A thesis submitted in partial fulfilment of - Queen Margaret University

Abstract
Recent studies have established that adults with post-stroke aphasia can learn
to establish connections between familiar words and abstract images, and nonwords
with familiar objects. What has not been investigated was whether adults
with aphasia could learn non-words with abstract images/ novel meanings i.e.
new vocabulary. The main objective of this study was to investigate whether
adults with post-stroke aphasia could learn ‘novel’ word forms with ‘novel’ word
meanings, despite phonological and/or semantic impairment. Specific research
questions included: Can post-stroke adults with aphasia learn new vocabulary?
If so, what factors affect their capacity to learn? Is it possible to predict which
individuals will learn most successfully? The methodology was developed using
preliminary studies both with adults of normal language and cognitive
functioning and post-stroke non-aphasic and aphasic adults. It incorporated
learning theory and a cognitive neuropsychological model of language. A range
of assessments was used to facilitate the capture of new learning. ‘New
learning’ was measured not only in terms of the accurate production of the new
stimuli but also the recognition and knowledge of the word forms and meanings
of this new vocabulary. In the main investigation twenty novel word forms with
20 novel meanings were taught to 12 aphasic adults (< 65 years), over a fourday
period, using an errorless learning paradigm. Immediate recall of these
newly learnt representations was investigated as well as delayed recall.
Quantitative and qualitative results from a case series of 12 participants are
presented and discussed. Despite semantic and phonological difficulties, all but
three participants demonstrated substantial learning of the new vocabulary. The
participants’ range of learning ability (from both immediate and delayed recall
data) was analysed in relation to severity of aphasia, cognitive factors (including
attention, memory and executive function), as well as variables such as age,
months post-stroke and number of years in education. With an intensive training
period, these participants with aphasia demonstrate varying degrees of ability for
new learning. Possible influencing factors and implications for speech and
language therapy rehabilitation are discussed.