A Longitudinal Study of Episodic and Semantic Autobiographical Memory in aMCI and Alzheimer’s Disease Patients

Abstract

Background: The main objective of this study was to analyze the evolution of autobiographical memory (both episodic and semantic) in patients with mild cognitive impairment, patients with Alzheimer’s disease, and a healthy control group. We compared these groups at two time points: first, at baseline, and in a follow-up after 18 months. Method: Twenty-six healthy older adults, 17 patients with mild amnestic cognitive impairment, and 16 patients with Alzheimer’s disease, matched on age and educational level, were evaluated at both time points with the Autobiographical Memory Interview. Results: The results showed significant longitudinal deterioration in episodic and semantic autobiographical memory in patients with mild cognitive impairment and in patients with Alzheimer’s disease, but not in healthy older adults. Conclusions: The deterioration of episodic and semantic autobiographical memory in AD is confirmed; however, although the episodic was impaired in aMCI, a pattern that evolved toward deterioration over a period of eighteen months was observed for the semantic autobiographical memory.

Episodic and Semantic Autobiographical Memory in Mild Cognitive Impairment (MCI): A Systematic Review

“…Fourteen studies out of twenty-one have studied this aspect, while seven articles [26,32,[34][35][36][37][38] focused only on the episodic component. Among the 14 articles that analyzed autobiographical semantic memory, 4 of them [21,24,29,33] have not found any significant differences in semantic memory scores between patients with MCI and healthy controls. On the other hand, seven studies [22,23,25,28,30,31,39] have found a worse semantic performance in patients with MCI when compared to the HC group.…”

“…Attrition and reporting biases posed low risks in all of the included studies. Instead, sample bias risk was high in six articles [15,[29][30][31][32][33], due to the lack of demographic information (e.g., female ratio, mean age, mean years of schooling). Moreover, measurement bias risk was high in eight studies due to the use of non-validated or ad hoc tasks to measure autobiographical memory.…”

“…The mean years of schooling varied from 7.6 (SD = 2.6) to 16.68 (SD = 3.96) in the MCI group and from 7.9 (SD = 2.5) to 16.06 (SD = 2.80). Five articles did not report years of education [29][30][31][32][33]. Moreover, all the studies have been conducted in Europe, except for six articles that have been placed either in Canada [16,21,27,36] or in Australia [29,30].…”