Abstract
For the majority of children, lexical acquisition occurs quickly and efficiently. Specifying the
necessary prerequisites to the acquisition of full meaning and the extent of the information
acquired in both single and repeated exposures to establish a lexical representation is an
essential element in understanding the acquisition process. The present research considers
two types of prerequisites: child based factors and contextual factors. Two experiments were
designed to assess the relative influence of these factors on acquisition patterns. In the first
experiment child based factors (vocabulary knowledge, phonological memory, age) and
different linguistic contexts for novel word learning are assessed. One hundred and ninety
two children (3;6 - 4;6) were introduced to two novel words. The children in each condition
were read two illustrated story books containing one unfamiliar word per story. After hearing
the story, children’s word knowledge was assessed on seven different lexical tasks
immediately after the introduction and one week later. Correct responses were coded and an
error analysis was performed to evaluate responses. Linguistic context, the child’s
chronological age and phonological memory differentially influenced performance across
tasks. However, the findings OfExperiment 1 were limited in the following ways: Firstly, the
results about the role of children’s existing vocabulary knowledge still remain inconclusive
since children’s performance across tasks was not found to differ significantly by their
existing vocabulary knowledge. Secondly, Experiment 1 demonstrated children’s word
learning in a single assessment. Thus, they are limited in describing the lexical acquisition
as a process over time.
The second experiment considers a) the child’s baseline vocabulary knowledge, b) the impact
of different sources of information and c) prior lexical knowledge and semantic domain, on
the longitudinal acquisition of the new terms. One hundred and thirty children (5;00 - 6;00)
were randomly allocated to five groups. Each intervention group was introduced to four
target words through a series of controlled linguistic contexts over a period of four weeks.
Immediately after each introduction, children’s word knowledge was investigated on seven
lexical tasks. Examination of the children’s lexical representations took place over three
consecutive periods. Group intervention, the baseline vocabulary and the nature of the target
words differentially influenced performance across tasks. Implications of the results from
both experiments for lexical acquisition processes are discussed.