Learning and consolidation of new words: an ERP study during production of newly learned words in adults
Guest researcher: Laura Kaczer
Supervisor: Niels O. Schiller
Word learning is a fundamental building block in the acquisition of language and has often been identified as one of the distinctive components of human language. An intriguing question is how these new words consolidate their status as long term memories, becoming familiar and meaningful units stored in our brains. Consolidation is classically defined as a time-limited process of neuronal plasticity following a learning experience during which initially fragile memory traces become stabilized.
My current project is focused on the study of learning and consolidation of new words in adults, using ERPs and including the task of word production. Most studies in the area of word production use words that are already well-established in the memory system, and therefore it would be of interest to examine what happens after novel words are learned and subsequently retrieved. Thus, my objective is to analyze the dynamics of the changes in the overt production of newly learned word and address its neural correlates, in order to define the actual establishment of a new word as a long memory trace.
Neural correlates of vocal learning in songbirds and humans
PhD students: Anne van der Kant
Supervisors: Niels Schiller (LUCL), Claartje Levelt (LUCL) and Annemie Van der Linden (Bio-Imaging Lab, Antwerp)
This projects investigated the neural substrates of vocal learning in a comparative perspective, studying both humans and songbirds. The human studies were carried out at the LIBC language using functional MRI to address how neural activation during grammar learning differs between children and adults and how individual differences in artificial grammar learning success are reflected in neural activation.
Although we all learn our native language, some of us have more trouble learning a new grammar than others. Earlier studies have suggested that the age at which we learn a new language is very important for learning success. By investigating brain activation in children and adults during learning of a new grammar, I hope to find why children learn new languages with less effort compared to adults and how brain activation during learning is related to grammar learning success.
Plural as value of Cushitic gender: a psycholinguistic study
PhD students: Mulugeta Tsegaye
Supervisors: Prof. dr. Maarten Mous (LUCL) and prof. dr. Niels O. Schiller (LUCL)
Gender and number are intriguingly related in Cushitic languages. Although masculine and feminine are the accepted gender values across all Cushitic languages, there is evidence suggesting a third gender value in some Cushitic languages.
In contrast to other languages that have three-way gender distinction systems, this third value is not neuter in Cushitic. In terms of agreement, this third gender value requires the same agreement pattern as the third person plural. As a result, it is called "plural" gender. Two conflicting hypotheses have been put forward to analyze the gender systems of Cushitic languages. The first one comes from Corbett and Hayward (1987), in which only two gender values are recognized and the third value is analyzed as part of the number feature. The second one is the position taken in most descriptive studies on Cushitic languages and argued for in Mous (2008), in which three gender values are recognized and the so-called "plural" gender is treated as proper gender value. Thus, this third value "plural" raises the question whether nouns with this value are represented and processed only as part of the number feature or whether "plural" is a proper gender value. We are examining this issue by applying a picture-word interference (PWI) tasks to Cushitic languages (namely Konso and Bayso, lowland east Cushitic languages of Ethiopia).
Second language acquisition of prosody
PhD student: Amanda post da Silveira
Supervisors: Vincent van Heuven, Niels O. Schiller, Johanneke Caspers and Claartje Levelt
At the LUCL I am investigating second language acquisition of prosody. My research is funded by the program Monesia-Erasmus Mundus. I am currently performing behavioral tests to investigate the mechanism of L2 prosody processing assuming theword as a central unit in the structuring of L2 multi-dimensional linguistic knowledge.
I follow the tenets of connectionist modeling which have been proving that phonology, orthographic and semantic representations are co-defining representations of words that may be analyzed both sequentially (in terms of phonemic and graphemic sequence of a word form) and iconically (in the sense that the system recognizes de acoustic and/or visual form and automatically matches it to a template from the L1 or L2 lexicon) by the dynamic L1-L2 system. Similarly, semantic forms also activate semantically related nodes, as well as their respective phonological and orthographic forms. Given this background, we hypothesize that words that are similar in form between L1 and L2 are likely to carry more prosodic transfer from L1 to L2 and vice versa. I intend to use many L1-L2 language pairs, but my main interest is to give an account for the acquisition of L2-English prosody by native speakers of L1-Brazilian Portuguese.
Picture: A Parallel Distributed Processing (PDP) 'triangle' model by Seidenberg & McClelland’s (1989)
Neural mechanisms and brain structures underlying individual differences in acquisition of vocabulary and grammar of an artificial language. A neurolinguistic study of language aptitude.
PhD student: Olga Kepinska
Supervisors: Johanneke Caspers and Niels O. Schiller
In my research I investigate language aptitude, a specific talent for learning foreign languages that has been extensively studied within the field of second language acquisition. In my project I approach it from a neurolinguistic perspective, looking into how, in terms of neural correlates, highly skilled learners differ from average ones on analytical and memory component of language aptitude.
There are large differences in the way individual human brains work and are built. For example, the size of different brain structures, the number of neurons used to perform certain functions and the integrity of white matter (bundles of fibres connecting different parts of the cortex) vary from person to person. Recent studies show that some of these inter-individual differences correlate with specific cognitive tasks, such as language learning. People differ substantially in their ability to learn languages which may be linked to the diversity of human brains. Despite the recent technological advances in neurolinguistic research, it is still largely unknown how success in foreign language learning can be accounted for in terms of its neural correlates, and why some people are faster and better language learners than others. The aim of my project is therefore to enrich insights into the neural mechanisms and brain structures underlying individual differences in foreign language acquisition. To this end I make use of neuroimaging techniques such as fMRI and DTI combining these with behavioural measures such as language aptitude tests.
