Recognition of Autism 1 Running head: RECOGNITION OF AUTISM Early Recognition of Autism

Laboratory research on preschool-aged children with autism demonstrates consistent impairments in the domains of social behavior and communication. Other research methodologies, such as retrospective home video analysis and individual case studies, show that social and communicative deficits are evident by the end of the first year of life. This information is currently being utilized to develop appropriate screening instruments for infants. Recently, a consortium of autism researchers and professionals established a set of guidelines for the screening and diagnosis of autism spectrum disorders in early childhood. The current paper reviews research investigating the earliest manifestations of autistic symptomatology and summarizes best practices guidelines for professionals evaluating developmental disorders in infancy. Recognition of Autism 3 Early Recognition of Autism Laboratory Studies of Preschoolers with Autism During the last decade, research has elucidated the impairments associated with autism spectrum disorders in preschool aged children relative to children with developmental delay and children with typical development. Four areas of early emerging impairments are consistently observed. These are within the domains of social orienting, motor imitation (both immediate and delayed), emotional responsivity, and joint attention. Social orienting refers to a natural proclivity for typical children to orient or attend to social stimuli in their environment. For example, a child turning when his or her name is called or looking when someone enters a room. This may be contrasted with non-social orienting, such as when a child attends to stimuli not associated with social contact, like a timer beeping or a car passing. Social orienting has been studied via naturalistic observation of preschool aged children. In a paradigm developed by Dawson, Meltzoff, Osterling, Rinaldi and Brown (1998), an examiner engaged a child in play while another examiner made social sounds (clapping hands, calling the child’s name) or non-social sounds (shaking a rattle, playing a musical jack-in-the-box) from different points in the room. These interactions were videotaped and coded by blind raters for failures to orient to stimuli and the latency at which children oriented. Children with autism were compared to children with developmental delay and typically developing children. Despite poorer performance in both social and non-social stimulus categories, both orienting errors and latency were markedly higher for social stimuli among children with autism (Dawson, Meltzoff, Osterling, Rinaldi & Brown, 1998). Recognition of Autism 4 The second impairment consistently observed involves imitation in a social context. Imitation entails awareness of oneself, others, and the interpersonal interaction. It has been posited to be one of the earliest forms of social communication and a precursor to more sophisticated forms of interaction (Gopnik, Meltzoff & Kuhl, 1999). Research indicates that children with autism demonstrate impairments in both immediate and deferred imitation relative to children with developmental delay and typically developing children (Dawson, Meltzoff, Osterling & Rinaldi, 1998). The third category of consistently observed impairment is emotional responsivity, or affective responsiveness during social interactions. During social interactions in the context of a semi-structured activity, children with autism and their parents exhibit a lower percentage of reciprocal social smiling and much less smiling with prolonged eye contact compared to typical children (Dawson & Adams, 1984). Furthermore, when exposed to an examiner feigning distress, children with autism are much less likely than typical children or children with a developmental delay to attend or react to the experimenter’s expression of distress (Dawson, Meltzoff, Osterling & Rinaldi, 1998). The final category of early impairment is a constellation of social-communicative behaviors called joint attention behaviors. Joint attention behaviors are actions related to the awareness of what others are looking at or attending to and any efforts to influence others in this respect. Joint attention may be subgrouped into four different types of behaviors: following another’s gaze, pointing (protodeclarative), showing, and social referencing. Social referencing entails noticing another’s affective state or facial expression and using it as a cue to guide one’s own behavior. Social referencing is a more complex example of joint attention in that it involves orienting, attending, and Recognition of Autism 5 recognition of expression. Relative to children with developmental delay or typically developing children, children with autism show impairments in both initiating and responding to joint attention behaviors (Dawson, Meltzoff, Osterling & Rinaldi, 