by

Linda R. WATSON, Elizabeth LANTER,
Cara McCOMISH, Vicky POSTON ROY*
The University of North Carolina at Chapel Hill, USA

Abstract
Research and professional development efforts over recent years have resulted in an increase in the number of children who are diagnosed with autism spectrum disorders prior to the age of three years. Clinicians have access to a larger body of evidence describing the characteristics of young children with autism, but a relatively limited body of direct evidence regarding the most effective interventions for these children. In this article we focus on evidence that is relevant to efforts to improve the communicative functioning of young children with autism with due consideration given to the developmental needs of toddlers as well as the needs of their caregivers.

Key words: autism spectrum disorders, communication, early intervention, toddlers

New screening and diagnostic tools designed for very young children have increased the likelihood that children will be diagnosed with autism spectrum disorders (ASD) during the toddler period, or under the age of three years. Research on the diagnosis of children under age 3 years has included investigations with the Checklist for Autism in Toddlers (CHAT; Baron Cohen, Allen & Gillberg, 1992; Baird et al., 2000), the Autism Diagnostic Observation Schedules (Lord et al., 2000), the Autism Diagnostic Interview-Revised (Rutter, LeCouteur & Lord, 2003), the Modified CHAT (MCHAT; Robins et al., 2001), and the Screening Tool for Autism in Two-Year-Olds (Stone, Coolrod & Ousley, 2000), among others. Earlier diagnoses offer hope for earlier intervention that may lead to significant developmental impacts, but research on appropriate or effective intervention strategies for toddlers with autism spectrum disorders is limited to date. Although we recognize the multifaceted needs of toddlers with ASD, our specific aim in this article is to assist clinicians in enhancing the communication development of these children.
 We structure our discussion around four main topics related to toddlers with ASD: (1) the developmental phenomena of the toddler years that have been associated with later language and communication outcomes; (2) assessment tools and strategies to use in developing an individualized intervention plan; (3) intervention strategies to improve communication outcomes; and (4) collaboration with families.

