A thesis submitted in partial fulfilment of - Queen Margaret University

esearchers (Breedin et al., 1998; Warburton et al., 1996; Daniele et al., 1994;
Caramazza and Hillis, 1991). Dissociations have also been observed between
proper nouns and common nouns (Robson et al., 2004) with common nouns
being seen as having more semantic depth (Schmidt et al., 2004; Lyons et al.,
2002; Miceli et al., 2000; Yasuda et al., 2000). Therefore in order to avoid
difficulties arising in data interpretation due to word class, this investigation will
select only one word class for its stimuli. Nouns by their very nature are more
concrete and imageable than verbs therefore nouns will be used for this
investigation. As learning new words involves making associations with already
known vocabulary, it was thought that words with more semantic depth would
facilitate this learning. Thus common nouns were chosen over proper nouns
which are thought to lack this depth. The word class of the new vocabulary
stimuli for the main investigation will therefore include common nouns only. The
stimuli will be discussed later in section 2.9.1.
2.8.5 Current evidence for learning new vocabulary
Howard (1999) states that the course of recovery of aphasia cannot be equated
with language acquisition; however as there is no current theory of aphasia
rehabilitation it is not known if the processes used in language acquisition are
utilised in aphasia therapy. It is therefore essential to investigate the ability of
adults (both with and without cortical damage) to learn new vocabulary. The
studies discussed below involve the demonstration of vocabulary learning by
healthy adults with no history of brain damage, people with memory impairment
and also people with post-stroke aphasia.
2.8.5.1 Healthy adults learning vocabulary
There have been a small number of studies evaluating various learning
techniques for adults acquiring new vocabulary. Some of these investigations
employed learning unfamiliar words. Others observed the learning of a foreign
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