educated about autistic disorders, make informed decisions on best-care practices for their children, and move in an appropriately therapeutic direction.

Research on Autism Spectrum Traits in Infancy

At its meeting in 1998, the National Institutes of Health Autism Coordinating Committee explored the status of research in the field of autism and outlined the areas of highest priority for continued research efforts. While the search for a causal mechanism topped the fist, improvements in diagnostic capabilities, particularly with infants and toddlers, came in at a close second (Bristol-Power & Spinella, 1999). In support of this focus on detecting autism during infancy, the National Institute of Mental Health (NIMH) advertises a list of behavioral differences indicative of infants at risk for developing autism. The behavioral cues suggestive of autism are contrasted, point for point, with the behaviors of typical infants. For example, typically developing infants are described as "easily stimulated by sound" and "using [their] bodies purposefully to reach or acquire objects," while those at risk for autism "seem deaf" and "practice strange actions like rocking or hand-flapping" (NIMH, 1997).

On his Web site providing an overview of autism, Edelson (1999) states, "Many infants with autism are different from birth" (p. 1). They commonly evade physical contact by arching their backs away from caregivers and fail to anticipate …