Previous research has indicated that speech and linguistic variables develop concurrently. When one aspect of speech and linguistic development is delayed, there are typically associated delays in another area as well. This interactive relationship has been studied extensively in the context of phonological and syntactical development, as well as fluency and syntactical development. The relationship between intelligibility and linguistic proficiency has not been studied as extensively. The purpose of this study was to examine the relationship between varying levels of intelligibility and length and complexity of language in preschool-aged children. Mean length of utterance was correlated with the mean percentage of intelligible words in a continuous speech sample. The following questions were addressed: 1. Does a significant positive correlation exist between MLU and percentage of intelligible words in a continuous speech sample? 2. Are there significant differences in the correlations of MLU and percentage of intelligible words between four groups of young children with a range of intelligibility levels: mild, mild-moderate, moderate-severe, and severe? A continuous speech sample was collected from each of the subjects. Children were separated into four groups based on intelligibility ratings of mild, mild-moderate, moderate-severe, and severe. These ratings were based on the percentage of mean intelligible words in a continuous speech sample. Correlations between mean length of utterance (MLU) and the percentage of intelligible words (PIW) were obtained using the Pearson Product Moment Correlation. Regression analysis was used to determine whether a significant difference exists between the correlations for the four groups of intelligibility. An overall significant positive correlation was found between MLU and PIW when the four groups of subjects were combined. Significant correlations were also found between MLU and PIW for the groups with intelligibility ratings of mild and mild-moderate. No significant correlations were revealed between the two variables for the moderate-severe or severe groups. Regression analysis indicated no significant differences in the correlations for the four groups of intelligibility. This resulted in a failure to reject the null hypothesis that the correlations among the four groups of intelligibility levels will be the same.

Speech-language pathologists are routinely called upon to make professional assessments concerning a speaker's level of intelligibility. The use of subjective judgement procedures for estimating a percentage of intelligibility is the general practice of many speech-language pathologists because they require minimal time. Although efficient, these methods lack any form of numerical support, and their validity and reliability is questionable. The standard within the field that provides data support is the orthographic transcription method, but it is considered to be too time-consuming for practical application (Samar & Metz, 1988). Researchers continue to seek a measure that is both valid and efficient to be used clinically. The purpose of this study was to establish validity of a check-slash transcription method used to provide objective numerical support for assigning percentage of intelligibility for individuals with moderate speech impairments. The study sought to answer the following questions: 1) Is the check-slash method of transcription a valid measure for quantifying percentage of intelligibility? 2) Is the check-slash method a more time-efficient procedure than the orthographic transcription method? The subjects for this study were 20 graduate students from Portland State University, that were randomly assigned to two transcription groups (check-slash or orthographic}. Each listener transcribed 12 samples taken from 2 girls and 10 boys between the ages of 4:1 and 5:6 with a moderate degree of phonological deficiency. The data were analyzed using individual Mann-Whitney U Tests for each of the 12 samples. Results indicated no significant difference between the check-slash and orthographic transcription methods when used to assign a percentage of intelligibility to individuals with a moderate speech deficit. Although no significant difference was found, interrater reliability for both methods was low. This study established efficiency for the check-slash transcription method when compared to the orthographic method. Increased efficiency for the check-slash method ranged from 38% to 54% over the orthographic method. Results may also indicate that listener perception may influence each clinician's ability to be accurate in their assessments.

This investigation was conducted to determine whether the removal of hearing aids from these children for eighteen hours (+ 1/2 hour and including sleep time) would result in reduced speech intelligibility as perceived by a panel of listening judges who were unfamiliar with the speech of the deaf.

