Origins of Semantic Composition in Early Cognitive Development

Spedbarn begynner å forstå språk før de sier sine første ord. Språkforståelse innebærer en evne til å danne forbindelser mellom enkle konsepter. For eksempel er 'rød ball' resultatet av kombinasjonen av 'rød' og 'ball'. Når lærer barn det? Hvordan utvikles denne kapasiteten: plutselig eller gradvis? I dette prosjektet undersøkte vi dette problemet. Vi kombinerte innsikter fra logikk, psykologi og lingvistikk med eksperimentelle metoder fra nevrovitenskap.

The project has generated several high-impact publications, some of which are already attracting citations and mentions. A significant chunk of the research from this project is currently being finalised, with several papers in-progress or under-review. The full impact of the project is likely to grow in the coming years also as a consequence of new output.

Semantic composition is the ability to bind together two or more lexical concepts. For example, RED and BRICK may be unified into the compound RED BRICK. In adults, this ability is tied to the language-specific capacity to combine words into grammatical phrases. For example, in English 'red' and 'brick' may be combined into 'red brick', but not into 'brick red'. In other languages, the order of the adjective and noun may be different. However, infants are able to understand and construct simple semantic compounds before they can encode them in speech, and before they can represent the correct word order in the grammar of the languages they are acquiring. This project aims to track the origin and development of semantic composition in the first two years of life, prior to the acquisition of complex grammatical skills. The proposed research is based on the hypothesis, supported by previous work, that there are three key developmental precursors of semantic composition. (1) Cross-modal priming (present at 9 months): the ability to relate semantically sequential information from different modalities (e.g., the spoken word 'dog' and the sight or the picture of a dog, and vice versa). (2) Cross-modal integration (from 14 months): the ability to relate information delivered simultaneously in different modalities (e.g., the spoken word 'dog' and the sight or the picture of a dog). (3) Lexical semantic priming (from 18 months): or the capacity to relate the meaning of words presented in close succession (e.g., 'dog' and 'bark'). We plan to conduct a longitudinal study of Norwegian infants and toddlers from 6 to 36 months of age, with a compact battery of tests including cross-modal priming and integration, lexical priming and sentence processing, using the N400 effect in event-related potentials (ERPs) as a measure of semantic processing in each case. We will use the N400 as a predictor of individual differences in linguistic and logical skills in the second and third years.