Component 2 – Spoken language acquisition: Development and extension of vocabulary (lexis)

This topic explores how children acquire and expand their vocabulary, focusing on the development of lexis from infancy through adolescence. You'll examine key theories such as Jean Aitchison's three-stage model (labelling, packaging, network building) and Eve Clark's principles of contrast and conventionality. Understanding these frameworks is essential for analysing how children move from single words to complex semantic networks, and how they learn to categorise and differentiate meanings. This component also covers the role of fast mapping, overextension, underextension, and the influence of input from caregivers.

Mastering this topic is crucial because vocabulary development underpins all later language skills, including reading comprehension and academic success. In the exam, you'll be asked to apply theories to data (e.g., child utterances or caregiver speech) and evaluate competing explanations. You'll also need to discuss factors like socioeconomic background (Hart & Risley's word gap) and the impact of bilingualism. This knowledge directly links to other components, such as language change and child phonology, making it a cornerstone of the A-Level course.

By the end of this topic, you should be able to critically analyse how children acquire new words, explain patterns of error (e.g., overextension of 'doggie' for all four-legged animals), and evaluate the role of innate mechanisms versus environmental input. You'll also understand how vocabulary growth accelerates rapidly after age two, with children learning an average of 10-20 new words per week during the 'vocabulary explosion'.