Purpose: Phonological processing skills, or using phoneme knowledge to process language, in preschool- and kindergarten-age children are an important indicator of children's future reading abilities. However, assessing phonological processing skills can be difficult in children with speech sound disorders because scoring often requires that…

Background and Aim: Recently, there has been a lot of interest surrounding the term gestalt language processor (GLP) which is associated with Natural Language Acquisition (NLA): a protocol intended to support the language development of autistic people. In NLA, delayed echolalia is presumed raw source material that GLPs use to acquire language in…

There is a long-standing debate in the literature about the benefits that acoustic components of Infant Directed Speech (IDS) might have for infants' language acquisition. One of the highly contested features is vowel space expansion, which refers to the enlargement of the acoustic space between the corner vowels /i, u, a/ in IDS compared to Adult…

Background: Parkinson's disease (PD) has an impact on speech production, manifesting in various ways including alterations in voice quality, challenges in articulating sounds and a decrease in speech rate. Numerous investigations have been conducted to ascertain the oral-diadochokinesis (O-DDK) rate in individuals with PD. However, the existing…

In this dissertation, I investigate how people navigate ambiguity in everyday speech, with a focus on quantifier-negation sentences. Combining corpus analysis, behavioral experiments, and computational modeling in the Rational Speech Act framework, I explore preferred interpretations of quantifier-negation and examine the contexts and prosodies…

Background: The detection and description of language impairments in neurodegenerative diseases like Alzheimer's Disease (AD) play an important role in research, clinical diagnosis and intervention. Various methodological protocols have been implemented for the assessment of morphosyntactic abilities in AD; narrative discourse elicitation tasks…

This dissertation investigates how the abstract representation of vowels affects spoken word recognition in Brazilian Portuguese and American English by examining two issues in theoretical phonology and speech processing: underspecification theory, and underlying representation when there is alternation. Three experiments were conducted in…

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…

Noise is a common impedance to easy and accurate speech understanding. In the presence of noise, speech processing mechanisms proceed with partial or ambiguous inputs, and listeners will engage additional cognitive resources to make sense of what they hear. The extent to which this is situation is affected by diminished exposure to a language is…

The prevalent "core phonological deficit" model of dyslexia proposes that the reading and spelling difficulties characterizing affected children stem from prior developmental difficulties in processing speech sound structure, for example, perceiving and identifying syllable stress patterns, syllables, rhymes and phonemes. Yet spoken word…

People with aphasia may produce speech errors or pauses during speaking turns. A communication partner may choose to guess the person's intended meaning, or may allow the person time to repair their turns (i.e., edited turns). The aim of this study was to understand the topic-related effects that occur when speakers without aphasia allow their…

Background: Cleft lip and palate is one of the most common oral and maxillofacial deformities associated with a variety of functional disorders. Cleft palate speech disorder (CPSD) occurs the most frequently and manifests a series of characteristic speech features, which are called cleft speech characteristics. Some scholars believe that children…

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…

To learn the meaning of a new word, or to recognize the meaning of a known one, both children and adults benefit from surrounding words, or the sentential context. Most of the evidence from children is based on their accuracy and efficiency when listening to speech in their familiar native accent: they successfully use the words they know to…

Background: It is assumed that language impairments post-stroke do not show much improvement after the phase of spontaneous recovery, especially in the chronic stage. Several studies have reported language recovery and factors influencing it in the acute stages of stroke. There is limited literature focusing on language recovery in the chronic…