Languages, Literatures, & Cultures Theses and Dissertations

Permanent URI for this collectionhttp://hdl.handle.net/1903/2785

Browse

Subject: search.filters.subject.Cognitive psychology

Search Results

Now showing 1 - 7 of 7
  • Thumbnail Image
    Item
    Simply (neuro-)stimulating: The effects of transcutaneous vagus nerve stimulation on phonological and lexical tone learning indexed by behavior and pupillometry
    (2021) Pandza, Nicholas Balint; Gor, Kira; Second Language Acquisition and Application; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Mandarin lexical tone learning has repeatedly been identified as a difficult linguistic feature for non-native speakers of tonal languages like English, even for native English learners of Mandarin at high proficiencies (e.g., Pelzl et al., 2019b). Sound perception training has been shown to help native English speakers perceive lexical tone differences, but acquiring lexical tone as a feature still remains difficult, even after as many as 18 training sessions (Bowles et al., 2016; Chandrasekaran et al., 2010; Li & DeKeyser, 2017; 2019; Liu & Chandrasekaran, 2013; Wang et al., 1999; 2003; Wong et al., 2011; Wong & Perrachione, 2007). While much of the tone learning literature has focused on different training interventions to overcome learning plateaus, another type of intervention that could augment learning is non-invasive neurostimulation. Transcutaneous auricular vagus nerve stimulation (taVNS) is a type of safe, non-invasive neurostimulation that delivers electrical current to the ear canal that has been shown to enhance cognition and learning (e.g., Jacobs et al., 2015). This dissertation investigated taVNS and its potential impact as tool to enhance Mandarin tone learning. Participants in three groups, peristim taVNS, priming taVNS, and a sham taVNS control participated in a double-blind two-day Mandarin phonological and lexical tone training study. Behavioral data including accuracy and reaction time were collected, as was physiological data in the form of pupillometry due to its ties both to cognitive effort and the most well-studied taVNS mechanism of action, the production of norepinephrine. Active taVNS groups received stimulation before or during multiple training and testing tasks across the two days. This body of work revealed: (1) priming and peristim administrations of taVNS differentially facilitated vocabulary learning of words with Mandarin tone, (2) priming and peristim administrations of taVNS differentially facilitated learning of new phonological tone categories, and (3) the effects of individual differences were substantially and differentially impacted by priming and peristim administrations taVNS, all results compared to a sham control. The evidence herein supports the potential of taVNS as a practical treatment intervention for enhancing language learning and reveals a number of considerations for its use and implementation to be explored in future research.
  • Thumbnail Image
    Item
    CROSS-LINGUISTIC DIFFERENCES IN THE LEARNING OF INFLECTIONAL MORPHOLOGY: EFFECTS OF TARGET LANGUAGE PARADIGM COMPLEXITY
    (2020) Solovyeva, Ekaterina; DeKeyser, Robert M.; Second Language Acquisition and Application; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Inflectional morphology poses significant difficulty to learners of foreign languages. Multiple approaches have attempted to explain it through one of two lenses. First, inflection has been viewed as one manifestation of syntactic knowledge; its learning has been related to the learning of syntactic structures. Second, the perceptual and semantic properties of the morphemes themselves have been invoked as a cause of difficulty. These groups of accounts presuppose different amounts of abstract knowledge and quite different learning mechanisms. On syntactic accounts, learners possess elaborate architectures of syntactic projections that they use to analyze linguistic input. They do not simply learn morphemes as discrete units in a list—instead, they learn the configurations of feature settings that these morphemes express. On general-cognitive accounts, learners do learn morphemes as units—each with non-zero difficulty and more or less independent of the others. The “more” there is to learn, the worse off the learner. This dissertation paves the way towards integrating the two types of accounts by testing them on cross-linguistic data. This study compares learning rates for languages whose inflectional systems vary in complexity (as reflected in the number of distinct inflectional endings)—German (lowest), Italian (high), and Czech (high, coupled with morpholexical variation). Written learner productions were examined for the accuracy of verbal inflection on dimensions ranging from morphosyntactic (uninflected forms, non-finite forms, use of finite instead of non-finite forms) to morpholexical (errors in root processes, application of wrong verb class templates, or wrong phonemic composition of the root or ending). Error frequencies were modeled using Poisson regression. Complexity affected accuracy differently in different domains of inflection production. Inflectional paradigm complexity was facilitative for learning to supply inflection, and learners of Italian and Czech were not disadvantaged compared to learners of German, despite their paradigms having more distinct elements. However, the complexity of verb class systems and the opacity of morphophonological alternations did result in disadvantages. Learners of Czech misapplied inflectional patterns associated with verb classes more than learners of German; they also failed to recall the correct segments associated with inflections, which resulted in more frequent use of inexistent forms.
