The purpose of this study was to further explore previously observed differences in phonological processing between adults who do and do not stutter through a list recall task. Three types of lists of words were generated according to their associations with a lure word: phonological, semantic, and hybrid. For the experimental task, participants were instructed to listen to recordings of lists of 12 words, 4 of each type, and immediately recall them in any order. We looked at recall accuracy and rate of production of each list's associated lure word. For recall accuracy, phonological lists were lowest, hybrid lists were in the middle, and semantic lists were highest. For production of the critical lure, phonological lists were the lowest, semantic lists were in the middle, and hybrid lists were highest. The pattern was the same for recall accuracy and critical lure production for both talker groups; however, the adults who stutter had lower means for each condition in both cases. The results provide further evidence that there are systematic and significant differences in the phonological working memory efficiency of AWS and AWNS, which may contribute to fluency differences. / text

Grapheme-to-phoneme conversion is a necessary part of reading, whether by an automated system or by children. Automated methods play a key role in text-to-speech and automated speech recognition systems. Children learning to read develop grapheme-to-phoneme (G2P) conversion rules that they use extensively until they build up their orthographic lexicon. Various solutions have been proposed for G2P conversion, each addressing specific problems and evaluated for different languages. In this thesis, I introduce a simple approach to G2P conversion that achieves good results, and compare these results to those of a study of children’s reading accuracy in the primary grades. The comparison highlights areas of weakness in the children’s reading skills, as well as particular phonemes for which the G2P system has difficulty. As part of the process, I also compare and discuss the wide range of discrepancies that exist between various French corpora.

This thesis examines the effects of phonics-emphasis Direct Instruction reading programs on the phonological processes of students with teacher-identified reading problems in nine northern and western Melbourne primary schools. The students (131 males and 75 females, mean age 9.7 years, standard deviation 1.2 years) were assigned to the treatment condition or to wait-list comparison groups. Based on the results of a program placement test of rate and accuracy, students were assigned to one of two entry points into the Corrective Reading program (A, B1). The students in the intervention group received 60-65 lessons (in groups of five to ten students) from teachers at their schools, or, for some students, at a resource centre for surrounding schools. An additional study, with younger (mean age 8.8 years) less advanced readers involved a similar design and teaching approach. The program, Teach Your Child to Read in 100 Easy Lessons, was presented to thirteen student s in two settings. When compared with a similar cohort of wait-list students, the students in each program made statistically significant and educationally important gains in such phonologically-based processes as word attack, phonemic awareness, and spelling; and, statistically significant gains, of at least moderate effect size, in phonological recoding in lexical access and phonological recoding in working memory. A further question involved the prediction (from pretest scores) of those students who would not make progress in word attack solely from the reading programs. In this thesis, only the presence or absence of the reading programs predicted improvement in word attack. The studies in this thesis contribute to the long-standing debate on how best to ensure that children learn to read; to the understanding of the relationship between phonemic awareness and reading; to an understanding of the effects of the current system on at-risk children; and, how additional or alternative approaches more attuned to the findings of reading research may improve the effectiveness of the system.

The present study investigated phonological encoding skills in children who stutter (CWS). Participants were 4 CWS (M=10;9years) and 4 children who do no stutter (CNS) (M=12;1 years) The groups were compared in phoneme monitoring and rhyme monitoring, with a tone monitoring task providing a neutral baseline for comparison. Both the phoneme monitoring and rhyme monitoring tasks were performed during silent picture naming. Results revealed that both groups were faster and more accurate when monitoring the rhyme than when monitoring the phoneme. Results further indicated that the children who stutter were significantly slower in both conditions. These findings suggest that there may be a later transition to incremental processing in both typically developing children and those who stutter and that children who stutter may be even less efficient than children who do not stutter. However, these results may have been compromised by a few key variables. / text

