The boundary effect, namely the infants' failures to compare small and large numerosities, is well documented in studies using visual stimuli. The prevailing explanation is that the numerical system used to process sets up to 3 is incompatible with the system employed for numbers >3. This study investigates the boundary effect in 10-month-old…

Theoretical phonology has at its heart the assumption of two separate levels of speech sound representations: one less abstract, phonetic, 'surface' level, and one more abstract, phonological, 'underlying' level. Descriptions of phonological neutralisation processes such as German final devoicing hinge on the mappings between these two levels, as…

Shadowing is the act of vocalizing the speech one is listening to as simultaneously as possible. The primary function of shadowing is learners' listening skill and pronunciation skill development. Despite the importance of second language (L2) listening skills, this pedagogical technique has not received focal attention in the field. In this…

The very idea of 'critical language studies' encourages one to develop a sense of criticality; that is, to interrogate the concepts that one uses, to explore the boundaries of one's professional practice, and to push one's thinking, if necessary, into new directions. This is typically done with the aim of contributing to epistemic as well as…

Individual speakers' speech patterns differ from one another, despite presumably similar language input. What are the sources of this individual variability? In this dissertation, I explore sources of individual differences in pronunciation of coronal obstruents (/s/, /t[superscript h]/, /c[superscript h]/, /c/) at the ends of nouns in Korean.…

Background and aims: Fascinations for or aversions to particular sounds are a familiar feature of autism, as is an ability to reproduce another person's utterances, precisely copying the other person's prosody as well as their words. Such observations seem to indicate not only that autistic people can pay close attention to what they hear, but…

This case report describes a young child with inconsistent phonological disorder (IPD). The child presented with unintelligible speech. She made limited progress on individual speech production goals targeting phonological patterns over 4 years, remaining unintelligible. The child was diagnosed with IPD following an inconsistency assessment and…

Purpose: Phonologically complex targets (e.g., [pl-]) are understood to facilitate widespread gains following speech sound intervention, and yet, available research largely features word-"initial" clusters. The present study investigates intervention effects following treatment of complex clusters presented in word-"final"…

Differentiation of speech is predictable from abilities to discriminate the speed at which a sound reaches its optimum amplitude (rise time). This study investigated whether rise time identification of an affricate-fricative continuum would be impacted upon by dyslexia. Children between 10 and 14 years old identified sounds along a continuum of…

Child-directed speech has long been known to influence children's vocabulary learning. However, while we know that caregiver utterances differ from those directed at adults in various ways, little is known about any differences in the lexical properties of child-directed and adult-directed utterances. We compare over half a million word tokens…

Background: Children with phonological impairment present with pattern-based errors in their speech production. While some children have difficulties with speech perception and/or the establishment of robust underlying phonological representations, the nature of phonological impairment in children is still not well understood. Given that…

Purpose: This study investigated vowel and sibilant productions in noise to determine whether responses to noise (a) are sensitive to the spectral characteristics of the noise signal and (b) are modulated by the contribution of vowel or sibilant contrasts to word discrimination. Method: Vowel and sibilant productions were elicited during serial…

Oral communication often takes place in noisy environments, which challenge spoken-word recognition. Previous research has suggested that the presence of background noise extends the number of candidate words competing with the target word for recognition and that this extension affects the time course and accuracy of spoken-word recognition. In…

Much research in child speech development suggests that young children coarticulate more than adults. There are multiple, not mutually-exclusive, explanations for this pattern. For example, children may coarticulate more because they are limited by immature motor control. Or they may coarticulate more if they initially represent phonological…

The goal of this dissertation is to better understand the targets of vowels in speech production. Three experiments investigate vowel production in non-native speech, probing how new vowel categories, and thus targets, are formed. Three research questions are addressed: (1) Do vowels have articulatory targets (as predicted by Browman &…