Matching Items (3)
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- All Subjects: Speech therapy
- Creators: Dorman, Michael
Description
A multitude of individuals across the globe suffer from hearing loss and that number continues to grow. Cochlear implants, while having limitations, provide electrical input for users enabling them to "hear" and more fully interact socially with their environment. There has been a clinical shift to the bilateral placement of implants in both ears and to bimodal placement of a hearing aid in the contralateral ear if residual hearing is present. However, there is potentially more to subsequent speech perception for bilateral and bimodal cochlear implant users than the electric and acoustic input being received via these modalities. For normal listeners vision plays a role and Rosenblum (2005) points out it is a key feature of an integrated perceptual process. Logically, cochlear implant users should also benefit from integrated visual input. The question is how exactly does vision provide benefit to bilateral and bimodal users. Eight (8) bilateral and 5 bimodal participants received randomized experimental phrases previously generated by Liss et al. (1998) in auditory and audiovisual conditions. The participants recorded their perception of the input. Data were consequently analyzed for percent words correct, consonant errors, and lexical boundary error types. Overall, vision was found to improve speech perception for bilateral and bimodal cochlear implant participants. Each group experienced a significant increase in percent words correct when visual input was added. With vision bilateral participants reduced consonant place errors and demonstrated increased use of syllabic stress cues used in lexical segmentation. Therefore, results suggest vision might provide perceptual benefits for bilateral cochlear implant users by granting access to place information and by augmenting cues for syllabic stress in the absence of acoustic input. On the other hand vision did not provide the bimodal participants significantly increased access to place and stress cues. Therefore the exact mechanism by which bimodal implant users improved speech perception with the addition of vision is unknown. These results point to the complexities of audiovisual integration during speech perception and the need for continued research regarding the benefit vision provides to bilateral and bimodal cochlear implant users.
ContributorsLudwig, Cimarron (Author) / Liss, Julie (Thesis advisor) / Dorman, Michael (Committee member) / Azuma, Tamiko (Committee member) / Arizona State University (Publisher)
Created2015
Description
The purpose of this study was to identify acoustic markers that correlate with accurate and inaccurate /r/ production in children ages 5-8 using signal processing. In addition, the researcher aimed to identify predictive acoustic markers that relate to changes in /r/ accuracy. A total of 35 children (23 accurate, 12 inaccurate, 8 longitudinal) were recorded. Computerized stimuli were presented on a PC laptop computer and the children were asked to do five tasks to elicit spontaneous and imitated /r/ production in all positions. Files were edited and analyzed using a filter bank approach centered at 40 frequencies based on the Mel-scale. T-tests were used to compare spectral energy of tokens between accurate and inaccurate groups and additional t-tests were used to compare duration of accurate and inaccurate files. Results included significant differences between the accurate and inaccurate productions of /r/, notable differences in the 24-26 mel bin range, and longer duration of inaccurate /r/ than accurate. Signal processing successfully identified acoustic features of accurate and inaccurate production of /r/ and candidate predictive markers that may be associated with acquisition of /r/.
ContributorsBecvar, Brittany Patricia (Author) / Azuma, Tamiko (Thesis advisor) / Weinhold, Juliet (Committee member) / Berisha, Visar (Committee member) / Arizona State University (Publisher)
Created2017
Description
Children with hearing impairment are at risk for poor attainment in reading decoding and reading comprehension, which suggests they may have difficulty with early literacy skills prior to learning to read. The first purpose of this study was to determine if young children with hearing impairment differ from their peers with normal hearing on early literacy skills and also on three known predictors of early literacy skills – non-verbal cognition, executive functioning, and home literacy environment. A second purpose was to determine if strengths and weaknesses in early literacy skills of individual children with hearing impairment are associated with degree of hearing loss, non-verbal cognitive ability, or executive functioning.
I assessed seven children with normal hearing and 10 children with hearing impairment on assessments of expressive vocabulary, expressive morphosyntax, listening comprehension, phonological awareness, alphabet knowledge, non-verbal cognition, and executive functioning. Two children had unilateral hearing loss, two had mild hearing loss and used hearing aids, two had moderate hearing loss and used hearing aids, one child had mild hearing loss and did not use hearing aids, and three children used bilateral cochlear implants. Parents completed a questionnaire about their home literacy environment.
Findings showed large between-group effect sizes for phonological awareness, morphosyntax, and executive functioning, and medium between-group effect sizes for expressive vocabulary, listening comprehension, and non-verbal cognition. Visual analyses provided no clear pattern to suggest that non-verbal cognition or degree of hearing loss were associated with individual patterns of performance for children with hearing impairment; however, three children who seemed at risk for reading difficulties had executive functioning scores that were at the floor.
Most prekindergarten and kindergarten children with hearing impairment in this study appeared to be at risk for future reading decoding and reading comprehension difficulties. Further, based on individual patterns of performance, risk was not restricted to one type of early literacy skill and a strength in one skill did not necessarily indicate a child would have strengths in all early literacy skills. Therefore, it is essential to evaluate all early literacy skills to pinpoint skill deficits and to prioritize intervention goals.
I assessed seven children with normal hearing and 10 children with hearing impairment on assessments of expressive vocabulary, expressive morphosyntax, listening comprehension, phonological awareness, alphabet knowledge, non-verbal cognition, and executive functioning. Two children had unilateral hearing loss, two had mild hearing loss and used hearing aids, two had moderate hearing loss and used hearing aids, one child had mild hearing loss and did not use hearing aids, and three children used bilateral cochlear implants. Parents completed a questionnaire about their home literacy environment.
Findings showed large between-group effect sizes for phonological awareness, morphosyntax, and executive functioning, and medium between-group effect sizes for expressive vocabulary, listening comprehension, and non-verbal cognition. Visual analyses provided no clear pattern to suggest that non-verbal cognition or degree of hearing loss were associated with individual patterns of performance for children with hearing impairment; however, three children who seemed at risk for reading difficulties had executive functioning scores that were at the floor.
Most prekindergarten and kindergarten children with hearing impairment in this study appeared to be at risk for future reading decoding and reading comprehension difficulties. Further, based on individual patterns of performance, risk was not restricted to one type of early literacy skill and a strength in one skill did not necessarily indicate a child would have strengths in all early literacy skills. Therefore, it is essential to evaluate all early literacy skills to pinpoint skill deficits and to prioritize intervention goals.
ContributorsRunnion, Elizabeth (Author) / Gray, Shelley (Thesis advisor) / Dorman, Michael (Committee member) / Thompson, Marilyn (Committee member) / Arizona State University (Publisher)
Created2017