Predicting Communication Development Outcomes in Toddlers with ASD

 Given the limited amount of direct research on effective interventions to promote the communication development of very young children with ASD, we propose that clinicians use indirect evidence regarding factors that influence developmental outcomes to guide intervention planning for these children. By the time they are 18 to 24 months of age, toddlers with ASD exhibit marked deficits in many aspects of social and communication skills, including imitation of others’ behaviors, orienting to people who speak to them, functional and symbolic play, social engagement with others, using gestures or words for communicative purposes, directing varied facial expressions to others, responding to bids for joint attention to an object or event by such means as following another person’s direction of gaze, pointing, or verbal cues, and initiating bids for joint attention by such means as verbally commenting, pointing, and shifting gaze between a communicative partner and the object or event of interest (Baird et al., 2000; Baranek, 1999; Charman et al., 2001; Maestro et al., 2002; Neitzel et al., 2003; Osterling, Dawson & Munson, 2002; Watson et al., 2000; Wimpory et al., 2000). The early interventionist needs knowledge beyond a listing of the deficits of toddlers with ASD, however, in order to develop guiding principles for intervention goals and strategies.
 Chapman (1978), in seminal work, proposed that by 9 months of age, infants are using a variety of nonverbal strategies to meet the challenge of determining what other people mean when they speak. The nonverbal strategies Chapman proposes as important to infants and toddlers between the ages of 9 and 24 months include: looking where other people look (gaze-following); giving evidence of notice (joint attention); imitating other’s actions; and doing what you usually do with an object (functional play). These are the key aspects of nonverbal behavior that typically support the toddler’s progress in mapping of language onto real world objects and events, but they are areas that are problematic for young children with autism.
 There is growing evidence that the degree of impairment experienced by young children with ASD in most of these areas is predictive of later developmental outcomes; this is especially true in the area of language development. For example, Sigman and Ruskin (1999) found that among children with autism, the degree to which the children responded to bids for joint attention as preschoolers was positively related to their growth in expressive language skills nine years later. In addition, the number of different functional play acts the children exhibited as preschoolers predicted their expressive language gains at follow-up. In each case, these associations were significant even after controlling for the children’s language level as preschoolers. Together the two preschool measures of nonverbal behavior accounted for 43% of the variance in expressive language gains at follow-up. Interestingly, the extent to which preschool children with autism initiated joint attention as well as their functional and symbolic play skills were related to their success in engaging socially with their peers at the       9-year follow-up.
 In other research, the imitation skills of young children with autism have been related to later language outcomes. Stone and colleagues (Stone, Ousley & Littleford, 1997; Stone & Yoder, 2001) examined the imitation abilities of                   2-year-olds who were diagnosed with autism, and then completed follow-up evaluations of the children’s language skills 1 to 2 years later. Toddler imitation skills, especially the ability to imitate body movements (as contrasted to actions on objects), were positively associated with later expressive language scores, after controlling for initial language levels.
 The ability of toddlers with autism to initiate joint attention with adults has also been associated with later language outcomes. Charman et al., (2003) observed the extent to which 20-month-old children with ASD switched gaze between an adult and each of a series of mechanical toys that were selected for their potential to both attract attention and provoke feelings of uncertainty in the children. The toddlers with ASD who demonstrated relatively high levels of joint attention initiation at 20 months had higher expressive and receptive language scores at 42 months than those children who demonstrated relatively low levels of joint attention initiation. Other research indicates that early intentional communication for the purpose of requesting is also related to later language outcomes for children with ASDs (Sigman & Ruskin, 1999; McDuffie, 2004). This type of communication also generally involves coordination of attention between a desired object or action and a communicative partner, although with a different end goal than in joint attention initiation. McDuffie’s research indicated that early joint attention and requesting behaviors make unique contributions to predicting language outcomes for young children with autism.
  The collective evidence from longitudinal investigations of young children with ASD, then, supports the idea that the nonverbal comprehension strategies suggested by Chapman (1978) are important not only for toddlers to solve the immediate challenge of determining what people mean by what they say, but also in enhancing language development across time. In addition, research suggests that the more a toddler with ASD expresses nonverbal communicative intents, both in requesting and in initiating joint attention, the better later language outcomes are likely to be. These findings are important complements to the limited intervention research on toddlers with ASD, in that they suggest imitation, object play, and initiating and responding to joint attention, and overall increases in intentional communicative acts should each be addressed in programs designed to improve the communication outcomes of toddlers with ASD.
 Our intervention design can also benefit from examining the available evidence related to influences on communicative development that are more external to the child. The nature of caregiver-child interaction is an important consideration, but the impact of the quality of interaction on communication outcomes in this population has received limited attention to date. Two studies (Leekam, Hunnisett & Moore, 1998; Doussard-Roosevelt et al., 2003) have suggested that when caregivers use more perceptually salient cues (e.g., pointing and saying “Look” in conjunction with gazing at an object; being in physical proximity to the child; manipulating objects) to supplement their verbal initiations, young children with ASD are more likely to respond. Only one study to date has examined the impact of interaction strategies on language development in children with ASD across time. Siller and Sigman (2002) reported that the extent to which parents of preschoolers with autism talked about their child’s current focus of interest without directing the child’s behavior was positively associated with language outcomes 10 and 16 years later. Furthermore, the correlations between the early parent interaction strategies and later child language outcomes were quite high (.67 and .79 at 10- and 16-year follow-ups, respectively), suggesting the importance of further research in this area as well as the importance of addressing parent-child interactions as a component of early intervention for toddlers with ASD.
 In summary, the available literature on young, mostly preverbal children with ASD suggests there are several variables related to facets of the child’s development as well as caregiver-child interaction variables that relate to the child’s developing language and communicative abilities. These include the child’s development of play and imitation skills, following of attention cues provided by others, and the child’s own preverbal intentional communication, as well as the tendency of caregivers to use perceptually salient cues, and to comment in a nondemanding way on the objects and events that engage the child’s interest. In the remainder of this article, we will use this background information as a framework for describing assessment and intervention strategies appropriate for toddlers with ASD. In addition, due to the important role of parents and other caregivers in the development of young children with ASD, we will address the sources of stress and needs for support for families of these children.
Communication Assessment

