This dissertation examines how listeners' knowledge of interspeaker variability guides their generalization of perceptual learning in multi-talker listening. A series of perceptual learning experiments are conducted to evaluate whether listeners generalize what they have learned about a previous talker's production of sibilants and stop VOT to…

Purpose: Unexpected and sustained manipulations of auditory feedback during speech production result in "reflexive" and "adaptive" responses, which can shed light on feedback and feedforward auditory-motor control processes, respectively. Persons with Parkinson's disease (PwPD) have shown aberrant reflexive and adaptive…

Purpose: This study aimed to evaluate a novel communication system designed to translate surface electromyographic (sEMG) signals from articulatory muscles into speech using a personalized, digital voice. The system was evaluated for word recognition, prosodic classification, and listener perception of synthesized speech. Method: sEMG signals were…

This study investigates the effects of native language experience and phonetic properties on the discrimination of labial-velar versus labial and velar contrasts, as well as voicing contrasts in labials, velars, and labial-velars. Research indicates that phonological perceptions are influenced by native language experience and the specific…

In speech perception tasks with ambiguous bottom-up information, lexical processes have been shown to influence listener responses, such as in phoneme categorization tasks (Ganong, 1980). Proponents of interactive theories of speech perception and spoken word recognition assert this influence is a top-down feedback mechanism that can affect…

While phonetic training in laboratory settings has been shown to be helpful for second language (L2) sounds learning in prior studies , it is still open to debate whether a perception- or a production-based approach can better help adults learn L2 sounds in classroom settings. This study aimed to fill this knowledge gap. The participants were…

Recent work has shown significant sublexical effects of long-term memory in nonword repetition (NWR) using a dichotomous consonant age of acquisition (CAoA) variable (Moore, 2018; Moore, Fiez, and Tompkins, 2017). Performance consistently decreased when stimuli comprised consonants acquired later versus earlier in speech development. To address…

Purpose: The purpose of this study was to explore the relationship between feedback and feedforward control of articulation and voice by measuring reflexive and adaptive responses to first formant (F[subscript 1]) and fundamental frequency (f[subscript o]) perturbations. In addition, perception of F[subscript 1] and f[subscript o] perturbation was…

Purpose: The purpose of this study was to synthesize the methodological variability in the speech perception literature for school-age children with residual speech sound disorder (RSSD), with the primary intention of using the existing knowledge to inform clinical decisions and optimize treatment outcomes for children. Method: Ten electronic…

Language has a rhythmic structure, but little is known about the mechanisms that underlie how it is planned. Traditional models of language production assume that metrical and segmental planning occur independently and in parallel (Roelofs & Meyer, 1998). We test this claim in three experiments. In Experiment 1, participants completed an…

Purpose: This study evaluated whether outcomes from treatment, which includes ultrasound visual feedback (UVF), would be more or less effective when combined with auditory perception training for children with residual /[voiced alveolar approximant]/ errors. Method: Children ages 8-16 years with /[voiced alveolar approximant]/ distortions…

There is no one-to-one mapping between speech acoustics and individual speech sounds; instead, the acoustic cues produced for individual speech sounds show wide variability both within and across talkers. Nonetheless, listeners perceive the speech of familiar and novel talkers with ease. It is theorized that listeners achieve this feat by…

Recent findings have revealed that very preterm neonates already show the typical brain responses to place of articulation changes in stop consonants, but data on their sensitivity to other types of phonetic changes remain scarce. Here, we examined the impact of 7-8 weeks of extra-uterine life on the automatic processing of syllables in 20 healthy…

Purpose: While there has been mounting research centered on the diagnosis of childhood apraxia of speech (CAS), little has focused on differentiating CAS from pediatric dysarthria. Because CAS and dysarthria share overlapping speech symptoms and some children have both motor speech disorders, differential diagnosis can be challenging. There is a…

Purpose: This study aimed to (a) relate temporal patterning of articulation to functional speech outcomes in neurologically healthy and impaired speakers, (b) identify changes in temporal patterning of articulation in neurologically impaired speakers, and (c) evaluate how these changes can be modulated by speaking rate manipulation. Method:…