Autobiographical memory in Alzheimer's disease: a systematic review

Introduction: Autobiographical memory impairment is a significant feature of Alzheimer’s disease (AD), affecting recall of personal events and the sense of self. Despite extensive study, the literature lacks a comprehensive synthesis of how deficits relate to memory specificity, temporal gradients, and emotional processing. Methods: A systematic review following PRISMA guidelines was conducted across PubMed, Scopus, ScienceDirect, and Web of Science. Studies comparing autobiographical memory performance between AD patients and healthy controls were included. Quality assessment used Yang’s QUADAS-C checklist; two reviewers independently screened titles, abstracts, and full texts against predefined criteria. Results: Across 83 studies, AD patients showed consistent autobiographical memory deficits characterized by reduced specificity and overgeneralization across life periods. A temporal gradient was observed with better preservation of remote over recent memories, supporting Ribot’s law; the reminiscence bump was often preserved. Emotional processing was altered, with reports of positivity bias or emotional neutrality; emotional intensity could be preserved despite reduced specificity. Music and odors were particularly effective cues for retrieval compared to other stimuli. Neural correlates implicated hippocampal, prefrontal, and posterior cortical regions; performance correlated with executive functions. Some elements of self-reference were preserved despite memory impairment. Discussion: Autobiographical memory impairment in AD affects multiple cognitive domains, the sense of self, and quality of life. Patterns of impairment and preservation suggest therapeutic targets, diagnostic markers, and the need for standardized AM assessment protocols and multimodal interventions. Early detection and intervention may serve as markers of disease progression. Systematic Review Registration: PROSPERO CRD42024596837.