The role of referential speech in sign learning by mentally retarded children: a comparison of total communication and sign-alone training.

We conducted two experiments to assess the role of referential speech during sign training in which the spoken words corresponding to signs were receptively known to the participants. An alternating treatments design was used to compare sign acquisition across two teaching conditions in which referents were presented either with or without the corresponding verbal label. During the first experiment, signs were taught concurrently; during the second experiment, signs within each of the respective conditions were taught in a serial fashion. In both experiments, signs taught by total communication were acquired faster than those taught by sign-alone training.