Produção de narrativas orais no envelhecimento sadio, no comprometimento cognitivo leve e na doença de alzheimer e sua relação com construtos cognitivos e escolaridade

Abstract

In Brazil there is a continuous growth of the elderly population. Due to this fact, there will be a significant number of age-related diseases, among them, Mild Cognitive Impairment (MCI) and Alzheimer's disease (AD). Besides the cognitive components routinely investigated for diagnosis and assessment of MCI and AD, such as memories, attention, and executive functions, a deeper investigation of language may provide valuable data for a complementary diagnosis of the disease, since language is one of the most important cognitive components for the daily functioning of the elderly individuals. However, most of the research published in the area considers language processing only at the word and sentence level, being the number of studies at the discourse level more reduced, especially the ones that investigate narrative production in MCI and AD. There is a lack of studies analyzing low education elderly people with MCI and AD; similarly, there is a lack of studies on the impact of education in this type of processing in healthy aging. Moreover, an incipient number of studies correlate linguistic and neuropsychological tests. Based on the gaps in the area, this research aims at investigating the characteristics of narrative production in AD and MCI, especially regarding discourse type, deficits both in coherence and in the narrative superstructure, as well as the use of communicative strategies in oral production. It also aims at investigating the influence of education on linguistic and cognitive performance of two healthy aging groups. Finally, it aims at verifying whether there is a correlation between the linguistic analysis of the narrative and the neuropsychological tests that measure episodic and working memory, as well as executive functions. Participated in this study 94 aging individuals, divided in four groups: two of them composed by healthy elderly individuals with high and low education, and the other two groups with atypical development (in this case, individuals with MCI and AD and low education). A neuropsychological assessment including working and episodic memory and executive functions, and a linguistic assessment of oral narrative production were developed. The participants were required to narrate a story based on a set of seven pictures. Concerning the neuropsychological assessment findings, the MCI and AD groups showed impairment in episodic memory, working memory and executive functions, when compared to the control group. A difference between the MCI and AD groups was found only in episodic memory. With regard to language assessment results, the MCI and AD groups differed from the control group in all analyses proposed, but no differences between the two clinical groups were found. Elderly people with high education had significantly higher scores than the comparative group with low education in working memory, executive functions and in the linguistic assessment. The correlation analysis showed a significant relationship between the performance of the groups in the neuropsychological tests and linguistic assessment. The results of this research are discussed in the light of the hypotheses from the confrontation with the literature. This research may contribute to enlarge Brazilian data in order to better characterize oral narratives characteristics and deficits in a population of healthy aged, MCI and DA individuals. Moreover, it may contribute to aid the complementary diagnosis of MCI and AD, as well as to the desing of cognitive training programs, and cognitive therapy for healthy elderly individuals and the ones with brain injury.