Abstract
The research literature has revealed mixed outcomes on stimulus-stimulus pairing (SSP) as a potential procedure to promote vocalizations. In this procedure, the experimenter's specific vocalizations are paired with the delivery of conditioned or unconditioned stimuli and it has been used to increase vocalizations in individuals with language delays. Some studies demonstrate an increase in participants' vocalizations, while other studies demonstrate a partial or zero increase in participant's vocalizations. The current study extends the systematic literature review conducted by Shillingsburg et al. Analysis of Verbal Behavior, 31, 215-235, (2015). We included 12 experimental studies, including published peer-reviewed studies, theses, and dissertations, from 2015 and 2024 that investigated SSP to increase vocalizations in participants with language delays. The studies were analyzed according to participants' characteristics and specific features of the SSP procedures. A multilevel meta-analysis was conducted for a portion of the studies reviewed to calculate the effect sizes across cases and studies. Overall, we found a significant effect of the SSP procedure on increased rates of vocalizations of individuals with language delays. Directions for future research are discussed.