1998; Dawson, Meltzoff, Osterling, Rinaldi & Brown, 1998; Dawson et al., 2002; Mundy, Sigman, Ungerer & Sherman, 1986). These laboratory studies documented reliable impairments in children with autism, evident by the time they were preschool-aged, the age at which children with autism are also most commonly diagnosed. Despite this average age of diagnosis, most parents report having expressed concern to their pediatrician by the time their child turned two (Siegel, Pliner, Eschler & Elliot, 1988). Many parents report having had concerns about their child’s development prior to 18 months, and some as early as 12 months (Ornitz, Guthrie & Farley, 1977). These observations indicate that impairments in autism are unfolding before clinicians are reliably detecting and diagnosing children with autism spectrum disorders and referring them for appropriate services. Indeed, many of the impairments observed in preschool children are behaviors that are typically developmentally online by the end of the first year of life. Retrospective Home Video Analysis: Insight into the First Year of Life In order to investigate the existence of autistic symptomatology during the first 12 months of life, researchers have employed retrospective home video analysis. Osterling and Dawson (1994) compared videotapes of first birthday parties of 11 one year olds who would later be diagnosed with autism to videotapes of 11 typical one-year-olds (10 boys and one girl in each group). All children in the autism group were diagnosed with Autistic Disorder or Pervasive Developmental Disorder – Not Otherwise Specified Recognition of Autism 6 (PDD-NOS) at a multi-disciplinary clinic. Of the 11 children with autism, 9 of the children’s parents reported symptoms in the first year of life, 1 child’s parents confidently reported late onset autism (no symptoms until after 12 months), and one child’s parents tentatively reported late onset autism. A videotaped coding system was developed to code for the presence of behaviors corresponding to the impairments observed in preschoolers with autism in the laboratory studies described above. Four categories of behaviors were coded: social behavior, joint attention behavior, communicative behavior, and autistic behavior. Social behaviors included eye contact, seeking contact with an adult, and imitation. Joint attention behaviors included pointing, vague pointing, and showing. Communication behaviors included following instructions, using speech, and orienting to name. Autistic behaviors included unusual behaviors frequently observed in children with autism, specifically, self-stimulatory behavior and covering one’s ears. Videotapes were evaluated to ensure similar videotaping contexts in both groups. Groups did not differ in terms of average number of adults or children onscreen, location, or number of seconds the child was alone on screen. Coders blind to diagnoses (interrater reliability, kappa > .80) viewed tapes and coded whether or not a given behavior was present in each minute of tape. At 12 months, children with autism showed reduced frequencies of all social, communicative, and joint attention behaviors. Statistically significant differences between the autism group and the typical group were observed in terms of orienting to name, eye contact, showing, and pointing. A pediatrician experienced in the diagnosis of autism viewed the tapes and categorized children as autistic or typical based on her clinical judgment of social responsiveness, how often the child looked at faces of others, Recognition of Autism 7 and general affective tone. This resulted in 82 percent correct classification and correct identification of all but one child with autism (8 of 11 typically developing children were correctly identified). Discriminant function analysis was used to define groups empirically. Eye contact ratings alone correctly classified 77 percent of the children, and 91 percent of the children could be correctly classified based on codings of eye contact, pointing, showing, and orienting to name. Although the small number of children reported to have late onset autism prohibited statistical analysis, it is interesting to note that the child with autism whom the pediatrician incorrectly diagnosed was the child whose parents confidently reported late onset autism (Osterling & Dawson, 1994). This study demonstrated that children with autism display impairments in the domains of social, communication, and joint attention behaviors by 12 months. To evaluate the possibility that these impairments, relative to typically developing children, might be evident even earlier in development, Werner, Dawson, Osterling and Dinno (2000) used a similar paradigm to examine videotapes of children at 8-10 months. The behavioral coding system was adapted to make it more developmentally appropriate for younger children. From Osterling and Dawson’s (1994) coding system, eye contact, orienting to name, and