Plenary speakers
Prof. Agnieszka Otwinowska-Kasztelanic
Agnieszka Otwinowska-Kasztelanic is a Professor at the University of Warsaw, specializing in individual differences in language acquisition, bilingualism and multilingualism, cross-linguistic influence, and vocabulary learning. Using behavioural methods, she investigates how multilingual learners draw on their existing linguistic repertoires when acquiring new lexical systems. Her particular focus is on cognate vocabulary and the ways in which languages interact, support, or interfere with one another during L2 and L3 vocabulary acquisition. In addition to her research, Prof. Otwinowska-Kasztelanic is a teacher trainer and the author of course books and syllabuses for English language teaching.
Easy words, difficult words, and the multilingual mental lexicon
Nearly a quarter of a century after the publication of “The Multilingual Lexicon” (Cenoz, Hufeisen, & Jessner, 2003), L3 vocabulary acquisition still remains under-explored. While it is well established that cross-linguistic similarity can facilitate lexical acquisition in both L2 and L3, the precise mechanisms underlying L3 vocabulary learning are not fully understood. In particular, it remains unclear whether any degree of formal overlap with the L1 or L2 is sufficient to support learning, or whether L3 lexical development is jointly shaped by all previously acquired languages.
In this talk, I will examine current theoretical frameworks and empirical findings on L3 vocabulary acquisition, with a particular focus on cross-linguistic influence (CLI), which arises from the co-activation of multiple languages in the multilingual mind. Co-activation and CLI inevitably affect the processing and learning of new L3 lexical items. To address these issues, I review evidence from three strands of research: L3 word processing studies, cognate guessing tasks, and experimental word-learning paradigms. In addition, I will present data from experiments conducted in my lab, which investigated how cumulative similarity across L1, L2, and L3 can either facilitate word learning or impede it by triggering CLI-related spelling errors. Drawing on this body of evidence, I will discuss implications for the architecture of the multilingual mental lexicon, interpreted within the framework of the Parasitic Model (Hall & Ecke, 2003; Ecke, 2015).
Overall, the talk seeks to bridge psycholinguistic and applied linguistic perspectives on L3 vocabulary acquisition by highlighting factors that modulate the learning process. I will argue that L3 lexical development is best understood as a dynamic and cumulative process in which the multilingual mind exploits existing linguistic resources through co-activation and parasitic integration, with the magnitude of these effects moderated by proficiency levels and individual learner characteristics. The talk will conclude by outlining directions for future research, emphasizing the need for careful control of numerous variables influencing outcomes in L3 lexical studies. I will also consider some pedagogical implications for vocabulary instruction in multilingual classroom contexts.
Prof. Ludovica Serratrice
Ludovica Serratrice is Professor of Bi-Multilingualism at the University of Reading. Her research investigates how children acquire and use language in multilingual contexts, with a particular focus on bilingual and heritage language development. Her work examines how grammatical representations emerge and interact across languages, and how crosslinguistic influence shapes bilingual language development. Much of her research focuses on bilingual children growing up in immigrant and heritage language communities, exploring how factors such as language exposure, proficiency, and input structure affect the development of syntax, discourse, and language processing.
From parallel grammars to shared syntax: A developmental perspective on bilingual representations
Understanding how bilingual speakers represent two languages within a single cognitive system remains a central challenge in psycholinguistics. A long tradition of research using crosslinguistic syntactic priming has argued that bilinguals may develop shared syntactic representations across their languages. However, most of the evidence supporting this claim comes from studies of adult bilinguals, and much less is known about how such representations emerge developmentally or what kinds of structural information may be shared across languages in childhood.
In this keynote I argue that bilingual grammatical representations do not become shared all at once at the level of abstract syntax. Instead, evidence from a series of experimental studies with Polish–English bilinguals shows a developmental trajectory in which representations become integrated gradually across multiple levels of linguistic structure. Drawing on structural priming experiments with children, adolescents, and adults, I show that young bilinguals first develop robust language-specific syntactic representations within each language, as evidenced by strong within-language priming effects but limited crosslinguistic priming for structurally equivalent constructions.
At the same time, crosslinguistic priming can occur even when syntactic structures differ across languages, provided that constructions share deeper structural properties such as thematic role ordering. Comparisons across age groups indicate that more abstract, language-nonspecific syntactic representations emerge gradually with increased linguistic experience. Adolescents show limited evidence of shared syntax for less frequent constructions, whereas adults exhibit robust bidirectional crosslinguistic priming consistent with shared representations.
Taken together, these findings support a developmental model in which bilingual grammars become integrated progressively: from language-specific syntactic systems, to crosslinguistically linked representations of thematic and discourse structure, and ultimately to abstract shared syntax. This perspective reframes debates about shared representations in bilingualism and highlights the importance of a developmental perspective for understanding the architecture of bilingual grammars.
Prof. Guillaume Thierry
Guillaume Thierry is a Professor of Cognitive Neuroscience at Bangor University. His work spans a wide range of topics, including verbal and non-verbal dissociations, visual object recognition, colour perception, functional cerebral asymmetry, language-emotion interactions, developmental dyslexia, bilingualism, and language development in both children and adults. Using neuroscientific methods such as electroencephalography (EEG), eye-tracking, and neuroimaging, Prof. Thierry examines how the brain constructs meaningful representations of the world. Since 2005, he has received funding from the BBSRC, the ESRC, the AHRC, the European Research Council, and the British Academy. He now focuses on linguistic relativity and the philosophical question of mental freedom.
If having a second language is like having a second mind, what does having a third language entail?
Language shapes thought in ways that are both profound and largely unconscious. Speakers of different languages do not merely communicate differently — as Benjamin Lee Whorf hypothesised in the 1940s, they perceive and conceptualise the world differently. This keynote explores how the number of languages a speaker commands may multiply, complicate, or restructure perception and cognition. Drawing on recent neuroscientific evidence from Chinese-English and Polish-English bilinguals, we examine how a second language modulates access to first-language lexical representations, anchors conceptual processing of grammatical categories absent in the native language, reduces cognitive interference during creative ideation, and even shifts acceptance of foreign cultural norms at the level of implicit semantic processing. Taken together, these findings suggest that operating in a second language triggers in a vastly different cognitive mode rather than a merely a degraded version of native language processing. Against this backdrop, we ask what a third language may add (or subtract): does it amplify linguistic relativity effects, introduce new conceptual frames, or further reduce the speaker’s grip on native-language cognitive habits? Implications for multilingual cognition and language pedagogy are discussed.