Not available / text

published_or_final_version / abstract / toc / Linguistics / Master / Master of Arts

published_or_final_version / English Studies and Comparative Literature / Master / Master of Philosophy

This dissertation investigates the processing of speech variability, allophonic and indexical variation in Japanese. A series of speech perception experiments were conducted with reduced and fully voiced vowels in Japanese as a test case. Reduced vowels should be difficult for listeners to hear because they are acoustically less salient than fully voiced vowels, due to the lack of relevant physiological properties. On the other hand, reduced vowels between voiceless consonants represent more common phonological patterns than fully voiced vowels. Furthermore, previous studies found that Japanese listeners were capable of hearing completely deleted vowels. Listeners intuitively maintain CV syllables in perception, hearing a vowel after each consonant in order to avoid obstruent clusters (a violation of Japanese phonotactics).It was found that listeners made good use of acoustic, phonological, and phonotactic knowledge of their native language for processing allophonic variants. In word recognition, listeners performed better when reduced vowels were in the environment where vowel reduction was expected. The phonological appropriateness of an allophone was judged in relation to adjacent consonants on both sides, and the facilitatory effect of appropriateness of reduced vowels surpassed the inhibitory effect of their acoustic weakness. However, in terms of sound detection, listeners found reduced and fully voiced vowels equally easy to hear in an environment where vowel reduction was expected. Although reduced vowels were phonologically appropriate between voiceless consonants, the phonological appropriateness merely balanced out acoustic weakness; it was not strong enough to surpass it. In addition, the phonological appropriateness of an allophone was judged based only on the preceding consonant, which suggests that listeners processed sounds linearly. Furthermore, the study found that phonological appropriateness of the allophone was affected by dialectal differences and speech rates. Listeners' preference for a certain allophone was influenced by the phonology of a listeners' native dialect and expectation was skewed by fast speech rates.This study suggests that current speech perception models need modification to account for the processing of speech variability taking language-specific phonological knowledge into consideration. The study demonstrated that it is important to investigate at which stage phonological inference takes place during processing.

Six experiments were conducted to address the role of phonological information in visual word recognition. A semantic decision task was used to ensure that word meanings were accessed. Experiments 1-4 showed that subjects make more false positive errors on homophone foils (e.g. living thing-FLEE) than on spelling controls (e.g. living thing-FLEX) only when both members of the homophone pair are uncommon and are similarly spelled. In Experiment 5, there was an increase in errors on low but not high frequency homophone category exemplars when they were preceded by a word related to the other member of the homophone pair (e.g. SHATTER-BRAKE). In Experiment 6, subjects produced longer decision latencies on homophone exemplars than on semantic controls only when they were low in frequency. These results indicate that, even in skilled readers, phonological information mediates the access of meaning for low frequency words, and that orthographic activation also contributes to the activation of their meanings.

This thesis investigates change in a number of phonological variables in New Zealand English (NZE) during a formative period of its development. The variables under analysis are the short front vowels /ɪ/, /ɛ/, /æ/, the front centring diphthongs /ɪə/ and /ɛə/, and the so-called 'broad A' vowel. The sample includes 30 NZE speakers born between the 1890s and the 1930s (the 'Intermediate period'). Acoustic analysis reveals that the short front vowel system develops into one with two front vowels and one central vowel over the intermediate period via a push chain shift. There is evidence for complex allophonisation in the speech of early intermediate speakers. I argue that duration plays an important role in resolving overlap between vowel distributions during this time. With regard to the front centring diphthongs there is approximation of the nuclei of the two vowels in F1/F2 space over the intermediate period as well as incipient merger in the speech of late intermediate speakers. Although the merger is mainly one of gradual approximation, it is argued that patterns of expansion of the vowel space available to both vowels are also found. The analysis carried out on the 'broad A' vowel reveals that whereas flat A was still present in the speech of the earlier speakers from the sample, broad A had become categorical toward the end of the intermediate period. It is shown that, by and large, the process involves discrete transfer of words across etymological categories. The final chapters discuss a number of theoretical implications. Processes such as the NZE front vowel shift suggest that a number of previously recognised concepts, such as 'tracks' and 'subsystems', may either have to be relaxed or abandoned altogether. It is argued that chain shifts of this type come about by rather simple mechanisms that have a strong resemblance to functional principles found in the evolution of organisms. A case for 'fitness' of variants of a given vowel will be made. Phonological optimisation, on the other hand, is not a driving force in this type of sound change.

No description available.

The purpose of this research was to test the hypothesis that speakers with small vowel diagrams. The vowels [I ae a u] were analysed for 20 male subjects by means of a sound spectrograph. From the measurements of vowel formants two speakers with large aoustic vowel diagrams Ball State UniversityMuncie, IN 47306

No description available.

This paper describes an experiment where open and directed prompts were alternated when collecting speech data for the deployment of a call-routing application. The experiment tested whether open and directed prompts resulted in any differences with respect to the filled pauses exhibited by the callers, which is interesting in the light of the “many-options” hypothesis of filled pause production. The experiment also investigated the effects of the prompts on utterance form and meaning of the callers.