A thesis submitted in partial fulfilment of - Queen Margaret University

of new vocabulary where both the word form and word meaning was novel. A
number of the studies employed already held phonological representations, for
example, use of surnames (Downes et al., 1997), dog breed names (Marshall et
al. 2001; Freed et al., 1998) or familiar words (Freed et al., 1995; Marshall et al.
1992; Grossman and Carey, 1987). Other studies used novel word forms (nonwords)
with already held semantic representations – pictures of familiar objects
(Basso et al., 2001; Lotto and de Groot, 1998; Van Hell and Mahn, 1997).
Therefore, the question of whether the damaged adult linguistic system is
capable of acquiring new vocabulary involving new word forms and word
meaning/concepts still remains to be investigated. As previously discussed (see
section 2.7), the actual mechanism underlying the improvement of language
disorders is largely unknown. Speculation includes the possibility that the person
is accessing inhibited memory traces that require re-exposure to the ‘forgotten’
items for reinstatement (Bjork and Bjork, 1996). However, another alternative
hypothesis is that new learning is taking place during the rehabilitation process.
Current knowledge of therapeutic intervention does not differentiate between
therapy that reactivates existing representations or processes and therapy that
leads to the acquisition of new representations and processes. Knowledge about
whether the damaged linguistic system is able to acquire new information will
also inform any theory of rehabilitation and that of related brain plasticity and
cortical reorganisation. Therefore, this investigation aims to address this
question and evaluate whether people with aphasia can demonstrate the
learning of new vocabulary (i.e. new word forms with new meanings) despite
having language impairment. As this study is pioneering in the field of aphasia
rehabilitation the methodology had to be created. In order to do this a number of
issues were addressed and are discussed below.
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