  • Thumbnail Image
    Item
    Modeling the effects of entrenchment and memory development on second language acquisition
    (2019) Osthus, Peter Daniel; DeKeyser, Robert; Second Language Acquisition and Application; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    The observation that language learning outcomes are less consistent the older one becomes has motivated a large portion of second language acquisition research (e.g., Hartshorne, Tenenbaum, & Pinker, 2018; DeKeyser, 2012). Hypotheses about the underlying mechanisms which lead to age-related declines are traditionally tested with human subjects; however, many hypotheses cannot be fully evaluated in the natural world due to maturational and environmental constraints. In these scenarios, computational simulations provide a convenient way to test these hypotheses. In the present work, recurrent neural networks are used to study the effects of linguistic entrenchment and memory development on second language acquisition. Previous computational studies have found mixed results regarding these factors. Three computational experiments using a range of languages were conducted to understand better the role of entrenchment and memory development in learning several linguistic sub-tasks: grammatical gender assignment, grammatical gender agreement, and word boundary identification. Linguistic entrenchment consistently had a negative, but marginal, influence on second language learning outcomes in the gender assignment experiment. In the gender agreement and word boundary experiments, entrenchment rarely affected learning outcomes. Starting with fewer memory resources consistently led to poorer outcomes across learning tasks and languages. The complexity of the learning task and the regularity of the formal cues present in the linguistic input affected outcomes. In the gender assignment experiment, the first language influenced second language outcomes, especially when the second language had fewer gender classes than the first language. These results suggest that the effects of entrenchment and memory development on second language learning may be dependent upon the language pairs and the difficulty of the modeling task.
  • Thumbnail Image
    Item
    Explicit and Implicit Cognitive Aptitudes, L2 Outcome Measures, and Learning of Morphosyntax under an Incidental Condition
    (2018) Maie, Ryo; DeKeyser, Robert M; Second Language Acquisition and Application; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    This study is the first to combine recent methodological advances to the measurement of explicit and implicit knowledge in an investigation of learning under incidental exposure. Participants were exposed to a semi-artificial language, Japlish, and subsequently tested as to the extent to which they had developed explicit and/or implicit knowledge. Subjective measures of awareness, objective measures of linguistic knowledge, and explicit and implicit cognitive aptitudes were employed to triangulate learning outcomes at two testing sessions. Overall results shed new light on the complexity of explicit and implicit learning under incidental conditions. Both learning types were confirmed in the experiment, but they occurred to a different degree and extent. Furthermore, the study identifies clear discrepancies among the four approaches to measuring explicit and implicit knowledge, with some being rigorous and others tending to underestimate or overestimate. The study calls for future research with more longitudinal and situated analyses of the phenomena.
  • Thumbnail Image
    Item
    TEMPORAL DISTRIBUTION OF PRACTICE AND INDIVIDUAL DIFFERENCES IN THE ACQUISITION AND RETENTION OF L2 MANDARIN TONAL WORD PRODUCTION
    (2017) Li, Man; DeKeyser, Robert M; Second Language Acquisition and Application; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    This dissertation investigated the effects of temporal distribution of practice (relatively massed vs. distributed) on the learning and retention of oral Mandarin tonal word production by native English-speaking adults within the theoretical framework of skill acquisition and retention theories. The present study focused on oral production of Mandarin two-syllable words as a function of temporal distribution of practice. It also explored whether the effects of this distribution differ depending on the type of knowledge to be acquired or retained (declarative word knowledge vs. skills in oral production) and on individual differences in cognitive aptitudes (including working memory, phonological short-term memory, declarative memory, procedural memory, and musical aptitude). Eighty native English-speaking adults who did not have any prior knowledge of a tonal language completed all sessions of the study and provided data for analysis. These participants