The ultimate purpose of a comprehensive communication assessment is to develop a communicative intervention plan (Marcus & Stone, 1993). Gillingham (2000), a well-respected teacher of individuals with ASD, suggests that the professionals’ role is not to “teach” communication but to “find it”. Regarding children with autism, Gillingham says, “They may not be using words. Their gestures may not exactly match ours. Their behavior may appear ‘inappropriate.’ All of this is communication. If and when we take the time and make the effort to observe and to listen, we can and will understand (p. 111).” The communicative assessment should, thus, provide careful and systematic attention to the characteristics of the environment and interactive partners that help produce or facilitate communicative acts; the goal being to “find” what motivates the child to communicate and how s/he communicates, in order to support the child and family in expanding on current interests and abilities (Peck, 1989).
The communication assessment should include analysis of not only the affected child, but also the social contexts between the child and primary caretakers (Warren, Yoder, & Leew, 2002). This will require the examiner to understand the crucial role of families in the assessment and intervention process for toddlers, consider his or her own beliefs about families and disability, and encompass the competencies to assess the child’s social-communicative understanding, communication means, communication functions, and play behaviors (Wetherby, Prizant, & Schuler, 2000). The professional evaluating and/or treating the child with an ASD and their family may find it helpful to reflect and self-evaluate their own attitudes and beliefs concerning child development and the role of families, as the children’s ultimate success is contingent on not only their own abilities, but also the ability of the adults in their lives to facilitate their growth (Kluth, 2004). This introspection may later be used to help families of children with autism adapt their style to best meet the needs of their child, an important professional purpose as parents are often less aware of the centrality of language comprehension compared to expressive language abilities, or assume that their child understands what they say (Marcus & Stone, 1993).
The role of families in both the assessment and intervention process has received increased attention in recent years. Contrary to earlier beliefs that autism was caused by parental rejection, lack of love, or inadequate parenting skills (Janzen, 1999), today it is understood that the parents or primary caretaker(s) of children affected by ASD are the focal points to promote and enhance the development of social communication (Warren et al., 2002). It is therefore essential that they not only be directly involved in the evaluation process as providers of information, but also considered the most important recipients of the evaluation results and interpretation (Marcus & Schopler, 1987).
With the goal being to acquire the knowledge necessary to construct an intervention plan, the assessment should, specifically:
 determine the child’s communication means (e.g., use of gestures, sounds, or words)
 assess the range and frequency of communicative functions or purposes for communicating, such as behavior regulation or joint attention (Wetherby et al., 2000)
 observe the contexts and conditions which appear to promote the best attention or comprehension by the child, including the caretaker’s ability to evaluate communicative effectiveness, and when necessary, fix or repair failing communicative attempts to improve their child’s understanding (Prizant & Schuler, 1987), and
 assess the child’s typical play behaviors (Wolfberg & Schuler, 1999). These components are detailed further below.
An assessment of communication means should include: children’s ability to use social/affective signaling, their ability to use gaze shifts between the person and object, their expression of positive affect with directed eye gaze, and episodes of negative affect; conventional communicative forms such as conventional gestures (e.g. giving, showing, pointing, reaching), use of distal gestures (e.g. pointing at a distance), coordination of gestures and vocalizations; vocalizations, with and without gestures, and word use (Wetherby et al., 2000), sign, or other augmentative communication (Quill, 1995), and nonstandard communication means which may include behaviors such as tantrums and running, and/or echolalia (Quill, 1995).
Communication functions are often rooted in intent (Quill, 1995); as such, communicative intent needs to be considered in relation to the function of communication (Wetherby & Prizant, 1989). Three broad categories of communicative functions that are applicable to both preverbal and early verbal communications of young children are social interaction, behavior regulation, and joint attention. Although communicating for behavior regulation functions appears to be a relative strength compared to joint attention functions for preschool-age and older children with ASD, research in our laboratory and elsewhere suggests that gesturing for the purposes of behavior regulation and joint attention are both relatively rare in toddlers with ASD, whereas gesturing for the purpose of social interactions is more commonly observed (Neitzel, et al., 2003; DiLavore & Lord, 1995). Thus, in individualized assessment and planning for the toddler with ASD, it is important to examine the use (or nonuse) of communication for each of these three broad categories.
It is critical that the examiner identify the conditions under which the child consistently responds to others’ communication and how the caretaker may modify the situation to increase the child’s understanding; this will help the evaluator to make recommendations on how parents and other caregivers could modify their communicative input to the child to enhance attention and comprehension processes (Quill, 1995). For example, was the child’s response differentially affected when the adult did any of the following: spoke more slowly, used shorter sentences, repeated certain words, used expressive gestures, provided motivation for the toddler (e.g. caretaker provides two choices including the child’s favorite toy train and a doll the child routinely disregards), or used communication in a routine context (e.g. “Time for lunch,” when the child could see or smell food being prepared). In general, toddlers are better at understanding adults’ intentions than they are at understanding the specific words, and this may be especially apparent in assessing children with autism (Carpenter, Pennington, & Rogers, 2001).
Finally, another area to consider during the assessment process is object play behaviors. Both expressive language and symbolic play are considered forms of representational or symbolic behavior. Earlier forms of object play also may be important foundations for language development. If, for instance, a child engages in play with a variety of objects, and if the parent frequently talks to the child about the child’s focus of attention (as was the case in research by Watson, 1998), then the child’s play behavior will afford the parent with opportunities to model a broader diversity of vocabulary in talking to the child, in a context that appears to enhance the language development of children with autism (Siller & Sigman, 2002). In addition, functional play, or playing with objects in conventional ways, provides a basis for the child to make predictions about what other people are likely to be saying when they communicate about a particular object (Chapman, 1978). The evaluator should document the child’s number of different action schemes (e.g., rolling a ball, putting blocks into a box, spinning the wheels on a toy car), as well as the complexity of action schemes in symbolic play (e.g., a one step scheme might involve putting a doll to bed, whereas a two step scheme might involve feeding a doll and then putting the doll to bed), and their level of constructive play (Wetherby et al., 2002).
Evaluating language structures such as syntax and morphology, which are routinely found on standardized language tests, are not a priority for children with ASD; they are not sensitive to the extent to which an individual with ASD, especially one of toddler age, is able to communicate effectively with relevant others in his or her everyday social environment (Schuler et al., 1989). Any standardized language measure should be interpreted with caution as individuals with ASD struggle with the acquisition of communicative skills more than language abilities per se (Paul, 1995); even when language is acquired, children with ASD are challenged in the effective use of language as a social tool to communicate (Wetherby & Prizant, 1989).
For this reason, several types of informal, qualitative analyses should be utilized to assess the child’s communication abilities in everyday interactions. An interview with the primary caretaker(s) to discover the child’s communicative means and functions is an important piece of the assessment. In addition, a communication sample, elicited during several of the child’s typical activities, will assist in quantitatively documenting their self-initiated as well as responsive communication means and functions. Other important informal assessments include: a qualitative analysis of the factors that appear to affect language comprehension; as well as observations of the interactions between the child and the primary caregivers to help identify the features of the adult’s communication style that enhance the child’s communicative competence and to help identify needed modifications in the adult’s style (Quill, 1995). It is essential that some measures reflect the toddler’s abilities in the natural social context, the true demonstration of communicative competence (Schuler et al., 1989). These measures can be obtained from informally created protocols and/or standardized social-communication scales. These types of assessment tools are discussed below.

