Systematic Review of Verbal Operants in Speech Generating Device Research from Skinner’s Analysis of Verbal Behavior

The team read every SGD study that used Skinner’s verbal operants. They found 54 papers on kids with autism, ID, or delays.

They sorted each study by the verbal operant it taught: mand, tact, intraverbal, echoic, or listener.

Most papers taught multiply-controlled mands: “I want cookie” only when the cookie is in sight and the adult is nearby.

Pure tacts, intraverbals, and spontaneous topographies were rare. The field is stuck on request training.

Dixon et al. (2018) and Gwynette et al. (2020) show kids can learn tacts and intraverbals without SGDs. Their positive results highlight the gap Tincani et al. found: we are under-studying these operants in SGD work.

Vladescu et al. (2021) proved smaller stimulus sets speed tact learning. Tincani’s review urges us to apply that lesson inside SGD apps—use 3-6 pictures per set, not 12.

Wichnick-Gillis et al. (2019) got social initiations to generalize from school to home. Tincani’s data say SGD studies rarely test such generalization; we should copy the script-fading model and probe untrained people and places.

If you run SGD therapy, you probably teach requests. That is fine, but it is not enough. Add tact sets with 3-6 pictures. Program brief intraverbal fill-ins. Probe with new listeners and in new rooms. These small shifts move the child from pure requesting to real conversation.