The organization of the bilingual mental lexicon

Gulan, Tanja. (2016). The organization of the bilingual mental lexicon. PhD Thesis. Filozofski fakultet u Zagrebu, Department of Psychology.
(Poslijediplomski doktorski studij psihologije) [mentor Domijan, Dražen].

Preview

PDF (Croatian) Download (2MB) | Preview

Abstract

One of the prerequisites for successful and meaningful communication with other people includes the knowledge of words and their meanings stored in the long term memory. The part of long term memory that refers to the knowledge of words and their features, such as meaning, form, phonology and syntax is known as the mental lexicon. In accordance with this, individuals who have knowledge of two languages store words from two languages in their mental lexicon. In the field of research of bilingual memory the main questions are how two languages are stored and organized in the mind of bilinguals, and how one manages to keep those languages separated while understanding and producing language? The vast majority of bilingual mental lexicon models assumes that the mental representation of language(s) is composed of two levels; the lexical level which refers to word form, and the conceptual level which refers to word meaning(s). Furthermore, it is considered that there are, in the bilingual mental lexicon, two distinct lexical storages for each language and one shared conceptual storage. Another prominent issue in this area of research refers to lexical access, i.e. the process of entering the mental lexicon and retrieving word characteristics and meaning. There is a high consensus among researchers that the nature of lexical access in bilinguals is non-selective. In other words, when one sees or hears a word the word activates instances from both lexical storages regardless of the language, which means that the non-target language cannot be inhibited. In this research the emphasis is on the nature and strength of the lexical and conceptual links between conceptual storage and the two lexical ones, as well as the influence of semantic and phonological contextual factors on word processing and production. Seeing that bilingual speakers must maintain control over two languages in order to avoid language mixing, it is assumed that they have better executive control. In accordance with this, the bilingual Stroop task was administrated in order to gain insight into one measure of cognitive control. In order to test these aforementioned research problems six experiments were conducted. Two of which examined the speed of written word recognition and four that required language production. This research included several research paradigms, such as picture naming, priming, a lexical decision task, translation, translation recognition, Stroop and Stroop like tasks. The participants were fluent adult Croatian-English unbalanced bilinguals who differed in their level of proficiency in the English language (N = 86). The sample consisted of psychology students and students of the English language and literature who received compensation for their participation. All participants filled out a questionnaire about their history of language learning and underwent English vocabulary testing. Their participation in these experiments consisted of three sessions in the laboratory. Unlike previous research regarding the organization of the bilingual mental lexicon this research used two distinct word classes, namely nouns and verbs. The results of this research show that the strength of lexical and conceptual links does not follow the same pattern when tested on verbs and nouns, which indicates that either those types of words are processed and stored differently in the brain or that existing models of bilingual memory do not account for such differences. Moreover, the effects of semantically related contextual factors were task dependent, i.e. in the word recognition task they had a facilitatory effect, while showing an inhibitory effect in the word production task. Although the differences between the two groups of subjects at different level of proficiency in English are mainly not obtained, the differences within each group of subjects indicated differences. This indicates that the structure and the strength of lexical and conceptual links differs with respect to the level of proficiency. Finally, it has been concluded that an adequate model of the mental lexicon of bilinguals that could explain the obtained results with respect to language understanding and language production is still lacking.

Actions (login required)

View Item