The study of lexical relations device in speech of elderly Alzheimer patients and non-patients

Verbal cohesion is one of the comprehension factors that can be affected by Alzheimer. Lexical relations device is also one of cohesive devices. Despite substantial researches in the field of neurological diseases and cohesive devices, there has been no analysis and comparison of lexical relations as a subset of cohesive devices in the speech of elderly Alzheimer patients and non-patients yet. Therefore, it seems necessary to perform such studies. Besides, the study of possible disorders in the speech of elderly Alzheimer patients is a step toward a more accurate illustration of brain and language relation and may contribute to verbal rehabilitation of these patients as well. The purpose of this research was to study and compare the application of lexical relations device in the speech of elderly Alzheimer patients and non-patients based on Dooley and Levinson’s (2001) perspective. The participants of this research were 6 elderly Alzheimer and 6 elderly non-patients who lived in nursing homes of Birjand and Qaen. The linguistic data was gathered during 5 months (22 September 2012 to18 February 2013). The age range of the subjects was 74 to 90 years old, who were all women with severe Alzheimer. A 40 minute speech sample of each subject was recorded. The data was analyzed using SPSS software version 20 and independent t test. The results of t-test analysis indicated that there was a significant difference between the application of lexical relations device in the speech of non-patients and elderly Alzheimer patients (P=0.009). In fact, based on individual results of all kinds of lexical relations, it was observed that, except for collocation device (P=0.107), there was a significant difference in the other two subsets: part-whole (P=0.019) and hyponymy (P=0.044). It seems that there was a significant difference between the application of lexical relations device in the speech of non-patients and elderly Alzheimer patients.