Response bias in the perception of deaf speech by experienced and naive listeners

'Non-vocalization': a phonological error process in the speech of severely and profoundly hearing impaired adults, from the point of view of the theory of phonology as human behaviour

'Non-vocalization' (N-V) is a newly described phonological error process in hearing impaired speakers. In N-V the hearing impaired person actually articulates the phoneme but without producing a voice. The result is an error process looking as if it is produced but sounding as if it is omitted. N-V was discovered by video recording the speech of two groups, profoundly and severely hearing impaired adults in four elicitation tasks of varying difficulty, and analysing 2065 phonological error processes (substitutions, omissions, and N-V) according to 24 criteria resulting in 49,560 data points. Results, which are discussed in view of the theory 'Phonology as Human Behaviour' (PHB), indicate that: (a) The more communicative the error process was; the more effort was made for its production and the more frequent its distribution; (b) The easier the elicitation task was, the more frequent the use of communicative error processes; c) The more difficult the elicitation task was, the more frequent the use of the relatively less communicative and easier to produce error processes; and d) The process of N-V functioned like a communicative error process for the group of profoundly hearing impaired adults.

Modifications in deaf children's vowel production: perceptual evidence

This study examined the perceived changes in vowel articulation by profoundly deaf children as a function of the method of teaching: with visual feedback provided by the Computer Vowel Trainer (CVT) vs conventional methods. The assessment carried out by experienced listeners consisted in marking the sounds heard on the vowel quadrilateral. It was found that changes in perception were feedback and age dependent: younger children taught with the CVT were perceived as displaying more mobility in articulation and they approximated more closely the target vowels than their control counterparts or older children. Progress was evident in particular for back and central vowels. Analysis of perceived discrepancies between target and judged vowels, too, suggested that visual feedback was beneficial: perception of experimental children's utterances showed a marked reduction in substitutions with central vowels, a characteristic pattern of deaf speech. Comparison of these findings with the results yielded by the judgement of the same items by naive listeners indicated broad agreement between the two categories of assessors. Results were discussed in terms of the perceptual and articulatory intervening variables with reference to the specific advantages and constraints imposed by evaluating vowel quality on the vowel plane.