Caregiver interview
The caregiver interview can be used to evaluate communicative behaviors at the prelinguistic level and provide input pertinent to the development of an instruction program (Schuler et al., 1989), as well as document the child’s range of communicative behaviors and purposes for communicating (Wetherby & Prizant, 1989). Parents, therefore, need to have an active role in the communication assessment (Marcus & Stone, 1993). This includes working closely with the evaluator toward accomplishing a variety of goals such as: developing an accurate picture of child’s communication ability, identifying strategies for simplifying and modifying linguistic and social-communicative behaviors that increase the child’s responsiveness, identifying regularly occurring routines within the home, and identifying the types and amount of information and or training needed by caregivers to enhance communication (Prizant & Wetherby, 1993).

Caregiver-child observation
In a caregiver-child observation, the evaluator is observing how the child communicates with a familiar caregiver, and how the caregiver responds to the child. Although the caregiver interview will identify the types of communicative functions used by the child, caregivers may interpret their child’s reaching behavior as a request, whereas the evaluator may observe that the child does not show clear awareness of the adult as a communicative partner rather than just a means to an end (Wetherby & Prizant, 1989). Adults also may use a variety of strategies such as gesturing, demonstrating their meaning through actions on objects or the child, using specific intonation patterns or signals to get the child’s attention repetition, and talking about objects and actions on which the child’s attention is already focused. Faced with communicative breakdowns, the adult may question, rephrase and add or change communication cues. Caregivers will vary in the extent to which they talk about the child’s current interests (Watson, 1998), and the findings of Siller and Sigman (2002) suggest that parents who do little of such “following-in” to the child’s interests might have a more positive impact on their children’s language development if they adopt more responsive interaction strategies. Parents who are already highly responsive to their children’s interest, however, do not need an intervention approach that includes coaching on these types of interaction strategies. Thus, it is critical to evaluate the strategies used spontaneously by caregivers, as well as their effectiveness in engaging or maintaining the child’s engagement in a communicative interaction, before creating an intervention plan (Peck, 1989).

Communication Sampling
The communication sample is used as an attempt to collect a representation of the child’s communicative behavior. We recommend that the sample be ongoing, not episodic, and that it should dynamically explore situational contexts to facilitate or entice the child to participate in communicative interactions (e.g., does the child initiate communication if you blow bubbles and then screw the lid tightly on the bubbles and hand it to the child?) (Wetherby & Prizant, 1989). Qualitative and quantitative analyses of the child’s means and functions is necessary for intervention planning as the functions used least often and/or those functions that are absent should be those targeted in the intervention plan (Quill, 1995). Toddlers with ASD usually need to increase both the number and diversity of effective and intentional communicative means and functions, but the specific needs of the individual child can be determined only through careful assessment.

