A Psycholinguistic Study on the Pronoun Comprehension and Processing of Turkish Alzheimer’s Patients

Abstract

Many abilities of patients of Alzheimer’s disease (AD) such as attention, language comprehension, processing and production might demonstrate adverse changes as a result of the disease. It has been observed that studies in relation to loss of language abilities in the AD patients mostly focus on the linguistic subfields such as phonology, morphology, syntax, and semantics. These studies are mostly concerned with the language problems of the AD patients, focusing on their production and comprehension. On the other hand, in studies carried out on the AD patients in Turkey, it is revealed that there have been findings in relation to their inabilities in giving responses to questions while following instructions and in responding to the cross-modal naming and the sentence-picture matching tests. However, it is observed that there has not been enough investigation conducted on Turkish-speaking-AD patients regarding their comprehension performances. Therefore, it is thought that the investigation on the linguistic performances of the Turkish-speaking AD patients regarding reflexive, reciprocal and personal pronouns will eliminate the deficiencies in this area to some extent. To this end, the aim of this study was to reveal the comprehension and processing performances of the Turkish-speaking AD patients regarding the aforementioned pronouns through the off-line and on-line tests. In the study, the comprehension and processing of the above mentioned structures by the AD patients were analyzed in relation to the performances of the healthy control subjects. On the other hand, the predictions of the Syntactic Deficit Hypothesis (SDH), the Working Memory Deficit Hypothesis (WMDH) and the Informational Load Hypothesis (ILH) were tested in terms of the comprehension and the processing of the pronouns. In parallel with these aims, twenty mild AD patients were involved in the study as the participants of the experimental group. On the other hand, twenty-two cognitively healthy subjects participated in the control group of the study. All participants were matched in terms of education, age and gender. In accordance with the aims of the study, three tests were employed to the control and experimental subjects to collect the data of the study: 1. The Standardized Mini Mental Examination (SMMSE) test, 2. The Sentence-Picture Matching (SPM) test and 3. The Cross-Modal Naming (CMN) test. The cognitive status of the participants was analyzed by the Standardized Mini Mental Examination test. Following the administration of the SPM test, the comprehension of the reflexive and reciprocal pronouns in relation to their referential dependencies in simple and complex sentences were analyzed. The CMN test, which was the third data collection tool, was employed to gather data on the personal pronoun processing of the participants. The findings of the SMMSE test indicated that there was a statistically significant difference between the mild AD patients and the control group and it was observed that the mild AD patients had cognitive impairments. In addition, the Mann- Whitney U test results of the other two tests demonstrated that there was no statistically significant difference between the groups concerning the performances on the comprehension and processing of the pronouns. However, when the performances of the groups were individually analyzed with the Wilcoxon Signed Rank test, it was observed that there were differences concerning the comprehension and processing performances. In addition, the results of the study supported the predictions of the Working Memory Deficit Hypothesis in terms of the pronoun comprehension and processing of the participants.