Severe problem behavior among children with pervasive developmental disorders including autism is relatively prevalent (Horner, Carr, Strain, Todd & Reed, 2002) and costly both to the individual and society (Schroeder, Rojahn, & Oldenquist, 1989). Severe forms of behavior problems such as self-injurious behavior (SIB) or aggression can hinder communicative development and limit verbal and nonverbal communication capacity (National Research Council, 2001).
Behavioral interventions based on the function of the problem behavior have been successfully applied to children with pervasive developmental disorders for a range of problem behaviors including SIB (Carr & Durand, 1985) and aggression (Richman, Wacker, & Winborn, 2001). Identifying a functional relation through analyses designed to expose reinforcement contingencies before treatment increases the likelihood of developing a targeted function-matched intervention to decrease problem behavior and increase adaptive behavior. It is important to identify a behavioral function prior to treatment selection for severe behavioral problems because interventions based on behavioral function are more likely to be effective than arbitrarily chosen interventions (Carr & Durand, 1985; Repp, Felce, & Barton, 1988; Wacker et al., 1998; Wacker et al., 2005).
Among behavioral interventions, functional communication train ing (FCT) consists of teaching communicative responses such as words, gestures, or signs that are used to effectively compete with problem behavior by producing the same functional reinforcer (Carr, 1988; Wacker et al., 1996). Carr and Durand (1985) demonstrated the power of such an approach with children (N = 4) diagnosed with autism by developing a functional assessment tool to identify environmental conditions in which problem behaviors such as aggression, self-injury, and tantrums occurred. The results of the functional assessment were used to define and teach an appropriate replacement behavior with corresponding reductions reported in problem behavior. Wacker et al. have demonstrated consistently (e.g., 1998, 2005) that FCT is highly effective in reducing problem behavior displayed by individuals with developmental disabilities including autism.
Less clear, however, is empirical guidance on selecting the type or form of communicative response to be used during FCT when more than one form (e.g., verbal, gestural) concurrently exists in the child's repertoire. Recently, Ringdahl et al. (2008) compared two mand topographies (high and low proficiency) during FCT and concluded that FCT was more effective when the high proficiency mand was incorporated into FCT. There are only a limited number of studies, however, explicitly examining the effects of alternative modes of communication on verbal communication in autism and related pervasive developmental disorders. Bondy and Frost (1998) reported that alternative modes of communication do not prohibit the acquisition of verbal behavior, but may actually promote it. They demonstrated that a boy who began training with picture cards began speaking after using the system for 11 months. Eighteen months later his speech replaced the cards as his mode of communication. More recently, Charlop-Christy, Carpenter, Le, LeBlanc, and Kellet (2002) reported an increase in spontaneous and imitative speech following the implementation of picture cards. Further, Ganz and Simpson (2004) found that picture card use was mastered rapidly and word utterances increased in number of words and complexity.
The use of an alternative mode of communication in the form of a mand or request for a functional reinforcer, can also lead to a decrease in problem behavior. Frea, Arnold, and Vittimberga (2001) reported that the problem behavior of a four-year-old boy with autism decreased when he started using the Picture Exchange Communication System. Winborn et al. (2002) showed for two subjects that both existing and novel requests were effective replacements for problem behavior using a con-current-schedules design, without a reversal or extinction phase. …