What makes some sentences more difficult to process, and why? Memory- and expectation-based theories both attempt to explain sentence processing difficulties, and decades of sentence processing literature have found evidence in support of both theories. This dissertation further investigates these theories of sentence processing by exploring…

It is standardly believed that some occurrences of expressions designate singularly, while other occurrences of expressions designate plurally. For instance, the singular expression the student may be used on an occasion to talk about one particular student, while the plural expression the students may be used on an occasion to talk about several…

Background: The most common cause of aphasia is a left middle cerebral artery stroke affecting the left perisylvian region of the brain. The perisylvian region is critical for supporting phonological processing, and damage to this region results in difficulty with retrieving and manipulating speech sounds. The impact of weakened phonology has been…

In this dissertation, I establish a research program that uses computational modeling as a testbed for theories of phonological learning. This dissertation focuses on a fundamental question: how do children acquire sound patterns from noisy, real-world data, especially in the presence of lexical exceptions that defy regular patterns? For instance,…

Speakers display considerable variability in language use and representations: they may have different pronunciations of the same word, different intended meanings for the same phrases, and different sets of syntactic constraints in their internalized grammars. Comprehenders adapt to such variability by constantly updating their expectations for…

The past thirty years have shown a rise in models of language acquisition in which the state of the learner is characterized as a probability distribution over a set of non-stochastic grammars. In recent years, increasingly powerful models have been constructed as earlier models have failed to generalize well to increasingly complex and realistic…

This dissertation interrogates the representation of syntactic locality constraints, specifically intervention locality, within child grammar. Our focal point is the Intervention Hypothesis, which suggests that children are governed by a strict version of featural Relativized Minimality, leading to comprehension difficulties when partial featural…

The strand of feedback research within the field of Instructed Second Language Acquisition (ISLA) examines the effects of feedback on the development of second language (L2) knowledge and learning behaviors. While findings often make claims about the relationship between feedback and language processing, much of this research has not measured…

The systems underlying incremental sentence comprehension are, in general, highly successful -- comprehenders typically understand sentences of their native language quickly and accurately. The occasional failure of the system to deliver an appropriate representation of a sentence is therefore potentially illuminating. There are many ways the…

Bilinguals are able to compose expressions across their languages with seeming ease. This phenomenon, commonly referred to as "code-switching," has challenged both theoretical models in linguistics as well as neurobiological models of language processing. And yet, our models of the bilingual brain and the language processing mechanism…

This dissertation investigates how parametric variation of linguistic properties leads to similarities and differences in language processing across the levels of words, grammatical features, and sentences. For a truly generalizable theory of psycholinguistics, the languages surveyed should not be constrained to English (Garnham, 1994; Norcliffe…

Formulaic expressions (FEs), such as conventional collocations (e.g., fresh air) and phrases (e.g., take a break), constitute a significant part of language use in our daily lives (Erman & Warren, 2000). FEs are defined as multiword units that holistically represent a single meaning, and they are likely stored and retrieved as unanalyzed…

Data-driven learning uncontroversially plays a role in human language acquisition--how large a role is a matter of much debate. The success of artificial neural networks in NLP in recent years calls for a re-evaluation of our understanding of the possibilities for learning grammar from data alone. This dissertation argues the case for using…

For many people, learning a second language as an adult is a challenging endeavor. Much interest in the study of adult second language learning has concerned the type of input that learners receive in their second language, with findings suggesting that second language learners are often exposed to a register of speech called 'foreigner talk' that…

This dissertation sheds light on some of the representations used in human language production. Language production consists of several distinct stages; in particular, we focus on the stages of lexical retrieval and grammatical encoding. Lexical retrieval involves retrieving the words required to express the intended meaning; grammatical encoding…