A Semantic Model to Study Neural Organization of Language in Bilingualism

Abstract

A neural network model of object semantic representation is used to simulate learning of new words from a foreign language. The network consists of feature areas, devoted to description of object properties, and a lexical area, devoted to words representation. Neurons in the feature areas are implemented as Wilson-Cowan oscillators, to allow segmentation of different simultaneous objects via gamma-band synchronization. Excitatory synapses among neurons in the feature and lexical areas are learned, during a training phase, via a Hebbian rule. In this work, we first assume that some words in the first language (L1) and the corresponding object representations are initially learned during a preliminary training phase. Subsequently, second-language (L2) words are learned by simultaneously presenting the new word together with the L1 one. A competitive mechanism between the two words is also implemented by the use of inhibitory interneurons. Simulations show that, after a weak training, the L2 word allows retrieval of the object properties but requires engagement of the first language. Conversely, after a prolonged training, the L2 word becomes able to retrieve object per se. In this case, a conflict between words can occur, requiring a higher-level decision mechanism.

Learning the lexical aspects of a second language at different proficiencies: A neural computational study

“…In this work we implemented two models: the first named a posteriori the “Basal Model” (Ursino et al, 2010) does not include any direct link between words in the lexical area. It is worth noting that this model structure resembles the “conceptual mediation model” proposed by Potter et al (1984).…”

“…In a recent paper (Ursino, Cuppini & Magosso, 2010) we presented a preliminary simple model of bilingualism, which assumes an inhibitory competition between L1 and L2. In the following, this will be named the Basal Model .…”

Working memory in multilingual children: Is there a bilingual effect?

“…This joint activation of several language systems in the bilingual mind creates lexical conflict between competing responses. It has been argued that mechanisms of cognitive control are needed to resolve this conflict by maintaining activation of the relevant language in addition to suppressing interference from the nontarget language (Bialystok, 1999;Ursino, Cuppini, & Magosso, 2010). In the light of increasing neuropsychological evidence demonstrating that the human brain adapts to repeated activity and environmental experience (Jaeggi, Buschkuehl, Jonides, & Perrig, 2008;Klingberg, Forssberg, & Westerberg, 2002), it has been suggested that the constant use of cognitive control to resolve linguistic conflict may boost performance on tasks that rely on this particular mechanism.…”