Picture: DTI (Diffusion Tensor Imaging) image of brain’s white matter tracts with the left Arcuate Fasciculus in blue.
The time course of orthographic and phonological facilitation in Chinese speech production (China Scholarship Council).
PhD student: Man Wang
Supervisors: Yiya Chen and Niels O. Schiller
My current research project is “Orthographic and phonological facilitation in Mandarin Chinese word production”, granted by NWO and CSC.
Orthographic and phonological facilitation effect, together with semantic interference effect are two effects observed in a picture-word interference (PWI) paradigm. PWI, widely used to study the cognitive process involved in speech production, is a variant of the Stroop task. In a PWI task, a participant is asked to name a picture and to ignore a superimposed distractor word. Because in alphabetic languages, the orthographic and phonological similarities are confounded, as a logographic language, Chinese has been employed the study these two effects in isolation. The current research aims to indentify the time course as well as the relative contribution of these two effects in the process of speech production.
Picture: A functional model of picture naming with word distractors in Chinese (Zhao, La Heij & Schiller, 2012)
Conceptual accessibility effects on sentence production in Tarifiyt Berber.
PhD student: Eleanor Dutton
Supervisor: Niels O. Schiller
Previous research has demonstrated for a variety of languages how the relative conceptual accessibility of referents affects sentence planning and production. For example, when describing a situation where the patient argument is more easily accessible than the agent, speakers are more likely to use grammatical structures which give prominence to the patient - such as passives in English or object-initial actives in Spanish.
The more accessible referent may receive a higher grammatical function, or an earlier position in the sentence, or both. However, to understand how universal cognitive principles such as accessibility interact with language-specific features, we must investigate a range of language types. My research will look at these effects in a Berber language, Tarifiyt. Tarifiyt is traditionally analysed as having basic verb-initial (VSO) word order, with SVO and OVS orders also possible. How does manipulating accessibility affect structural choice in a language with this profile? Tarifiyt has a passive, but this does not allow expression of the agent. This means that an initial choice to assign the patient to subject function constrains the later possibility of expressing the agent. But how far ahead does the processor look before initiating production? My project will aim to address these questions as well as promoting a linguistically diverse perspective in psycholinguistics.
Tapping into semantic recovery: an event-related potential study on the processing of gapping
PhD student: Bobby Ruijgrok
Supervisors: Crit Cremers, Niels O. Schiller and Lisa Cheng
This project aims to investigate the underlying (neurocognitive) linguistic processes of ellipsis resolution, particularly gapping. The neuroscientific technique "event-related brain potentials" (ERPs) is applied to determine the time-course of ellipsis resolution. Ellipsis is an omnipresent phenomenon in the world's languages and an adequate tool to examine non-lexical processing of meaning.
To interpret (1) a process of semantic recovery is required while processing the right conjunct.
(1) John likes bananas, and Sally pears.
In (1) the message of the right conjunct is that Sally likes pears; she did not - for example - steal them. Hence, somehow missing elements are retrieved. The question is what neural correlates constitute the resolution process. Using syntactic and semantic variables in several experiments in both the visual and auditory domain we will try to establish this.
This project is funded by an NWO 'PhD in the Humanities'-grant.
A psycholinguistic model for phonological development
PhD student: Margarita Gulian
Supervisors: Claartje Levelt and Niels O. Schiller
In my research I investigate the acquisition of onset cluster words like the word trein (train) by two-year-old Dutch children. In this I pay attention to both production and perception of onset clusters. So far I have found that in production children leave acoustic traces in their reduced cluster words. This is when they say tein for trein, koop for knoop (button) and choen for schoen (schoe). Regarding their perception, I have found that two-year-olds have trouble perceiving the difference between a cluster word (trein) and a simplified form of this cluster word (tein) but they can perceive the difference between the simplified (choen) and the complex form (schoen). These findings are striking with respect to how they relate to the question of storage of complex onset words in the child mental lexicon. On the one hand, acoustic traces point to a more detailed specification of the stored word than suggested from the surface form (tein), on the other hand, the failure to perceive the difference between trein and tein points to a less specified stored form. In order to shed more light on this controversy another perception study is under development.
Grammar induction: the influence of sample characteristics of the stimuli
PhD student: Jun Lai
Supervisors: Fenna Poletiek and Niels O. Schiller
How do children acquire the highly complex grammatical rules of their language? Linguistic theories (Chomsky, 1980) claim that children master natural grammar by means of an inborn language device.
Empirical psychological studies and computational studies, however, have indicated that grammar induction could be achieved from experience (Reber 1967; Elman 1991). The latter indication was further supported by studies of statistical learning and information sampling.
In the present project we look at how simple sample characteristics of the linguistic stimulus environment might help inducing grammar knowledge. Using the traditional Artificial Grammar Learning paradigm (Reber, 1967), we manipulate aspects of the input sample, such as the ordering of the stimuli (Lai & Poletiek, 2011), their frequency distribution, and the sample size. Though the effect of such sample characteristics is theoretically very straightforward, as we show, it is the first time that these sample characteristics are systematically studied in AGL-experiments. Their effects shown in the context of artificial language, may contribute to the understanding of natural grammar acquisition occurring under similar input sample conditions.