A thesis submitted in partial fulfilment of - Queen Margaret University

sentences. As aphasia also affects the understanding of language it can affect
an individual’s ability to understand complex sentences or impede the ability of a
person to understand even simple sentences or spoken or written single words.
Aphasia can also affect the ability to understand and use various methods of
communication other than speech, for example, gesture (Parr et al., 1997). The
severity of aphasia can also change over time as one area of language may
resolve while others remain impaired. This severity can also fluctuate from one
day to the next where a person may have many word-finding difficulties one day
and on another their speech may be more fluent (Parr et al., 1997). Society
considers the ability to communicate through speech and writing to be signs of
intelligence (Parr et al., 1997). However, while language difficulties that arise as
a result of aphasia may hinder a person understanding or expressing in the
spoken and / or written medium it does not affect their ability to think, feel,
remember and plan, and therefore intelligence is not considered to be affected
by aphasia (Parr et al., 1997).
Aphasia can occur transiently where a person acquires language difficulties, for
example as a result of epilepsy, migraine or transient ischaemic attacks (TIAs),
but this resolves back to their normal baseline or within normal limits in a matter
of hours or days (McNeil and Pratt, 2001). Cerebral tumours can also result in
aphasia (Parr et al., 1997) as can some traumatic brain injury, although this
injury often affects the social uses of language (McDonald, Togher and Code,
1999). The definition of aphasia assumed by this investigation encompasses
acquired language impairment and excludes other communication difficulties
attributable to sensory loss (such as acquired deafness), confusion, dementia,
or speech difficulties due to muscular weakness or dysfunction such as
dysarthria (Darley, 1982). The population participating in this investigation
consisted of people who had acquired language impairment (aphasia) as a
direct result of a stroke. This type of brain injury was chosen for a number of
reasons. CVA is mainly ‘focal’ rather than ‘diffuse’ in nature and from a specific
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