A thesis submitted in partial fulfilment of - Queen Margaret University

information about a word (Harley, 2001). Each word that is learned is thought to
contain a number of levels of information such as the word form (the
combination of sounds – phonology, and letters used for spelling – orthography);
the conceptual meaning(s) of each word and its associations to other known
words (semantics) and the grammatical behaviour of each word (nouns, verbs
and role of the word in a sentence) (Nation, 1995). The basic representations of
vocabulary will now be briefly described.
2.8.1 Word form
The representation of the word forms of vocabulary consists of the combination
of individual sounds which divide into rhythmical units forming syllables. The
word forms consist of the acoustic form of speech sounds (auditory) and how
they are articulated (spoken) (Harley, 2001). It was previously suggested that a
word’s phonemes were stored separately and each time the word was spoken it
had to be reformed sound-by-sound (Becker, MacAndrew and Fiez, 1999).
However current evidence suggests that it is more likely that the phonological
shape of a word, familiar through repetitive use, would be stored in for example
syllable form and does not need to be reconstructed each time the word is
produced (Levelt, Roelofs and Meyer, 1999). There has been much discussion
regarding whether there is one lexicon that facilitates the access of four
modalities – listening, speaking, reading and writing, when retrieving a word or
whether there are four discrete lexicons, one for each modality. Evidence from
error analysis in cognitive neuropsychology indicates that the mental lexicon is
fractionated with a separate lexicon for each modality (see Ellis and Young,
1996; Kay et al., 1992). The production of words is considered to be a staged
process beginning with the concept or idea to the retrieval of the word’s
phonological shape from the lexicon (Levelt et al., 1999). In normal speech we
recall two to three words per second from our lexicon that is thought to contain
many thousands of words (Levelt et al., 1999). Word form errors are produced
by healthy individuals (slip-of-the-tongue phenomena) occurring in just one per
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