Ties between lexical and grammatical development: evidence from early-talkers

Area of Science:

• Developmental Psychology
• Linguistics
• Cognitive Science

Background:

• Early language development is crucial for cognitive and social skills.
• Understanding variations in early language acquisition, such as differences in vocabulary size and utterance length, is essential.
• The relationship between semantic and grammatical development in young children requires further investigation.

Purpose of the Study:

• To investigate a case study of two early-talkers exhibiting a dissociation between vocabulary size and mean length of utterance.
• To determine if this dissociation is best explained by a grammar-semantics divide or by cognitive style differences.
• To propose a unifying account for observed variations in early language development.

Main Methods:

• Case study analysis of two children (aged 1;9 and 1;5) identified as early-talkers.
• Comparison of early-talkers to age-matched control groups (10 in Early Stage I, mean age 1;7; 10 in Stage II, mean age 2;3).
• Exploration of linguistic data to assess grammar, semantics, and cognitive processing styles.

Main Results:

• The child with a large vocabulary but short utterances showed high proportions of predicates and grammatical morphemes, indicating no grammar-semantics dissociation.
• Clear distinctions between analytic and holistic cognitive processing styles were not supported.
• Partial support was found for cognitive style predictions, suggesting nuances in processing differences.

Conclusions:

• The findings do not support a dissociation between grammar and semantics in early language development.
• Observed differences in early language acquisition may be better explained by variations in auditory short-term memory capacity.
• Auditory short-term memory could influence the linguistic units children can process and retrieve during development.