Norm-referenced measures
Formal measures are available to assess the skills discussed above. Available normative data will not be applicable to children in cultures outside of the United States, but due to the focus of these measures on nonverbal and early verbal behaviors, they have utility for structuring the assessment of toddlers with ASD across different cultures. Once a child has begun to use some intentional communication, but before they begin to talk, The Communication and Symbolic Behavior Scales (CSBS; Wetherby & Prizant, 2002), a tool specifically designed to measure the social-communicative abilities of young children with ASD, or The Early Social-Communicative Scales (ESCS, Siebert, Hogan, & Mundy, 1982) can be used to analyze the child’s communicative means, functions, and repairs. The MacArthur Communicative Development Inventory (Fenson et al., 1993) is a parent report measure that can be used to assess communicative gestures, some symbolic play skills, and lexical knowledge.
The communication intervention program should be developed from these assessment results. It is important that the intervention program be fully individualized, based on the child’s profile of communicative, social/affective, and symbolic abilities. The intervention plan should also include the family’s priorities, resources, and needs (Wetherby, Prizant, & Hutchinson, 1998).              Short-term goals may include: helping the child to participate in interactive or turn-taking routines, establishing a clear intentional signaling system, developing socially appropriate and conventionalized signals, and increasing the variety and frequency of communicative intentions (Westby, 1998).

