Furthermore, qualitative analysis of the association task, demonstrated that children provided
more semantic and perceptual justifications over time, while in the story generation task, they
provided more functional and semantic properties over time. It is probable that children’s
exposure to informative linguistic contexts guided their attention to the semantic and
perceptual properties of the words’ meanings. Lastly, in the naming task the children made
fewer overextension errors over time.
The obtained results from Experiment 1 demonstrated how limited our understanding for
lexical acquisition can be, if we base our inferences only on one assessment. Additionally,
Experiment 2 demonstrated that children’s representations (both of the phonological and
semantic properties) of the novel words change over time moving towards the establishment
of a correct representation of the word’s meaning.
Change of lexical representations over time has been supported by the Representational
redescription model by Karmiloff-Smith (1995). According to the model implicit information
becomes explicit knowledge to the mind through representational redescription. However,
the model cannot account for the group differences in the analogy task for example during
Experiment 1 (see in following section) since it does not take into account the environment.
8.5 Towards a model explaining Lexical acquisition from context
Taking together the results from both experiments it can be concluded that a model of lexical
acquisition is required that takes into account different factors and draws on different
theoretical positions. The factors identified from the present research are: (a) child based
factors (age, existing vocabulary∕prior lexical knowledge, phonological memory and prior
knowledge of the lexical items); (b) the nature of the lexicon (semantic domain of the novel
words) and (c ) the nature of the input (linguistic context).
It is proposed that a model of lexical acquisition could draw on explanations proposed by
three different theoretical positions such as the Interactive functional model and the theory
oflexical acquisition in discourse context proposed by Nelson (1990) in relation to theories
of learning from context (Stemberg and Powell, 1983).