A weakness in phonological-processing skills and alphabetic understanding is theorized to be responsible for the lack of reading development with some children. This study investigated the influence of a programme designed to use a direct instruction approach to teach these skills and knowledge on reading development. Fourteen children and the teacher from one classroom in a small urban primary school participated in this study. The students ranged in age from 7 years 7 months to 9 years 9 months, and ranged in reading ability from achieving below to achieving above their comparable chronological age in reading. At the time of the study, the school roll consisted of 81% Maori, 2% Cook Island, and 17% New Zealand European. Of the 14 students involved in the study, 12 were Maori, one was a Cook Island Maori and one was New Zealand European. The study took place over nine months, and consisted of 20-minute direct instruction sessions on phonological-processing skills and alphabetic knowledge and understanding, supported by other daily practice sessions as suggested by the programme's curriculum. Children were administered a range of tests on phonological-processing skills, word attack and identification, and reading comprehension and attitude at the beginning, middle and end of the study period. Comparisons and analysis of the data revealed that there were differences with all groups; i.e., those achieving in reading at, above, or below their expected level, with all aspects tested. Because of other interventions put into place by the classroom teacher, it is not possible to fully attribute the development of skills and understanding, and acquisition of knowledge, to the implementation of the programme. Nevertheless, these results suggest that children responded favourably to the specific, explicit teaching. Although this study was small, the positive response of the Maori and Cook Island Maori participants is worthy of further or closer investigation.

Naming speed (NS) tasks that measure how quickly and accurately participants can name visual stimuli (e.g., letters) are commonly used to predict reading ability. However, the link between NS and reading is poorly understood. Three methods were used to investigate how NS relates to reading and what cognitive processes are involved: (a) changing stimulus composition to emphasize phonological and/or visual aspects (Compton, 2003); (b) decomposing NS times into pause and articulation components; and (c) analyzing eye movements during a NS task. Participants were in three groups: dyslexics (aged 9, 10), chronological-age (CA) controls (age 9, 10), and reading-level (RL) controls (aged 6, 7). We used a letter NS task and three variants that were either phonologically and/or visually confusing while subjects’ eye movements and articulations were recorded, and examined how these manipulations influenced NS performance and eye movements. For all groups, NS manipulations were associated with specific patterns of behaviour and saccadic performance, reflecting differential contributions of NS to reading. RL controls were less efficient, made more errors, saccades and regressions, and made longer fixation durations, articulation times, and pause times than CA controls. Dyslexics consistently scored in between controls, except for the number of saccades and regressions in which they made more than both control groups. Overall there were clear developmental changes in NS performance, NS components, and eye movements in controls from ages 6 to 10 that appear to occur more slowly for dyslexics. Furthermore, pause time and fixation duration were key features in the NS-reading relationship, and increasing visual similarity of the letter matrix had the greatest effect on performance for all subjects. This latter result was demonstrated by the decrease in efficiency and eye-voice span, increase in naming errors, saccades, and regressions, and longer pause times and fixation durations found for all subjects. We conclude that NS is related to reading via fixation durations and pause times; longer fixation durations reflect the greater amount of time needed to acquire visual/orthographic information from stimuli, and longer pause times in children with dyslexia reflect the greater amount of time needed to prepare to respond to stimuli. / Thesis (Master, Neuroscience Studies) -- Queen's University, 2013-09-26 12:24:53.951

We used fMRI to examine the neural substrates of sublexical phoneme-grapheme conversion during spelling in a group of healthy young adults. Participants performed a writing-to-dictation task involving irregular words (e.g., choir), plausible nonwords (e.g., kroid), and a control task of drawing familiar geometric shapes (e.g., squares). Written production of both irregular words and nonwords engaged a left hemisphere perisylvian network associated with reading/spelling and phonological processing skills. Effects of lexicality, manifested by increased activation during nonword relative to irregular word spelling, were noted in anterior perisylvian regions (posterior inferior frontal gyrus/operculum/precentral gyrus/insula), and in left ventral occipito-temporal cortex. In addition to enhanced neural responses within domain-specific components of the language network, the increased cognitive demands associated with spelling nonwords engaged domain-general frontoparietal cortical networks involved in selective attention and executive control. These results elucidate the neural substrates of sublexical processing during written language production and complement lesion-deficit correlation studies of phonological agraphia.

