Assessing the functions of vocalizations in children with limited vocal-Verbal repertoires

The current study examined the effectiveness of a newly developed methodology for assessing the functions of emergent vocal-verbal behavior in children with developmental disabilities (Lerman et al., 2005). The purpose of the assessment was to determine the function(s) of specific verbal topographies according to Skinner\u27s (1957) analysis of verbal behavior. Results indicated that for most participants, targeted vocal utterances functioned as either mands, tacts, or both. The reliability of this assessment was first verified through replication (Experiment 1). Participants consisted of two children with developmental disabilities, between the ages of 2 and 10, with very limited vocal-verbal repertoires, exhibiting at least two clearly emitted vocalizations. However, attempts at replication were only moderately successful as additional manipulations became necessary to occasion responding with two of three participants. Experiment 2 aimed to address some of the limitations of Experiment 1. Results obtained in Experiment 2 suggested that participants’ targeted vocalizations served as tacts, echoics, or both. Results are discussed in terms of the utility of this methodology for the selection and development of effective language interventions as well as implications for our current knowledge of verbal behavior and teaching technology