'Clear speech' is a speaking style that talkers often employ when they know they may have trouble being understood, as when speaking in noise or to a person with a hearing loss. When 'clear speech' produced by native talkers is presented in noise to native listeners, it has been shown to be about 10-15 percentage points more intelligible, on average, than normally produced speech. Recent research has shown that bilingual listeners may experience a smaller intelligibility benefit than monolingual listeners from 'clear speech' produced by monolingual talkers. The present study compares the ability of monolingual and bilingual talkers to produce this clear speech intelligibility benefit. The present study investigates the hypothesis that bilinguals may produce a smaller intelligibility benefit than monolinguals when asked to speak clearly. Three groups of talkers were recorded: 13 monolingual native English speakers, 22 'early' Spanish-English bilinguals, with an age of onset of learning English (AOL) of 12 or earlier, and 14 later Spanish-English bilinguals, with an AOL of 15 or later. Talkers produced the target words "bead, bid, bayed, bed, bad" and "bod" in both clear and conversational speech styles. Two repetitions of each word were mixed with noise and presented to monolingual English-speaking listeners across two days of testing. Both monolingual and early bilingual talkers showed a similar degree of clear speech benefit in noise (about 5.5%). Later bilinguals were the least intelligible overall and showed a smaller overall clear speech benefit in noise. Surprisingly, early bilinguals were significantly more intelligible than monolinguals in both speaking conditions (by about 6.5%). For the later bilinguals only, performance was significantly worse for one target word ("bid") in the clear speech condition than in the normal speech condition. These data suggest that later bilinguals, but not early bilinguals, may experience a relative disadvantage when speaking in noise, due to a reduced ability to improve intelligibility by speaking more clearly. Therefore, these persons may benefit from communication strategies or accent reduction programs designed to increase their ability to make themselves understood in difficult speaking environments.

<p><p><p>This study aimed to identify some of the strategies students used when pronouncing unfamiliar words. Questionnaires were handed out to 94 students in the 9th grade in a medium-sized Swedish town. In addition, two teachers and 13 students were interviewed. The results indicate that the students had acquired some basic knowledge about the English sound system from phonetic training in their past education. However, there seemed to be a tendency among the students to use the trial-and-error strategy to a larger extent than using tools such as phonetic transcription in order to figure out the pronunciation of a word. The results also show that the teachers did not teach planned lessons on pronunciation, but instead it was more common that they responded to errors made by students. In conclusion, the results show that the students' knowledge in pronunciation in general was limited. In addition, there seemed to be a connection between the way the students and the teachers approached pronunciation and the student's ability to solve pronunciation issues.</p><p> </p><p> </p><p> </p></p></p>

Quantitative relationships were established between speech intelligibility and gaze patterns when subjects listened to sentences spoken by a single talker at different auditory SNRs while viewing one or more talkers. When the auditory SNR was reduced and subjects moved their eyes freely, the main gaze strategy involved looking closer to the mouth. The natural tendency to move closer to the mouth was found to be consistent with a gaze strategy that helps subjects improve their speech intelligibility in environments that include multiple talkers. With a single talker and a fixed point of gaze, subjects' speech intelligibility was found to be optimal for fixations that were distributed within 10 degrees of the center of the mouth. Lower performance was observed at larger eccentricities, and this decrease in performance was investigated by mapping the reduced acuity in the peripheral region to various levels of spatial degradation.

Quantitative relationships were established between speech intelligibility and gaze patterns when subjects listened to sentences spoken by a single talker at different auditory SNRs while viewing one or more talkers. When the auditory SNR was reduced and subjects moved their eyes freely, the main gaze strategy involved looking closer to the mouth. The natural tendency to move closer to the mouth was found to be consistent with a gaze strategy that helps subjects improve their speech intelligibility in environments that include multiple talkers. With a single talker and a fixed point of gaze, subjects' speech intelligibility was found to be optimal for fixations that were distributed within 10 degrees of the center of the mouth. Lower performance was observed at larger eccentricities, and this decrease in performance was investigated by mapping the reduced acuity in the peripheral region to various levels of spatial degradation.

published_or_final_version / Speech and Hearing Sciences / Master / Master of Science in Audiology

In an increasingly global world, there is a growing demand for pronunciation instruction. A focus on intelligibility as the goal in pronunciation instruction has risen to the forefront of the literature. Suprasegmentals are a practical goal for instruction since they have been shown to have a greater impact on overall intelligibility, but many language curricula do not allocate time or resources to pronunciation instruction at all, making it difficult for teachers to incorporate much needed suprasegmental learning in language classrooms. This Report suggests a practical way to incorporate suprasegmental learning in a mixed language background classroom: a project that incorporates a Web 2.0 tool, VoiceThread, and Covert Rehearsal Model strategy use. / text

published_or_final_version / toc / Speech and Hearing Sciences / Master / Master of Science in Audiology