Evolution of autobiographical memory impairments in Alzheimer's disease and frontotemporal dementia – A longitudinal neuroimaging study. (February 2018)

• Record Type: Journal Article
• Authors: Irish, Muireann; Landin-Romero, Ramon; Mothakunnel, Annu; Ramanan, Siddharth; Hsieh, Sharpley; Hodges, John R.; Piguet, Olivier
• Is Part Of: Neuropsychologia. Volume 110(2018)
• Page Start: 14
• Page End: 25
• Publication Date: 2018-02
• Subjects: Episodic memory -- Semantic memory -- Posterior cingulate cortex -- Lateral temporal cortex -- Neuroimaging -- Consolidation; Neuropsychology -- Periodicals; Neurology -- Periodicals; Psychophysiology -- Periodicals; Neuropsychologie -- Périodiques; Neuropsychology; Periodicals; Electronic journals; 616.8
• DOI: 10.1016/j.neuropsychologia.2017.03.014
• Languages: English
• ISSNs: 0028-3932

Abstract

Abstract: Compromised autobiographical memory (ABM) retrieval is well established in dementia, attributable to degeneration of a core memory brain network. It remains unclear, however, how the progressive spread of atrophy with advancing disease severity impacts ABM retrieval across life epochs. To this end, we conducted a longitudinal study of recent and remote ABM in Alzheimer's disease (AD, n =11), and a frontotemporal lobar degeneration group (FTD, n =13) comprising 7 behavioral variant FTD and 6 semantic dementia patients, in comparison with 23 healthy older Controls. Patients were re-assessed approximately one year following their initial visit and underwent repeat testing and brain imaging. Linear mixed modeling neuroimaging analyses explored disease-specific cortical changes driving ABM alterations over time. AD patients showed comparable ABM profiles across assessment periods however, follow-up performance correlated strongly with lateral temporal lobe integrity. In contrast, recent ABMs were disproportionately disrupted at follow-up relative to baseline in the FTD group, attributable to cortical thinning in posterior brain regions, including the right posterior cingulate cortex. Our findings offer new insights regarding the potential time-specific role of discrete cortical regions in ABM retrieval and the differential fate of formerly evocative memories with advancing disease severity in dementia syndromes. Highlights: Autobiographical memory was assessed longitudinally in AD and FTD. AD patients showed comparable memory performance across time periods. Recent memory was most vulnerable to decline in FTD at follow-up. Neuroimaging analyses revealed time-specific roles for discrete cortical regions. Posterior parietal regions appear crucial for recent autobiographical memory.