Speech is a complex, redundant and variable signal happening in a noisy and ever changing world. How do listeners navigate these complex auditory scenes and continuously and effortlessly understand most of the speakers around them? Studies show that listeners can quickly adapt to new situations, accents and even to distorted speech. Although prior…

This review describes a computational approach for modeling the development of speech motor control in infants. We address the development of two levels of control: articulation of individual speech sounds (defined here as phonemes, syllables, or words for which there is an optimized motor program) and production of sound sequences such as phrases…

Working Memory (WM) is an essential concept of cognitive science since many aspects of human learning depend on it. Primarily proposed by Baddeley and Hitch (1974) and developed by Baddeley (1986), the concept of WM comprises the number of subsystems involved during the process and the considerable emphasis on its key role in cognitive tasks such…

Collaborative problem solving (CPS) is a crucial 21st century skill; however, current technologies fall short of effectively supporting CPS processes, especially for remote, computer-enabled interactions. In order to develop next-generation computer-supported collaborative systems that enhance CPS processes and outcomes by monitoring and…

To confirm the role of social factors in mediating cognitive processes, this systematic replication study seeks to extend the generalizability of an exploratory study (McDonough, Crowther, Kielstra & Trofimovich 2015) that reported a positive association between eye gaze and second language (L2) speakers' responses to recasts. For this…

Choosing specific implementational details is one of the most important aspects of creating and evaluating a model. In order to properly model cognitive processes, choices for these details must be made based on empirical research. Unfortunately, modelers are often forced to make decisions in the absence of relevant data. My work investigates the…

This dissertation proposes a dynamical computational model of the timecourse of phonological parameter setting. In the model, phonological representations embrace phonetic detail, with phonetic parameters represented as activation fields that evolve over time and determine the specific parameter settings of a planned utterance. Existing models of…

Chinese EFL learners may have difficulty in speaking fluent and accurate English, for their speaking competence are likely to be influenced by cognitive, linguistic and affective factors. With the aim to enhance those learners' oral proficiency, this paper first discusses three effective models of teaching English speaking, and then proposes a…

This study explores the potential for automated indices related to speech delivery, language use, and topic development to model human judgments of TOEFL speaking proficiency in second language (L2) speech samples. For this study, 244 transcribed TOEFL speech samples taken from 244 L2 learners were analyzed using automated indices taken from…

Narrative discourse is an essential component of day-to-day communication, but little is known about narrative in Lewy body spectrum disorder (LBSD), including Parkinson's disease (PD), Parkinson's disease with dementia (PDD), and dementia with Lewy bodies (DLB). We performed a detailed analysis of a semi-structured speech sample in 32 non-aphasic…

The Gesture as Simulated Action (GSA) framework (Hostetter & Alibali, 2008) holds that representational gestures are produced when actions are simulated as part of thinking and speaking. Accordingly, speakers should gesture more when describing images with which they have specific physical experience than when describing images that are less…

This study explores the potential for automated indices related to speech delivery, language use, and topic development to model human judgments of TOEFL speaking proficiency in second language (L2) speech samples. For this study, 244 transcribed TOEFL speech samples taken from 244 L2 learners were analyzed using automated indices taken from…

Audiovisual speech perception provides an opportunity to investigate the mechanisms underlying multimodal processing. By using nonspeech stimuli, it is possible to investigate the degree to which audiovisual processing is specific to the speech domain. It has been shown in a match-to-sample design that matching across modalities is more difficult…

We report two sets of experiments showing that the large individual variability in language learning success in adults can be attributed to neurophysiological, neuroanatomical, cognitive, and perceptual factors. In the first set of experiments, native English-speaking adults learned to incorporate lexically meaningfully pitch patterns in words. We…

Working memory is believed to play a central role in almost all domains of higher cognition, yet the specific mechanisms involved in working memory are still fiercely debated. We describe a neuroimaging experiment with functional magnetic resonance imaging (fMRI) and a companion behavioral experiment, and in both we seek to adjudicate between…