Articulation generalization of voiced-voiceless sounds in hearing-impaired children

Eight hearing-impaired children participated in a study exploring the effect of training (+) or (-) voicing on generalization to cognates. In an experimental multiple baseline study across behaviors, children were trained on pairs of voiced and voiceless target sounds that they had previously omitted in final position. The pairs consisted of the /t/ and /g/ and the /d/ and /k/. When /t/ was trained, generalization was tested to (a) untrained words with the /t/ in the final position and (b) untrained words containing /d/ (the cognate) of the /t/. In like manner, when /d/ was trained, generalization was tested to both the /d/ and /t/ words. The /g/ and /k/ received identical treatment. A contrast procedure was used to teach the children to produce the final consonants. When training criterion was reached, generalization was tested. Results showed that 6 of the 8 children generalized both the voiced and unvoiced target sounds to 50% or more of the target sound probe items. Results also indicated that more generalization occurred to the voiceless cognate from voiced target sound training than occurred to voiced cognates from voiceless target sound training.