Language acquisition can be approached using two complementary strategies :
- a prospective strategy : study the initialcognitive state of the child who begins to acquire the language and, in chronological order, the subsequent cognitive states in development ;
- a retrospective strategy : starting from the study of the stablecognitive state, the adult knowledge of the language, go backwards in development and ask the question of when and how the child acquired the properties we observe.
The first strategy provides direct information on the child's initial language skills and enables developmental milestones to be tracked (Guasti, 2016). The second strategy provides an immediate measure of the cognitive task with which the child is confronted.
After several decades of formal linguistics studies, we now have precise models of the adult grammatical knowledge system, models that reveal in detail the complexity of this system. It is therefore natural to use these models as a starting point for the study of acquisition, in order to address retrospectively the development of linguistic abilities.
In this lecture, after briefly reviewing some key findings from experimental studies of the child's initial cognitive state, I adopt the retrospective strategy by first presenting some crucial aspects of adult language competence, and then illustrating current knowledge about the acquisition of these aspects.
The series of seminars held immediately after the lectures enriched and broadened the perspective with presentations by leading specialists in the experimental study of the initial cognitive state, children's brain imaging, language development, bilingualism and language pathologies.