both experiments, a series of multiple measures of lexical knowledge was developed and
used.
The analysis of the two experiments, which was both quantitative and qualitative,
demonstrated that different parameters take part in lexical acquisition. These were identified
as the child based factors such as: child’s age, phonological memory, prior vocabulary
knowledge; the nature of the lexicon such as: semantic domain and prior knowledge of the
target words and the nature of the input, such as linguistic context. Issues on measuring word
knowledge as well as the discrepancy between comprehension and production were also
raised.
8.3 Parameters contributing to Lexical acquisition
8.3.1 Child based factors
The child based factors shown as playing a key role in lexical acquisition from context were
children’s age, their phonological memory, their existing vocabulary (receptive) knowledge
and prior lexical knowledge (receptive and expressive) as well as their prior knowledge of
the lexical items. The main patterns identified are discussed in the following subsections.
8.3.1.1 Children perform better in the lexical tasks as they get older
Age was found to be an important factor for lexical acquisition. Experiment 1 demonstrated
that the older age group children performed better across tasks than their younger age
counterparts. The pattern was still the same, even when age was covaried for vocabulary and
memory scores. Unfortunately, little empirical information is available regarding different
processes used at differing age levels, because very few studies span even two age groups.
Nevertheless, age related differences in word learning have been documented by Crais
(1987) as well as by Heibeck and Markman (1987). However, both studies included different
age groups from the present study.
Nelson (1988) claims that distinct problems are encountered within each period therefore,
differing processes of acquisition should be expected at each developmental level. These
developmental differences may be due to different factors. It is probable, that the older
children have more experience with the world which helps them organise better and acquire