self-stimulatory or repetitive behavior were retained. The following additional behaviors were added to the coding scheme: eye contact with smiling, three stages of babbling (vowel sounds, consonant-vowel sounds, and variegated consonant-vowel sounds), and contingent vocalizations. Both groups consisted of the same 11 children who participated in the Osterling and Dawson (1994) study with 4 additions, totaling 15 children per group. Of the 15 children in the autism group, three of the children’s parents reported late onset autism, as defined by observing no symptoms Recognition of Autism 8 until the end of the second year of life. Blind coders (kappa ranged from .68 to .91) coded all videotape taken between 8 and 10 months of age, and groups did not differ in terms of tape length, location, number of adults onscreen, or number of children onscreen. The groups differed in terms of physical setting in that the typical group had more footage taken while the child was inside a playpen (Werner, Dawson, Osterling & Dinno, 2000). When the three late onset children were excluded from the autism group, groups significantly differed in terms of orienting to name, with the autism group orienting less frequently. While the group composed of typically developing children oriented 75 percent of the time when their name was called, children with autism spectrum disorders oriented only 37 percent of the time. Percent of time with eye contact and smile was lower among children with autism relative to typical children; however, this difference was significant only at the trend level. A pediatrician viewed the tapes and categorized children based on clinical judgment. At 8-10 months, the pediatrician’s judgment was 60 percent correct (18 out of 30 overall) and was no better than chance (11 out of 15 correct for children with autism, 7 out of 15 correct for typically developing children). Viewing tapes of the same children at one year of age, she was able to identify group membership correctly 73 % of the time (22 out of 30 overall; 14 out of 15 for children with autism, 8 out of 15 for typically developing children). Through discriminant function analysis, 78 percent of the children could be correctly classified based on scores on orienting to name. It is noteworthy that children parentally identified as having late onset autism more closely resembled the typical children in the videotapes. For example, children with late onset autism responded to name calling 83 percent of the time at 8-10 months, typical Recognition of Autism 9 children responded 75 percent of the time, and children with early onset autism responded 37 percent of the time. This finding provides evidence for significant variation in the early developmental course of autism and the existence of autism with regression (Werner, Dawson, Osterling & Dinno, 2000). These retrospective home video studies demonstrated that differences in social behavior associated with autism are apparent at 8-10 months but are not as numerous or as salient as at 12 months. Furthermore, behaviors such as pointing, showing, making eye contact, and orienting to one’s name may be important diagnostic indicators in early development. These studies also showed that children with autism exhibit differences from typically developing children in the domains of social and communicative behavior within the first year of life. However, given that 80% of children with autism experience comorbid mental retardation, these results did not make clear whether these differences were attributable to autism, per se, or to more general developmental delay. Osterling, Dawson, and Munson (2002) conducted a third retrospective home video study to examine this possibility. The study compared four groups of children at 12 months of age: 6 children with autism with normal IQ (IQ > 79), 2 of which were reported to have late onset autism; 14 children with autism with cognitive delay (IQ < 70), 5 of which were reported to have late onset autism, 14 children with idiopathic developmental delay without autism, who were matched to the cognitively delayed autism group in terms of IQ and adaptive function; and 20 typically developing children. This study utilized home videos of first birthday parties and employed a coding scheme that assessed the following behaviors: looking at people, looking at held objects, looking at objects not held by other people, orienting to name, gesture, engaging in a reciprocal Recognition of Autism 10 social game, vocalizing, and repetitive motor activity. Videotapes were compared to ensure that groups did not differ in terms of tape length, amount of time child was on screen, and amount of time child was on screen alone. Groups differed in the number of children on screen; however, this factor was entered as a covariate into all analyses and was found to have no effect on dependent measures. Blind coders (all intraclass correlations > .72) viewed each tape and coded the