The Handbook of Language and Speech Disorders. Группа авторов. Читать онлайн. Newlib. NEWLIB.NET

Автор: Группа авторов
Издательство: John Wiley & Sons Limited
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Жанр произведения: Языкознание
Год издания: 0
isbn: 9781119606994
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       3.3.2 General Communication Issues with Cochlear Implants

Task Level
Determine communicative intent High order—cognitive
Suprasegmental interpretation Prosody perception—analysis of acoustic surface
Word recognition Lexical parsing
Segmental recognition Low order—perceptual

      The reason for defining this framework in the current chapter is that it simplifies the discussion of what communication problems are for CI users. Furthermore, it provides a unified explanation for those problems, which in turn might direct attention to various rehabilitation approaches. With speech perception problems taken as the basic underlying problem, we start out by reviewing research on those.

       3.3.3 Recognition of Segments

      On an acoustic surface level, the speech signal can be divided into three dimensions: spectral (determined by frequency content), temporal, and amplitude (intensity). As discussed previously, pitch perception and perceptual judgments in the frequency domain are particularly difficult for CI listeners, which is in large part due to the electrical–neuronal bottleneck. The bottleneck helps in understanding CI users’ speech perception deficits and receptive communication abilities. As a general observation, many implanted children and adults are able to reach a functional level of speech understanding as well as intelligibility, although speech perceptual studies of CI listeners are notorious for showing a large degree of variation in the results. However, besides the fact that this success testifies to the robustness of speech and language perception and production, it belies their deficits in the perception of subtle levels of speech phenomena that are immediately perceptible to normally hearing listeners.

      A recent review of consonant and vowel perception in children and adults with CIs as measured with nonsense word tests, performed by 581 postlingually deafened and 66 prelingually deafened participants in the course of 50 studies, noted that CI users have more difficulty with the identification of vowels and consonants than NH controls, who tend to perform at or near ceiling level (Rødvik, von Koss Torkildsen, Wie, Storaker, & Silvola, 2018). The postlingually deafened participants had a mean score of 76.8% on vowel identification and 58.4% on consonant identification, whereas this was 67.7 and 47.7%, respectively, for the prelingually deafened subjects. The differences between the two groups was, however, not significant. Vowels and consonants that are most often confused are those that have the same articulation manner and/or duration and voicing but different places of articulation, such as the consonants /p, t, k/ or /m, n/ and the vowels /&ip.iscp;, ɛ, ʌ, ʊ/.

       3.3.4 Word Recognition

      In contrast to the identification of individual segments, the identification