Early Intervention for Children with Autism

With the recent emphasis in the literature to identify early diagnostic criteria for children with autism, evidence suggests that earlier intervention stands to benefit the child with autism to a much greater extent than intervention beginning after children are five years of age. Researchers and clinicians are advocating for early, intensive intervention for children with a label of autism (Woods & Wetherby, 2003). This emphasis is based on research indicating that children who receive early intervention before three years of age are more likely to demonstrate greater gains in language and communication development than children who receive intervention later in life (Chandler et al., 2002). In addition, research has found a significant amount of variability among children with autism suggesting that a diagnosis of autism in and of itself does not necessarily predict later developmental outcomes (Sigman & Ruskin, 1999). Given the potential for significant gains for children with autism, early intervention is critical.
Although there is limited research available examining the efficacy of intervention with children with autism younger than three years of age, there is empirical support for the benefits of early, intensive therapy for children with other developmental disabilities including mental retardation and Down syndrome (McCathren, 2000; Warren et al., 1993; Yoder & Warren, 2002) as well as theoretical support for the efficacy of early intervention for children with autism (Mundy & Neal, 2001; Ozonoff & South, 2001). Theoretical support is based in part on research examining the efficacy of intervention for older children with autism. Additionally, research identifying relationships between early nonverbal communication skills including gesture use (Carpenter, Nagell, & Tomasello, 1998), joint attention (Markus et al., 2000), and early representational play (Sigman & Ruskin, 1999) with later language abilities suggest potential benefits of early intervention focusing on improving these early communication and play skills in children with autism.
The earliest intervention models were primarily behavioral in nature and focused on mass discrete trial methods (Lovaas, 1977). The idea behind these types of therapies was that children with autism could not benefit from teaching that occurred in their natural environments due to significant difficulties with attention and learning abilities (Prizant, Wetherby, & Rydell, 2000). Unfortunately, early behavioral methods that focused on discrete trial training often resulted in limited generalization. Children with autism who were involved in this type of therapy became passive recipients of communication primarily acting as responders to the communication initiations of others. In an effort to acknowledge the weaknesses of this type of strict behavioral approach, researchers began to search for more naturalistic methods of intervention for children with autism. This has led to the recent shift over the last two decades regarding the conceptualization of intervention for children with autism. This movement resulted in a focus on more naturalistic approaches that consider social interactions as critical to learning language and communication. In this type of model, children take on a more active role in the learning process as opposed to the earlier emphasis on children with autism as passive recipients of language.
Two programs that are described in the current literature and designed primarily for toddlers with ASD illustrate this shift in approach. The intervention models of these two programs were distinctly different from one another in several respects, and yet both incorporate more naturalistic approaches that engage the child in social interactions as a context for promoting the acquisition of targeted skills. In the Walden Toddler Program, McGee, Morrier and Daly (1999) enrolled toddlers with ASD in a center-based program for 3.5 hours per day, 5 days per week. Each classroom served 4 toddlers with ASD and 8 children who were typically developing. In addition, a family program supplemented the classroom intervention with up to 4 hours per week of intervention demonstration in the home with parents required to commit to providing a minimum of 10 additional hours of home-based instruction to their child each week. An interdisciplinary team provided input to the program goals for toddlers with ASD. These included goals for increasing expressive verbal language, engagement with toys, social responsiveness to adults, social tolerance and imitation of peers, and independence in daily living. Classroom teachers were taught to embed incidental teaching activities in naturally occurring activities, to supplement incidental teaching with one-to-one instruction when the child has limited opportunities to learn a skill in naturally occurring activities, to use the child’s preferred toys and activities to increase motivation, and to systematically rotate toys in order to maintain novelty and match toys to current goals. In addition, the classroom staff learned specific strategies for creating incidental learning opportunities, shaping behavior, actively teaching appropriate social engagement with peers, and promoting ongoing engagement with classroom activities and toys.
 The outcomes reported by McGee et al. (1999) are based on 28 children with autism who participated in the intervention program for at least 6 months. At program entry (mean age of 29 months), 36% of the children used verbalizations, although it was reported that much of the language used was echolalic or perseverative. At the time of exit from the program (mean age of 41 months) 82% of the children were using meaningful verbal language. The other outcome measure related to peer proximity. Twenty of 28 children showed improvements in measures of peer proximity from the time of program entry to the time of program exit with 7 additional children exhibiting acceptable peer proximity at the time of program entry (i.e., comparable to peers without disabilities) with levels of peer proximity being maintained over the course of the children’s enrollment.
 Mahoney and Perales (2003) reported on intervention outcomes for 20 young children with ASD (80% of whom were under three years of age at enrollment). The authors categorized their program as “relationship-focused” intervention. Specifically, parents and children met individually with early intervention specialists for 1 hour per week, either in a center-based setting or in the child’s home. On average, families participated in 31 individual sessions spanning an average time period of 11 months. The intervention objectives were selected based on an individualized assessment of the child and family. Objectives for the child were drawn from the areas of cognition (e.g., social play, initiation, problem solving), communication (joint activity, joint attention, vocalization, intentional communication, conversation), social-emotional functioning (e.g., attachment, empathy, self-regulation), and motivation (e.g., interest, persistence, enjoyment). Parents learned responsive teaching strategies to incorporate into interactions with their children during daily routines. The strategies included five components: reciprocity, contingency, shared control, affect, and match.
 Comparison of pre-intervention to post-intervention measures revealed significant changes in parent behaviors related to responsive teaching as well as child behaviors related to social interaction (including joint attention), temperament, and social-emotional functioning (Mahoney & Perales, 2003). Further, although the parents’ initial level of responsiveness was not significantly associated with gains in their children’s social interactive functioning across the intervention period, the changes in parental responsiveness from pre- to post-intervention accounted for 25% of the variance in changes in the child’s social interactive behavior.
