Thesis--Lund. / Includes bibliographical references (p. 116-121).

Thesis--Lund. / Bibliography: p. 116-121.

Thesis (Ph. D.)--University of Oregon, 2006. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 129-137). Also available for download via the World Wide Web; free to University of Oregon users.

The current dissertation represents one of the first systematic studies of the distribution of speech errors within supralexical prosodic units. Four experiments were conducted to gain insight into the specific role of these units in speech planning and production. The first experiment focused on errors in adult English. These were found to be systematically distributed within the highest-level supralexical prosodic unit, the Intonational Phrase (IP), providing evidence for its psychological reality. The specific distribution of errors--fewest in unit-initial position, with a gradual increase in errors across the unit--was interpreted to suggest that the IP functions as a planning domain: the unit is activated as a whole, and activation gradually decays with time leading to an increase in errors. The second experiment was motivated by the idea that a decrease in IP activation is best understood in the context of working memory processes. Children's speech was examined in preference to adult speech because it is less automatized and so likely more influenced by working memory. The findings were that children with better working memories produced shorter IPs and relatively more anticipatory errors than children with poorer working memories. The results provided further evidence for the role of IPs in planning. The third and fourth experiments extended the investigation to another language, Korean, and examined the role of a mid-level prosodic unit, the Accentual Phrase (AP), in planning and production. The results indicated the same pattern of error distribution in the Korean IP as in the English IP. In contrast, more errors occurred in AP-initial position than in the second half of the unit, and the elicited errors tended to preserve AP-internal structure. The results were interpreted to suggest that the AP provides a structural frame within which elements are slotted for production. Overall, the results are consistent with the idea that these units play a critical role in the planning and production process. The results also suggest that different units within the prosodic hierarchy function differently: the IP functions as a planning domain, and mid-level units (i.e., AP) provide the structure needed to accomplish serial ordering in speech. This dissertation includes previously published co-authored material.

abstract: Children with cleft palate with or without cleft lip (CP+/-L) often demonstrate disordered speech. Clinicians and researchers have a goal for children with CP+/-L to demonstrate typical speech when entering kindergarten; however, this benchmark is not routinely met. There is a large body of previous research examining speech articulation skills in this clinical population; however, there are continued questions regarding the severity of articulation deficits in children with CP+/-L, especially for the age range of children entering school. This dissertation aimed to provide additional information on speech accuracy and speech error usage in children with CP+/-L between the ages of four and seven years. Additionally, it explored individual and treatment characteristics that may influence articulation skills. Finally, it examined the relationship between speech accuracy during a sentence repetition task versus during a single-word naming task. Children with CP+/-L presented with speech accuracy that differed according to manner of production. Speech accuracy for fricative phonemes was influenced by severity of hypernasality, although age and status of secondary surgery did not influence speech accuracy for fricatives. For place of articulation, children with CP+/-L demonstrated strongest accuracy of production for bilabial and velar phonemes, while alveolar and palatal phonemes were produced with lower accuracy. Children with clefting that involved the lip and alveolus demonstrated reduced speech accuracy for alveolar phonemes compared to children with clefts involving the hard and soft palate only. Participants used a variety of speech error types, with developmental/phonological errors, anterior oral cleft speech characteristics, and compensatory errors occurring most frequently across the sample. Several factors impacted the type of speech errors used, including cleft type, severity of hypernasality, and age. The results from this dissertation project support previous research findings and provide additional information regarding the severity of speech articulation deficits according to manner and place of consonant production and according to different speech error categories. This study adds information on individual and treatment characteristics that influenced speech accuracy and speech error usage. / Dissertation/Thesis / Doctoral Dissertation Speech and Hearing Science 2020

An investigation of concurrent validity of the Non-ah Speech Disturbance Ratio (Non-ah SDR) with the State Form of the State-Trait Anxiety Inventory (STAI). Twenty male college students talked on an anxiety-arousing topic before female audiences who rated observed anxiety. Each subject completed the State and Trait Forms of the STAI. Reliabilities were, by the Intraclass correlation for Raters on Day 1, .63 (p<.01) and Day 2, .20 (p<.05). Pearson's r for scorers was .98 (p<.01). The Non-ah SDR and all other measures of anxiety correlated. A partial correlation test found the naive ratings significantly determined by manifest speech disturbance, as measured by the Non-ah SDR. Certain categories of speech disturbance were only infrequently utilized and added little to the measure as a whole.