frequency of occurrence or duration of the specified behaviors (Osterling, Dawson & Munson, 2002). Children reported to have late onset autism were excluded from between group comparisons. Both groups with autism (cognitive delay and high-functioning groups combined) and the group with developmental delay differed from typical children in terms of less use of gesture, less attention to objects held by other people, and more frequent engagement in repetitive motor behaviors. Importantly, children with autism plus cognitive delay differed from the developmental delay group in several respects; the autism plus cognitive delay group looked less at others and oriented to name less frequently than the developmental delay group. Discriminant function analysis was conducted, collapsing all the children with autism and the children without autism into two groups: autism and non-autism (developmentally delayed group and typical group, combined). Using looking at people, looking at objects held by others, and orienting to name, the discriminant function analysis correctly distinguished 85 percent of children overall (40 out of 47), with 77 percent of the infants with autism correctly classified (10 out of 13) and 88 percent of the infants without autism correctly classified (30 out of 34). Similar to the findings of Werner, Dawson, Osterling, and Dinno (2000), the late onset autism group more closely resembled the typical group in the videotapes shot at 12 Recognition of Autism 11 months, providing additional validation for the existence of autistic regression preceded by typical development during the first year of life (Osterling, Dawson & Munson, 2002). The study conducted by Osterling, Dawson & Munson (2000) indicates that the behavioral differences observed among children with autism at 12 months are independent of cognitive delay. Among the more complex social behaviors considered in these studies, such as using gesture or attending to objects held by others (primitive joint attention), there was no difference between infants with autism and infants with a nonautistic developmental delay; both groups have not yet acquired these abilities. However, children with autism differ from children with developmental delay in terms of more basic social behaviors, such as social orienting and looking at other people. These findings suggest that the earliest emerging impairments specific to autism spectrum disorders are likely to relate to looking at others and failing to orient when one’s name is called. A Case Study of a Young Infant who Developed Autism Other techniques, such as individual case studies of neonatal medical records, have provided further insight into the manifestation of autistic symptomatology in early development. Dawson, Osterling, Meltzoff, and Kuhl (2000) reported on an infant who was closely followed by professionals from birth and was diagnosed with autism at two years of age. Developmental problems first became evident within the domains of state regulation, arousal, and motor movements. Within the first six months of the child’s life, health care professionals reported poor state regulation, hypersensitivity to tactile input, hypertonia and hypotonia, oral-motor difficulties, and poorly graded movements. At 1 month, he was referred for an oral-motor evaluation by his pediatrician due to problems Recognition of Autism 12 breast-feeding. His mother reported that he varied from being excessively stiff with fisting, arching, and sensitivity, to having excessively lax muscle tone and being inactive. At 4 months, his occupational therapist reported that he was easily overstimulated, had difficulty tolerating handling well, and exhibited problems calming himself. At this time point, he was reported smiling and cooing at adults during social interactions. Difficulties in these domains of function persisted throughout the child’s development, changing slightly in manifestation as the child aged (Dawson, Osterling, Meltzoff & Kuhl, 2000). The child did not exhibit anomalies in the areas of social responsivity, prelinguistic development, and repetitive and stereotyped behaviors until 9 months of age. At this time point, the child began to exhibit poor eye contact, an absence of imitative play, and a lack of imitative babbling. At 9 months, a neurologist reported that he was hypervigilant and aware of his environment, and his eye contact seemed a “transfixed stare”. At his 12-month well baby visit, his pediatrician noted that he was socially awkward and had poor eye contact. At this time, a psychologist observed diminished social responsiveness during periods of eye contact and sporadic eye contact overall. It was reported that he would not engage in ongoing interaction, and he failed to direct vocalizations to other people. At 13 months, he met criteria for autism on the Autism Diagnostic InterviewRevised (ADI-R; Le Couteur et al., 1989; Lord et al., 1997; Lord, Rutter & Le Couteur, 