These two investigations are limited methodologically by a lack of comparison groups or other experimental controls. Nevertheless, the demonstrated progress of the young children enrolled in each of these programs is encouraging. The programs are also instructive examples for the purposes of this article, because each program was designed for contexts that are natural for toddlers with a focus on child-directed early intervention.
The intervention programs described above incorporate a variety of strategies that have been identified in the literature as beneficial to the development of language and communication in young children with ASD or other developmental disabilities. Among the many strategies highlighted throughout the literature are: talking about the child’s current focus of attention (Siller & Sigman, 2002; Watson, 1998; Yoder et al., 1993), engaging in motivating activities that are meaningful to the child and that are within the child’s zone of proximal development (Prizant, Wetherby, & Rydell, 2000), increasing the child’s opportunities to communicate with others through requesting and commenting, and providing contingent responses to the child’s previous verbal or nonverbal communicative acts (Warren et al., 1993; Yoder & Warren, 1998). The remainder of this section will focus on these strategies for facilitating prelinguistic communication and the potential relationship to later language development.
Following the child’s attentional focus has been highlighted in several intervention methods as critical to enhancing prelinguistic communication of children with autism, including the incidental teaching approach used by McGee et al. (1999) and described above, the relationship-based intervention of Mahoney and Morales (2003) described above, and the prelinguistic milieu teaching approach of Yoder and Warren (1998), which uses a variety of strategies to elicit nonverbal communication from and give contingent responses to toddlers in a natural preschool group setting. As noted above, Siller and Sigman (2002) found that parents’ ability to follow in on their child’s focus of attention and add contingent, undemanding language input was predictive of gains in language skills as the 1, 10, and 16 year follow-ups for children with ASD.
Although not specific to toddlers with ASD, research on intervening to help parents become more responsive to their children’s communication suggests that promoting such responsive interaction strategies in parents promotes the growth of social-communicative development in children (Girolametto, Verbey & Tannock, 1994; Kaiser et al., 1996; Tannock, Girolametto, & Siegel, 1992). Recent research by Yoder and Warren (2002), however, indicates that the effects of teaching caregivers to be more responsive is mediated by the initial child characteristics, and that this type of intervention model may be most successful in facilitating language development in toddlers who demonstrate low levels of initiating and requesting at the onset of the study. Interestingly, this profile of low levels of initiating and requesting is characteristic of most toddlers with ASD. In addition to talking about what the child is focusing on, some specific strategies for responsive interactions with preverbal children with disabilities, based on the work of Yoder and Warren are (1) linguistic mapping, or putting into words the child’s nonverbally expressed communicative intentions, (2) complying with the child’s communication intent, and (3) imitating the child’s prespeech vocalizations.
Following the attentional focus of a child with autism may be beneficial due to evidence that suggests that children with autism have difficulty following the directional gaze of others and therefore have the potential for increased linguistic mapping errors (Baron-Cohen & Baldwin, 1997). By following the child with autism’s lead, the child is more likely to correctly map linguistic input with the correct referent. In addition, following the lead of a child with autism increases the likelihood that the child is interested and motivated in a particular activity and thus more likely to benefit from accompanying linguistic input. Lack of motivation and internal rewards have been hypothesized as contributing to the difficulties observed in children with autism (Dawson et al., 2004).
Engaging in motivating, child-selected activities within the child’s current abilities has also been highlighted in the literature as beneficial to language and communication development. Prizant and colleagues (2000) suggest that activities should also fall within the child’s current range of developmental functioning. This notion is consistent with Vygotsky’s theory of a zone of proximal development. According to Vygotsky, children are able to demonstrate skill levels that they are unable to demonstrate independently with the support of an expert partner (Vygotsky, 1978). Vygotsky’s theory proposes that optimal learning occurs when input is provided within this zone of proximal development. Therefore, the caregivers’ ability to accurately estimate their child’s current abilities and provide scaffolding that is slightly above this current skill level is believed to facilitate language and literacy development.
In addition to the many strategies that have been highlighted in the literature as beneficial to enhancing the language and communication development of children with autism, specific areas of development have been pinpointed as possibly serving as critical targets for intervention. Specifically, early nonverbal communication skills such as gesture development and joint attention have been a focus of recent research (Capone & McGregor, 2004; Carpenter, Pennington, & Rogers, 2002; Crais, Douglas, & Cox, 2004; Dawson et al., 2004; Siller & Sigman, 2002). Early links between gesture and joint attention development and later language abilities suggest that intervention aimed at ameliorating early delays in these developmental areas have the potential to impact later language and communication development. Whalen and Schreibman (2003) found that behavioral modification treatment was successful at teaching the children with autism in their study to respond, as well as initiate joint attention bids. Although the authors acknowledged that it was difficult to determine if the children had learned a behavioral response for requesting or if they were truly intentionally using gestures for social sharing, the authors indicated that the children in their study initiated spontaneous joint attention bids in different settings with their parents who were not trained in the behavior modification program. The authors suggested that the behavioral intervention program increased the social awareness of the children with autism thus influencing their desire to share with others.
Additionally, research has been conducted examining the effect of            peer-supported play in increasing joint attention (Zercher et al., 2001). Results indicated that peer supported play was successful at increasing the joint attention skills of two twin boys with autism. In this study, the children with autism were paired with typically developing children who were considered to be “expert” play partners. The play partners were trained to facilitate interactions with the two boys with autism during free play activities. The results indicated that participation in an interactive play group with “expert” play partners increased the boys shared attention to objects. In addition, increases were found in the number of play acts produced by the boys with autism as well as the number of verbal utterances produced by the two boys. One explanation provided by the authors for the increases observed involved the motivation of the boys with autism. The authors suggested that by fully immersing the boys in play where they were expected to be partners in a play situation, the boys were more motivated to participate and therefore more aware of the social interaction.