Repeating a word or nonword requires a speaker to map auditory representations of incoming sounds onto learned speech items, maintain those items in short-term memory, interface that representation with the motor output system, and articulate the target sounds. This dissertation seeks to clarify the nature and neuroanatomical localization of speech sound representations in perception and production through multivariate analysis of neuroimaging data. The major portion of this dissertation describes two experiments using functional magnetic resonance imaging (fMRI) to measure responses to the perception and overt production of syllables and multivariate pattern analysis to localize brain areas containing associated phonological/phonetic information. The first experiment used a delayed repetition task to permit response estimation for auditory syllable presentation (input) and overt production (output) in individual trials. In input responses, clusters sensitive to vowel identity were found in left inferior frontal sulcus (IFs), while clusters responsive to syllable identity were found in left ventral premotor cortex and left mid superior temporal sulcus (STs). Output-linked responses revealed clusters of vowel information bilaterally in mid/posterior STs. The second experiment was designed to dissociate the phonological content of the auditory stimulus and vocal target. Subjects were visually presented with two (non)word syllables simultaneously, then aurally presented with one of the syllables. A visual cue informed subjects either to repeat the heard syllable (repeat trials) or produce the unheard, visually presented syllable (change trials). Results suggest both IFs and STs represent heard syllables; on change trials, representations in frontal areas, but not STs, are updated to reflect the vocal target. Vowel identity covaries with formant frequencies, inviting the question of whether lower-level, auditory representations can support vowel classification in fMRI. The final portion of this work describes a simulation study, in which artificial fMRI datasets were constructed to mimic the overall design of Experiment 1 with voxels assumed to contain either discrete (categorical) or analog (frequency-based) vowel representations. The accuracy of classification models was characterized by type of representation and the density and strength of responsive voxels. It was shown that classification is more sensitive to sparse, discrete representations than dense analog representations.

DOES A CONTINUOUS MEASURE OF HANDEDNESS PREDICT READING RELATED PROCESSES AND READING SKILLS ACROSS THE LIFESPAN? by Michele Harrison Brenneman The purpose of this research was to investigate the relationship between handedness, reading skills, and reading related cognitive processes. The research results with regard to handedness, specific reading skills, and reading related cognitive processes are ambiguous at best. The method in which handedness is measured contributes to these diverse research findings, therefore the present investigation addressed these methodological limitations. A large normative sample of up to 1383 participants that ranged in age from 4 to 80 completed the Woodcock Johnson Psycho-Educational Battery-Revised (Woodcock & Johnson, 1989a; Woodcock & Johnson, 1989b) or the Woodcock Johnson Psycho-Educational Battery-Third Edition (Woodcock, McGrew, & Mather, 2001) in combination with the Dean Woodcock Sensory Motor Battery (Dean & Woodcock, 2003) lateral preference scale, a continuous measure of handedness. Polynomial multiple regression analyses indicated curvilinear relationships between handedness and reading comprehension and basic reading skills, along with handedness and auditory working memory. Individuals towards the extremes of the handedness continuum performed lower on the reading related tasks. Therefore, just knowing a general classification of right, left or mixed handed will not provide significant knowledge regarding lateralization or potential cognitive and academic costs and benefits. One overarching implication of these findings is that laterality is an important predictor variable of reading skills and related reading processes, hence knowledge of an individual’s hand preference on a continuum may well be useful for evaluative purposes.

The present study investigated the brain-behavior relationships between cerebellar vermal volume, phonological processing, and verbal working memory in children with Reading Disability (RD) and Attention-Deficit/Hyperactivity Disorder (ADHD). It was hypothesized that there would be differences in inferior posterior vermal volume between those with and without ADHD. Individuals with and without RD were not expected to differ in posterior inferior vermal volume and an interaction in the RD/ADHD group was expected. Children with RD/ADHD were expected to have similar volumes to children who have ADHD. It also was hypothesized that inferior posterior vermal volumes would be correlated with verbal working and phonological short-term memory; anterior vermal volumes were hypothesized to be correlated with elision, and superior posterior vermal volumes were hypothesized to be correlated with rapid object and rapid letter naming. Results indicated that there were no group differences in posterior inferior vermal volume between children with and without RD as well as with and without ADHD. There were also no relationships between phonological processing and verbal working memory. The findings in this study were unexpected and suggest the need for further study between phonological processing, verbal working memory, and vermal volume in children with ADHD and RD.