Thesis (Ph. D.)--University of California, San Diego, 1982. / Includes bibliographical references (p. 291-299).

Dell (1986) presented a spreading activation model which accounted for a number of early speech error results, including the relative proportions of anticipations, perseverations and exchanges found in speech error corpora, the lexical bias effect, the phonological similarity effect, and the effect of speech rate on error rate. This model has had an immense influence on the past 20 years of research into word production, with the original paper being cited over 1,000 times. Many studies have questioned how activation should flow between words and phonemes in this model. This thesis aimed to clarify what current speech error evidence tells us about how activation flows between phonemes and subphonemic representations, like features. Does activation cascade from phonemes to features, and does it feed back? The work presented here extends previous modelling investigations in two ways. Firstly, whereas previous modelling research has tended to evaluate model behaviour using arbitrarily chosen parameter settings, we illuminate the influence of the parameters on model behaviour and propose methods to draw general conclusions about model behaviour from large numbers of simulations at orthogonally varied parameter settings. Secondly, we extend the scope of the simulations to consider output at a subphonemic level, modelling recent data acquired via acoustic and articulatory measurements, such as voicing onset time (VOT), electropalatography (EPG) and ultrasound, alongside older transcribed speech error data. Throughout the thesis, we consider whether parameter settings which lead the model to capture individual results also permit other results to be accounted for and do not cause otherwise implausible behaviour. Through manipulating parameter settings in Dell's (1986) original model, we find that increasing the number of steps before selection generally does not decrease the error rate, but rather increases it, contrary to results reported by Dell (1986). This calls into question the claim that an increase in steps before selection provides a good model of a slower speech rate. We also demonstrate that the model captures the negative correlation reported by Dell, Burger, and Svec (1997) between error rate and the ratio of anticipations to perseverations, and further predicts that there should be a negative correlation between this ratio and the proportion of errors which are non-contextual. However, our results show that no parameter setting allows the model to generate enough exchanges to match even minimum estimates from a reanalysis of multiple speech error corpus reports, without falling foul of other constraints; in particular, limits on the overall number of errors generated. We suggest that the exchange completion triggering mechanism proposed by Dell (1986) is not strong enough, and that current corpus evidence provides little support for his account of word sequencing. Focusing on single word production therefore, the second part of the thesis investigates behaviour of models with output at a subphonemic level. We find that, provided sufficient contextual errors occur at the featural level, a model in which only the identity of the selected phoneme is conveyed to the featural level can account for: (i) the phonological similarity effect found in transcribed records of speech errors (whereas in models with output at the phoneme level, feedback from features to phonemes is required); (ii) detectable influences of intended phonemes in VOT measurements of unintended phonemes, as well as the effect of error outcome lexicality on these results ( findings presented in support of cascading from phonemes by Goldrick & Blumstein, 2006); and (iii) increased similarity of EPG measurements of articulations to reference measurements of competing articulations when production of the competing onset would result in a word (McMillan, Corley, & Lickley, 2009). Initial results appear to con firm however that, in contrast, phonological similarity effects on the relationship of articulatory and acoustic measurements of productions to reference measurements (McMillan, 2008) can only be accounted for in an architecture with feedback from features to phonemes. To strengthen conclusions about articulatory evidence of lexical bias and phonological similarity effects, future work needs to consider the extremely strong effects of frequency observed in these simulations. The results presented in this thesis contribute to a greater comprehension of the behaviour of Dell's (1986) influential model, and further demonstrate that the model can be extended to account for new instrumental evidence, whilst clarifying the constraints on activation flow between phonemes and features which this new evidence imposes.

Thesis (Ph. D.)--University of California, San Diego, 1982. / Includes bibliographical references (p. 291-299).

Thesis (M. Aud.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (leaves 70-75). Also available via the World Wide Web.