1994; Lord, Storoschuk, Rutter & Pickles, 1993). At two years, he qualified for a diagnosis of Autistic Disorder on the Autism Diagnostic Observation Schedule – Generic (ADOS-G; DiLavore, Lord & Rutter, 1995; Lord, 1998; Lord et al., 1989, 2000) and displayed a schism in IQ scores with below average Recognition of Autism 13 nonverbal ability and significantly delayed verbal ability (Dawson, Osterling, Meltzoff & Kuhl, 2000). This individual case study is consistent with the previously reported findings of the retrospective home video analyses. During the first six months of life, autistic symptoms are subtle and are not particular to social behavior; these behaviors were not coded in the retrospective home video studies. These behaviors may be related to basic, subcortical brain processes. However, during the 8 to 10 month age range, problems emerged in the domains of social functioning and communication, such as poor eye contact and an absence of imitation and social prattle. These types of impairments reflect the dysfunction of more sophisticated developmental skills and are likely associated with more complex brain systems, such as emotional processing in the limbic system and higher cortical processing of language. Taken together, the findings of the home video studies and the case study suggest that the emergence of autistic symptomatology is rooted in the dysfunction of a distributed brain system or systems involving both subcortical and cortical functioning (Dawson & Lewy, 1989). These studies, however, do not clarify whether temporally subsequent dysfunction in sophisticated developmental skills represents developmental sequelae of dysfunction in more basic processes, such as the impairments evident in the first six months of life, or rather a distinct, independent neural etiology. Clinical applicability of research into early symptom manifestation Both retrospective home video analysis and the study of case histories of individual children have helped clinical professionals understand a great deal about the early appearance of autism spectrum disorders. Nevertheless, both have significant Recognition of Autism 14 limitations in terms of their direct clinical applicability. The subtle nature of the findings of many home video studies dictates pragmatic consideration in their applicability to clinical practice. In the video studies, coders examined extensive footage of tapes carefully with the aid of technological features such as slow motion and pause. Some differences, though statistically significant, were slight and differed on the order of a few percentage points. These types of group differences, though genuine and reliable, are likely to be more difficult to observe during a brief pediatric assessment, as compared to coding several hours of videotape. Furthermore, given the extreme variability in children’s behavior, even large differences might not be evident in a brief early childhood doctor’s visit. The usefulness of case study in clinical practice is limited because of the tremendous individual variability in development. A thorough understanding of the development of a single child can only provide general insight into the development of other children. For these reasons, the findings of retrospective home video analysis and case studies may best serve clinical practice by informing development of standardized assessment instruments. The impairments observed in early childhood through the use of the aforementioned research methodologies provide targets for the screening of autism spectrum disorders during early stages of development. Many researchers have used the findings of these and similar studies to develop screening instruments designed to assess children for the presence of autism spectrum disorder within the first two years of life. Recently, Filipek et al. (2000) evaluated current assessment techniques and published a set of guidelines for the screening and diagnosis of autism spectrum disorders. The authors advocate a two level approach to screening. Level One is simply routine developmental surveillance by a primary care physician performed on all children Recognition of Autism 15 at all well-child visits in order to identify children at risk for any type of atypical development. Level One screening should consist of the professionals asking about specific developmental milestones and evaluating parental concerns, as well as observing the child directly. Filipek et al. (2000) recommend several screening instruments, including the Ages and Stages Questionnaire (Bricker & Squires, 1994, 1999; Squires, Bricker & Potter, 1997), the BRIGANCE Screens (Brigance, 1986; Glascoe, 1996), the Child Development Inventories (Ireton, 1992; Ireton & Glascoe, 1995), and the Parents’ Evaluations of Developmental Status (Glascoe, 1998). The consortium identified the following red flags, or critical developmental milestones, to specifically monitor at a Level One assessment: absence of babbling or gestures by 12 months, absence of single words by 16 months, absence of spontaneous 2 word phrases by 24 months, and the loss of any language or social skills at any age. Although not specifically mentioned in this list of red flags, research in retrospective home video analysis suggests that failure to orient to name, lack of eye contact, and problems with joint attention, such as pointing and showing, would be important to assess as well (Filipek et al., 2000). Failure to meet any of these milestones indicates a greater likelihood of the presence of a developmental disability. Therefore, children who fail to meet any of these milestones should be administered additional Level One screening procedures. A laboratory assessment, including both a formal audiologic evaluation and a screening for lead poisoning, should be administered, as well as an autism-specific screening. Filipek et al. (2000) recommend several screening instruments appropriate for this purpose: the Checklist for Autism in Toddlers (designed for 18 month olds; Baron-Cohen, Allen & Gillberg, 1992; Baron-Cohen et al., 1996), the Pervasive Developmental Disorders Recognition of Autism 16 Screening Test – Stage 1 (designed for birth to 26 months; Siegel, 1998), the Australian Scale for Asperger Syndrome (designed for older, verbal children; Garnett & Attwood, 1998), and the Autism Screening Questionnaire (designed for 48 months or older; Berument, Rutter, Lord, Pickles, & Bailey, 1999). Filipek et al. (2000) recommend that children who “fail” this autism-specific screening should move on to Level Two. Level Two entails a more in-depth evaluation of children identified as at-risk and helps to provide a differential diagnosis for autism spectrum disorder versus another developmental disorder. Since the child is exhibiting delays or atypical development, the first step in Level Two is referral to an early intervention provider, such as a birth to three center for children under three years of age or an appropriate public education resource for children over the age of three. These children should also receive a formal diagnostic evaluation for autism spectrum disorder. Official diagnosis of autism should be made by an experienced clinician in concordance with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, (American Psychiatric Association, 1994) or International Classification of Disease, Tenth Edition, (World Health Organization, 1992) criteria using standardized diagnostic instruments that include both parent interview and observation. Examples of recommended parent interviews are the Gilliam Autism Rating Scale (Gilliam, 1995), The Parent Interview for Autism (Stone & Hogan, 1993), PDD Screening Test – Stage 3 (Siegel, 1998), and the ADI–R (Le Couteur et al., 1989; Lord et al., 1993, 1994, 1997). Examples of appropriate diagnostic observation instruments include the Childhood Autism Rating Scale (Schopler, Reichler & Rochen-Renner, 1998), the Screening Tool for Autism in Two Year Olds (Stone, 1998a, 1998b), and the ADOS–G (DiLavore et al., 1995; Lord, 1998; Recognition of Autism 17 Lord et al., 1989, 2000). A comprehensive cross-disciplinary evaluation should be conducted to better understand the child’s individual profile and to appropriately formulate treatment recommendations. Filipek et al. (2000) recommend that the evaluation include an expanded medical and neurological evaluation, a speech and language evaluation, a cognitive evaluation, an adaptive behavior evaluation, a sensorimotor and occupational therapy evaluation, a neuropsychological evaluation, an academic evaluation, a behavioral evaluation, and an assessment of familial functioning and resources. Additional laboratory evaluations, such as metabolic, genetic, and electrophysiological testing or neuroimaging, are indicated for particular children on a case-by-case basis. For example, electrophysiologic testing is not necessary for the diagnosis of autism but may be indicated with a history of regression or suspicion of seizure disorder (Filipek et al., 2000). The growing familiarity of these guidelines among pediatricians and the increasing availability of appropriate, reliable assessment instruments continue to augment the likelihood that pediatricians and other health professionals will be able to detect and diagnose autism earlier in development. Extant assessment instruments are providing hope for the consistent and accurate screening of children as young as 18 months; however, significant challenges remain in terms of increasing the sensitivity and specificity of these instruments and developing techniques for assessing children at younger ages. As diagnosticians continue to decrease the age at which diagnoses are applied, it will become more difficult to accurately differentiate among disorders with common features, such as autism and specific language impairment. 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