The researchers in this study tested F.A for various other impairments which, according to previous ideas and theorists of speech systems, may have been affected during the stroke. Speech perception was tested at a phonological level and a semantic level, both of which F.A scored highly in which excluded the idea of problems with language comprehension. In regards to speech production, F.A showed only slight impairments in word production and word repetition, and dramatic impairments in pseudo word repetition. A more detailed analysis of the error types showed that when reading, F.A makes phonemic errors only and performs well on speech perception tasks.
From this information, we can learn that in a person who has not experienced any brain injury, separate phonological input and output codes are used in a modality specific way by the phonological systems and related conversion mechanisms, therefore enabling pseudo word repetition. Also, F.A`s performance of particular tasks, such as the rhyme judgment task which is designed to observe whether or not the conversion mechanism between the phonological input and output systems is functioning or impaired, showed that impairments were only visible when converting phonological input codes into output codes and not vice-versa which suggests that in the result of brain injury, one can be selectively spared.
Overall this study provides a good framework for understanding the impairments resulting from conduction aphasia although the study needs to be repeated on a larger sample as one aphasic patient is not enough to be able to generalize the results even when compared to a large control group. This causes one to question the reliability and validity of the research in question (Eisenhardt 1989). The study also assumes support from an anatomical level as research into this area, such as that by Matsumoto et al (2004) suggests a two-way connection between the Brocas and Wernickes areas via the accurate fasciculus which is assumed to be the coordinator of data between these two areas. Although this assumption is made, the CT scan received by F.A at admission is not detailed enough to show the accurate fasciculus so it is unknown as to whether or not the lesion crosses its path. The layout of this report is not particularly straight forward and rather un-organized as the methods section is not clearly defined and the hypothesis is not explicitly or implicitly stated until the discussion. On the other hand if the study is replicated and more similar findings are found, this study could prove to be a milestone for the people who care for and manage the symptoms of conduction aphasic patients.
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