This dissertation examines the associations between pragmatic meaning categories in English and specific realizations of prosodic prominence. It has been well-established that in Mainstream American English (MAE), prominence is often used to convey contrast. A more limited set of studies suggests that prosodic prominence may also be capable of…

Purpose: The /[voiced alveolar approximant]/ productions of young children acquiring American English are highly variable and often inaccurate, with [w] as the most common substitution error. One acoustic indicator of the goodness of children's /[voiced alveolar approximant]/ productions is the difference between the frequency of the second…

Purpose: Reduced use of visible articulatory information on a speaker's face has been implicated as a possible contributor to language deficits in autism spectrum disorders (ASD). We employ an audiovisual (AV) phonemic restoration paradigm to measure behavioral performance (button press) and event-related potentials (ERPs) of visual speech…

Purpose: Auditory feedback is thought to contribute to the online control of speech production. Yet, the standard method of estimating auditory feedback control (i.e., reflexive responses to auditory-motor perturbations), although sound, requires specialized instrumentation, meticulous calibration, unnatural tasks, and specific acoustic…

Speech perception research has commonly relied on untrained listeners to provide impressionistic judgments of second language (L2) speech, and training listeners has been rare. The current study therefore explores the implications of training novice listeners (NLs) to rate accented speech. A total of 60 listeners were recruited, 30 who remained…

Purpose: Recent work suggests that speech perception is influenced by the somatosensory system and that oral sensorimotor disruption has specific effects on the perception of speech both in infants who have not yet begun to talk and in older children and adults with ample speech production experience; however, we do not know how such disruptions…

Purpose: The human voice changes with the progression of neurological disease and the onset of diseases that affect articulators, often decreasing the effectiveness of communication. These changes can be objectively measured using signal processing techniques that extract acoustic features. When measuring acoustic features, there are often several…

Across languages, certain syllables are systematically preferred to others (e.g., "plaf > ptaf"). Here, we examine whether these preferences arise from motor simulation. In the simulation account, ill-formed syllables (e.g., "ptaf") are disliked because their motor plans are harder to simulate. Four experiments compared…

Infants born after fetal growth restriction (FGR)--an obstetric condition defined as the failure to achieve the genetic growth potential--are prone to neurodevelopmental delays, with language being one of the major affected areas. Yet, while verbal comprehension and expressive language impairments have been observed in FGR infants, children and…

Purpose: Armed with the theory of embodied cognition proposing tight interactions between perception, motor, and cognition, this study aimed to test the hypothesis that speech rate-altered Mandarin lexical tone perception in quiet and noisy environments could be affected by the bodily dynamic cross-modal information. Method: Fifty-three adult…

Purpose: Three experiments were conducted to better understand the role of between-word coarticulation in masked speech recognition. Specifically, we explored whether naturally coarticulated sentences supported better masked speech recognition as compared to sentences derived from individually spoken concatenated words. We hypothesized that…

Purpose: Beyond hallmark production deficits characterizing childhood apraxia of speech (CAS), largely attributed to disruption(s) in speech motor planning, children with CAS often present with co-occurring speech perception and language difficulties. Thus, careful consideration of the potential for speech perception difficulties to have cascading…

The Perceptual Assimilation Model (PAM) (Best, 1995) claims listeners directly perceive articulatory gestures of the vocal tract rather than acoustic/auditory signals. Accordingly, the articulatory similarities and discrepancies between native and non-native sounds determine the perceptual assimilation patterns of non-native sounds. This study…

Purpose: Gradual and sudden perturbations of vocal fundamental frequency (f[subscript o]), also known as adaptive and reflexive f[subscript o] perturbations, are techniques to study the influence of auditory feedback on voice f[subscript o] control mechanisms. Previous vocal f[subscript o] perturbations have incorporated varied setup-specific…

The influence of visual impairment (i.e., blindness or low vision) on the development of children's speech sound production has undergone some speculation for over half a century. Children learn to produce speech sounds by utilizing and integrating several cognitive-linguistic and sensory-perceptual processes, which may include processing visual…