Autistic Spectrum Conditions (ASC) comprise a complex and diffuse set of behaviors which are essential for diagnosis, according to the Diagnostic and Statistical manual (DSM IV). Before the age of three years, the child will show delayed, or abnormal, functioning in social interaction, in language used in social communication, and in imaginative or symbolic play. The current article focuses mainly on the second of these deficits, that is an impairment in communication, although, of necessity, such an impairment will also involve the first of these problems (i.e. abnormal social interaction), as it is difficult to conceive of a problem in one of these areas that does not impact on the other. Moreover, the two processes, language and social interaction are intimately related to one another. In terms of impaired communication in those with ASC, this is indicated by one or more of the following behaviors (see DSM IV): (a) delayed or absent development of spoken language for which the patient doesn't try to compensate with gestures; (b) in person's who can speak, inadequate attempts to begin or sustain a conversation; (c) language that is repetitive, stereotyped or idiosyncratic; and (d) appropriate to developmental stage, absence of social imitative play or spontaneous, make believe play.
A few children with ASC do not acquire speech at all. By the age of one year, most children can use simple one-syllable words, but about 50% of children with ASC cannot (Seligman et al., 2001). Those children with ASC who do acquire spoken language, often use language in unusual ways, for example, they may not combine words into meaningful sentences (Yapko, 2003), they may make high pitched sounds, or display echolalia, which is repeating a certain sentence, or word, over a period of time, is common in children with ASC (Yule & Rutter, 1987).
For children with ASC who do acquire verbal skills, notably those who may display Asperger's syndrome, language can be 'overly' grammatical, and lacking in colloquialisms. For example, children with ASC tend to reverse the pronouns "I" and "You", and tend to refer to themselves by their name (Lee, Hobson, & Chiat, 1994). While most normal children often misuse the 'ing' rule at an early stage in their language development, children with ASC continue to make this error, even when they are much older (Wing, 1976). Some children with ASC who are only mildly affected may exhibit slight delays in language, but still have great difficulty sustaining a conversation. The 'give and take' of normal conversations is hard for them, although they often carry out a monologue on a favorite subject, giving no one else the opportunity to comment, to a greater extent than do typically developing children (National Institute of Mental Health, 2004).
There have been many notable advances in the development in language using Applied Behavior Analytic (ABA) techniques. These have been documented in many places previously (see Greer & Ross, 2007), and now form the basis of many ABA approaches to the treatment of ASC (e.g., Greer & Ross 2007). Such approaches have shown tremendous improvements in the ability of children with ASC to use words, to tact and mand, and to understand those words that are employed by adults and their peers. In recent review of the literature Makrygianni and Reed (2008) found an average effect size of approaching 1.0 in studies that have examined the impact of ABA programs on the receptive and expressive verbal ability of children with ASC. This suggests an average improvement of around 15 points on a standardized measure of linguistic ability, often over a period of around one to two years. Given the previous pessimistic prognosis for language use in such children, this improvement is highly impressive, and cause for optimism.
However, while these studies may often show an improvement in the use of functional language, they do not necessarily show an improvement in the ability of the children with ASC to use language in a 'typical' manner - that is to say grammatically. …