Collaboration with Families

 As early intervention clinicians strive to provide functional assessments and effective interventions for toddlers with ASD in natural environments, collaboration with the families of such children becomes imperative. As stated previously in this article, the voices of the family members of a child with ASD need to be heard throughout the assessment process in terms of creating both short- and long-term goals for the child. The most effective intervention and program decisions will be those that include the needs and priorities of the family members, as all members of the family will be participating in some way in the development and education of their child with ASD. For many families of children with ASD, family life revolves around autism. Yet in terms of documentation revealing the impact of ASD on families, few empirical research studies have been conducted.
A search of the research literature examining the impact of disabilities on families in general revealed that such publications are limited; even less research has been done specifically on the impact of autism spectrum disorders on families (Norton & Drew, 1994; Schall, 2000). In seminal work, Schopler and Mesibov (1984) edited one of the first exhaustive texts specific to the effects of autism on the family documenting the research literature to date. This text continues to provide professionals who work with children and families impacted by ASD with a foundation of the advocacy and support systems that are required to provide early intervention services. More recently, publications specific to the needs of families and the effects of autism on parents have begun to emerge (Gray, 1998; Randall & Parker, 1999). As professionals continue to include the needs and priorities of the family in assessment and intervention, a deeper understanding of the multidimensional impact of ASD on the family unit is required.
Potential stressors specific to families of children with autism may include: increased number of professional contacts prior to diagnosis, extended length of time before receiving a diagnosis, and later, implementation of intervention services. Other possible areas of familial stress related to ASD include factors related to respite care (Cohen, 1998), depression and/or anxiety about the child’s future, financial constraints and planning, locating needed resources and social support networks (Hecimovic, Powell, & Christensen, 1999), and behavior challenges in public (Marcus, Kunce & Schopler, 1997). Also, while families of typically developing children often have difficult decisions to make regarding childcare, such decisions can be even more challenging for parents of children with ASD. Clinicians working with children and families impacted by ASD must have an awareness of these potential stressors as well as any other needs and concerns of the family unit. Clinicians should be able to assist families in locating support services to more adequately address the varying needs of families in regards to financial assistance, parent education, respite care, and support networks (Hecimovic et al. 1999).
A search on the most recent literature indicates that mothers of children with ASD are most often the primary caregiver for their children with special needs. Therefore, these mothers may be at greater risk for psychological and psychosocial difficulties that can arise from feelings of stress, isolation, and scarcity of resources and supports. In a study by Rodrigue, Morgan and Geffken (1990) mothers of children with ASD were compared to mothers of children with Down Syndrome and mothers of typically developing children. The mothers of the children with ASD reported feeling less parental competence, less marital satisfaction, and less family adaptability than mothers in the comparison groups. Also, higher levels of disrupted planning, caretaker burden, and family burden were documented from the mothers of both the children with ASD and the children with Down syndrome in comparison to the mothers of typically developing children. The mothers of children with ASD reported using coping strategies such as information seeking and self-blame more often than mothers of typically developing children. These mothers also reported a fewer number of people in their social support system, with those individuals who did provide support to the mothers typically providing multiple types of assistance, such as helping with child care and financial hardships, and providing emotional supports.
Mothers and fathers also report differential levels of stress regarding the impact of ASD on the family. Gray (2003) published an article examining gender differences in coping strategies of parents of children with high functioning autism. Mothers in this study reported that they relied heavily on support from other people, including both family members and friends, and that they found this support to be essential. Gray postulated that a diagnosis of ASD may have very different meanings for mothers and fathers. He went on to propose that coping strategies may be determined by each individual’s role in the larger family unit with levels of stress being influenced by the family member’s occupation and specific interactions with the child. The mothers in this study were most likely to be the primary caregivers and therefore experience the brunt of stressors in managing the child’s needs, behaviors, and appointments; fathers, however, reported much less contact and direct stress impact of autism as it related to work and family life. While mothers were more likely to report that their child’s autism had severely affected their emotional health, fathers perceived a greater family impact but a lesser personal impact of their child’s autism.
Gray (2002) published a longitudinal study that documented the social experiences and adaptive strategies of both mothers and fathers of children with ASD. He documented how these parents coped in daily life over a ten-year period. Through years of ethnographic interviews with 35 parents Gray noted parental concerns such as: parent emotional distress and depression, coping with behavior problems in social situations, feelings of isolation, and career problems. Specifically, mothers of children with autism reported that their children’s diagnosis prevented them from returning to work at all or restricted the hours and/or type of employment they were able to maintain. While slightly more than half of the families reported that their situation at the end of the study period was better than it had been a decade before, future planning for their children remained a significant stressor throughout the years of the study.
As the young child with ASD grows and matures, and his or her family’s needs and priorities change, so too will there be changes in the roles of professionals who support the family (Gabriels & Hill, 2002). Therefore, collaboration practices between family members and clinicians that facilitate respect and recognition of the unique child and family circumstances will serve all of those involved in early supports and services for toddlers with ASD. Research examining the coping strategies of families of children with ASD as well as the potential impact of raising a child with this type of disorder on the family unit is critical. Additionally, the need for collaboration skills between families and professionals as well as strategies for ameliorating the devastating effects of autism continues to be an imperative goal of future research.
Summary
The diagnosis ASD in children under the age of three years is increasingly possible, and therefore clinicians are more likely to have the opportunity to provide early intervention services to these children and their families. Research on factors affecting outcomes in children with ASD suggests that assessing and promoting play, imitation, and preverbal intentional communication in toddlers with ASD via direct intervention with the children and collaborations with caregivers to promote caregiver responsivity to children and address family needs for support and information may result in improved language, communication, and adaptation for the children beyond what can be achieved when diagnosis and intervention occur at later developmental points. Despite limited research testing communication intervention strategies with toddlers with ASD and a need for expansion of research in this area, clinicians can nevertheless apply concepts supported by the existing literature in developing interventions for toddlers with ASD and their caregivers.

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