Stimulus-stimulus pairing and subsequent mand acquisition of children with various levels of verbal repertoires.

Effects of a stimulus-stimulus pairing procedure on the subsequent acquisition of mand operants were investigated. An attempt was made to shape novel sounds that emerged through the pairing procedure into a mand. Six children, aged two to five years, with moderate to severe language and communication delays, participated. Two conditions were used following the pairing condition: postpairing and direct reinforcement. The emergence of mands was compared across these conditions. An additional analysis was made of the relation between participants' baseline verbal repertoires and the effects of the pairing and the emergence of mands. Results indicate the possibility of stimulus control from a stimulus-stimulus pairing to mand as shown in two of the participants who had demonstrated high rates of vocal play and low to no verbal repertoire prior to this study. Target vocal sounds during postpairing and direct reinforcement condition remained at zero to low levels for participants with high verbal repertoire and little vocal play, warranting future studies on relations between the pre-existing verbal repertoire and the effectiveness of stimulus-stimulus pairing.