An ERP Investigation on Adult Second Language Word Learning.
Yum, Yen Na.
Abstract: Accruing evidence has shown neural changes associated with second
language (L2) exposure in beginning L2 learners, however, gaps remain in our understanding
of these learning-related changes. Our studies used visually distinct languages to
complement other bilingual studies that use languages that are more similar to each other.
The first study in this dissertation (chapter 2) compared ... read moreviewers of different linguistic
expertise to investigate the visual processing of words compared to line drawings of
concrete objects using a semantic categorization task. We teased apart the processing of
Chinese words, English words, and pictures by controlling for gross visual differences
between these stimuli types, revealing ERP differences related to levels of visual
processing--script (English vs. Chinese), domain (pictures vs. words), and meaningfulness
(unknown Chinese words vs. known pictures). In chapters 3 through 5, we describe the neural
and behavioral changes that accompany initial word learning of an L2 of a different writing
system under tightly-controlled laboratory conditions. Chapter 3 is an investigation of the
emergence of L2 lexicality effects and how visual differences between L1 and L2 might
influence perception of lexicality in initial L2 learners. The study used a lexical
decision task with learned Chinese items and Chinese pseudowords and nonwords. Results
showed development of sensitivity to lexical status with L2 exposure as indexed by N400
effects. Chapter 4 addresses the question of how learning contexts affect behavioral and
neural changes in L2 learning. Since Chinese characters represent a new orthography, more
resources might be necessary to process their visual forms. This study compared learners
who learned L2 Chinese words visually and those who were presented with pronunciations of
L2 words in addition to the visual forms. Half of the visual group also did a character
copying task to augment their visual analysis of the L2 items and half of the auditory
group verbally repeated the pronunciations of the L2 words as additional phonological
training. Differences in learning outcome were observed both behaviorally and in ERP
activation, suggesting the importance of the type of language input. Chapter 5 examines the
question of learning speed and how it might relate to learning patterns. This study
contrasted the ERP data from participants who performed well in behavioral tasks and those
who did not perform as well. Distinct ERP patterns in the N170 and the N400 were found for
the two groups, which might be related to different strategy use for Chinese character
recognition. As a whole, the four articles in this dissertation present an investigation
into the cognitive and neural underpinnings of L2 learning in adults.
Thesis (Ph.D.)--Tufts University, 2013.
Submitted to the Dept. of Psychology.
Advisor: Phillip Holcomb.
Committee: Katherine Midgley, Jonathan Grainger, Holly Taylor, and Marianna Eddy.
Keywords: Cognitive psychology, and Physiological psychology.read less