were randomly assigned to four experimental conditions, i.e., Condition A with a 1-day ISI (intersession interval) and a 1-week RI (retention interval), Condition B with a 1-day ISI and a 4-week RI, Condition C with a 1-week ISI and a 1-week RI, and Condition D with a 1-week ISI and a 4-week RI. Each participant came in for five sessions. All participants completed a set of cognitive aptitude tests and underwent the same number and content of training sessions, which differed only on training or testing schedules. The results showed that the effects of ISI and RI differed depending on the type of knowledge/skill to be retained, declarative versus procedural. For the retention of declarative knowledge, RI had a robust effect: the longer the RI, the worse the retention. Spacing, or distributed practice seemed to improve long-term retention of declarative knowledge; however, this ISI effect was much weaker. With regard to procedural knowledge retention, ISI seems to play a role, but not RI, and it was massed practice that had an advantage over distributed practice. Musical aptitude, working memory, and declarative memory ability were found to play facilitative roles in L2 learning of Mandarin tonal word productions. Procedural memory ability was found to interact with ISI and RI for various RT outcome measures.
  • Thumbnail Image
    Item
    THE RELATIVE SIGNIFICANCE OF SYNTACTIC KNOWLEDGE AND VOCABULARY KNOWLEDGE IN SECOND LANGUAGE LISTENING COMPREHENSION
    (2016) Vafaee, Payman; Ross, Steve; Second Language Acquisition and Application; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    The main purpose of the current study was to examine the role of vocabulary knowledge (VK) and syntactic knowledge (SK) in L2 listening comprehension, as well as their relative significance. Unlike previous studies, the current project employed assessment tasks to measure aural and proceduralized VK and SK. In terms of VK, to avoid under-representing the construct, measures of both breadth (VB) and depth (VD) were included. Additionally, the current study examined the role of VK and SK by accounting for individual differences in two important cognitive factors in L2 listening: metacognitive knowledge (MK) and working memory (WM). Also, to explore the role of VK and SK more fully, the current study accounted for the negative impact of anxiety on WM and L2 listening. The study was carried out in an English as a Foreign Language (EFL) context, and participants were 263 Iranian learners at a wide range of English proficiency from lower-intermediate to advanced. Participants took a battery of ten linguistic, cognitive and affective measures. Then, the collected data were subjected to several preliminary analyses, but structural equation modeling (SEM) was then used as the primary analysis method to answer the study research questions. Results of the preliminary analyses revealed that MK and WM were significant predictors of L2 listening ability; thus, they were kept in the main SEM analyses. The significant role of WM was only observed when the negative effect of anxiety on WM was accounted for. Preliminary analyses also showed that VB and VD were not distinct measures of VK. However, the results also showed that if VB and VD were considered separate, VD was a better predictor of L2 listening success. The main analyses of the current study revealed a significant role for both VK and SK in explaining success in L2 listening comprehension, which differs from findings from previous empirical studies. However, SEM analysis did not reveal a statistically significant difference in terms of the predictive power of the two linguistic factors. Descriptive results of the SEM analysis, along with results from regression analysis, indicated to a more significant role for VK.
  • Thumbnail Image
    Item
    Mix and Switch Effects in Bilingual Language Processing
    (2012) Koeth, Joel Todd; Jiang, Nan; Second Language Acquisition and Application; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    This study utilized a novel task design in an effort to identify the source of the second language processing advantage commonly reported in mixed language conditions, investigate switch cost asymmetry in non-balanced bilinguals, and identify task-related variables that potentially contribute to inconsistent results across studies with similar participant populations. Seventy highly-proficient Korean-English bilinguals completed modified picture naming, semantic categorization, and lexical decision tasks, as well as a cognitive control task designed to examine the potential relationship between lexical control and general cognitive control. While no significant relationship was found between lexical control and general cognitive control, several key task-related variables emerged with respect to mix and switch effects. Specifically, verbal production requirements and increased second language repetition effects significantly influenced results. Furthermore, this study revealed potential effects of semantic load as well as script differences in receptive tasks. Results from this study highlight several key variables that contribute to bilingual mix and switch effects, as well as task design-related considerations for future bilingual mix and switch studies.