L1 lexical attrition is the decline of L1 lexical-semantic abilities due to reduced L1 exposure and/or L2 interference. Semantic fluency tasks are central in this research, but traditional analyses are often inconclusive.

To address this, we employed an innovative network science approach to investigate the bilingual lexicon's structural properties. Semantic fluency data were collected from immersed/non-immersed late bilinguals with comparable L2 proficiencies.

Our results indicate that L2 immersion led to more integrated and efficient L2 networks. Crucially, immersion also resulted in L1 attrition (only evident in the network analysis). Immersed participants exhibited less densely connected and sparser L1 networks. Furthermore, network measures suggest that L1 lexical attrition occurs gradually, initially impacting network interconnectivity, while information flow and community structure remain more stable.

Drawing from these insights, we introduce the Lexical Attrition Foundation (LeAF) framework, offering a network-based perspective on lexical attrition development and laying the groundwork for future research.

Previous studies analysing the differences in emotionality in first and second language suggest that affective content of lexical items is modulated in certain contexts. This paper investigates the differences in valence and arousal ratings for 300 early words, in both oral and written modalities, through speakers’ subjective appraisal of words given by two immersion groups of Spanish late bilinguals (Chinese and European) compared with a group of native speakers. The main goal of our study is to identify the lexical areas where variability occurs, regarding to a set of affective (emotional charge and intensity), grammatical (nouns, adjectives and verbs) and semantic (concreteness) features of words. Our results show that valence is the dimension where the greatest variability is observed between native and bilinguals, although the influence of the independent factors differs considerably. Besides, arousal yields illuminating data regarding the grammatical category of words and differentiation between the groups of participants.

A claim fundamental to the revised hierarchical model (Kroll & Stewart, 1994) was that concepts did not mediate backward translation, based on their findings of a category interference effect in forward translation in relatively fluent bilinguals but no category effect in backward translation. This study hypothesized that there was a category facilitation effect in L2-to-concept, which counterbalanced the category interference effect in concept-to-L1, resulting in an overall L2-to-L1 null category effect.

In a novel English word-pair semantic comparison task, participants were presented with a sequence of English word-pairs, and judged which word's real-world referent was bigger in size. Results found a significant category facilitation effect in both L2-to-concept for young Chinese adults and L1-to-concept for young English adults when increasing the number of trials. The findings help explain why Kroll and Stewart's finding of an overall L2-to-L1 null category effect cannot be evidence against concept mediation in backward translation.

The study examined granularity of lexical partitioning of the blue area in speakers of English, which encodes the term blue; Russian, which encodes two terms, sinij [dark/navy blue] and goluboj [light/sky blue]; and Ukrainian, which encodes the terms synij [dark/navy blue] and blakytnyj and golubyj [light/sky blue]. Five groups of participants took part in the study: (1) 30 L1 speakers of English, (2) 30 L1 speakers of Russian, (3) 30 Russian–English bilinguals, (4) 30 English–Russian bilinguals, and (5) 25 Ukrainian–Russian–English trilinguals. Quantitative and qualitative analyses revealed that L1 Russian speakers referred to different types of blue significantly more frequently than all other groups, while bilinguals patterned with L1 English speakers. These findings suggest that classroom exposure to L2 Russian does not make the distinction between sinij and goluboj communicatively relevant for L1 English speakers and that everyday use of L2 English may trigger attrition of the contrast in L1 Russian.

We investigated the influence of word class and translation ambiguity on cross-linguistic representation and processing. Bilingual speakers of English and Spanish performed translation production and translation recognition tasks on nouns and verbs in both languages. Words either had a single translation or more than one translation. Translation probability, as determined by normative data, was the strongest predictor of translation production and translation recognition, after controlling for psycholinguistic variables. Word class did not explain additional variability in translation performance, raising the possibility that previous findings of differences between nouns and verbs might be attributed to the greater translation ambiguity of verbs relative to nouns. Proficiency in the second language was associated with quicker and more successful production of translations for ambiguous words, and with more accurate recognition of translations for ambiguous words. Working memory capacity was related to the speed of recognizing low probability translations for ambiguous words. These results underscore the importance of considering translation ambiguity in research on bilingual lexical and conceptual knowledge.