Early vocal development in tactually aided children with severe-profound hearing loss

The vocalizations of six children with severe-profound hearing loss were audio-recorded in two conditions during individual speech-language intervention sessions: (a) auditory amplification alone, and (b) auditory amplification plus the Tactaid II, a two-channel vibrotactile device (Franklin, 1986). Utterances were categorized according to the infraphonological framework described by Oller (1980, 1986) and Oller and Lynch (1992). Vocalizations were categorized in a developmental framework relative to mature speech. Those utterances containing well-formed consonant-vowel syllables were transcribed with broad phonetic transcription and analyzed at both the syllabic and segmental levels. Statistically significant differences were found between the two conditions for vocal volubility (i.e., quantity of vocalizations produced); subjects vocalized more when using both auditory amplification and the Tactaid II together than with auditory amplification alone. Trends in the early vocal development of these children with severe-profound hearing loss are described at the infraphonologic, segmental, and syllabic levels.