Hippocampal size and memory function in the ninth and tenth decades of life: the Sydney Older Persons Study

Abstract

Objectives: The purpose of this study was to define magnetic resonance imaging (MRI) correlates of normal brain ageing, with the specific objective of investigating whether the size of the hippocampus is selectively correlated with age related memory performance in non-demented individuals in their ninth and tenth decades of life. Methods: Hippocampal size was estimated using MRI based volumetry and qualitative visual assessment in 102 community dwelling individuals aged between 81 and 94 years. Participants were evaluated on a variety of clinical and experimental instruments, including a comprehensive neuropsychological test battery. All participants underwent neurological examination, an extensive medical history was obtained, and an informant confirmed details of each participant's functional ability. Results: Both visual and volumetric hippocampal measures were identified as robust predictors of memory performance, even when the influence of age related illnesses and sociodemographic variables was accounted for. When the sample was reduced to include the most cognitively healthy participants who were rated by an informant as showing no evidence of cognitive decline, the left hippocampal measures remained significant predictors of delayed retention of verbal material. Conclusions: These findings suggest that hippocampal volumes are selectively correlated with memory functioning in both normal and successful ageing.

Prevalence of Sensory and Cognitive Disabilities and Falls, and Their Relationships: A Community-Based Study

“…Concerning cognitive disabilities, our study shows that their prevalence increases with age, markedly so after 70 years, for concentration-attention, orientation, problem-solving, and memory. The alterations in cognitive function in the elderly can be caused by atrophy in certain cortical areas [35] or the hippocampus [36] and by modifi cation in neural plasticity [37] .…”

Differential Cross-Sectional and Longitudinal Impact of APOE Genotype on Hippocampal Volumes in Nondemented Older Adults

“…Several studies have reported larger hippocampal volumes are associated with better memory performance [16][17][18][19] , though not all investigations have found this relationship [20] . Several studies, in fact, have found hippocampal volumes to be related to memory performance in cognitively impaired samples, but not in cognitively healthy participants [21][22][23] or more mildly impaired individuals, such as in age-associated memory impairment [24] .…”

Visual rating of the hippocampus in non‐demented elders: Does it measure hippocampal atrophy or other indices of brain atrophy? The SMART‐MR study

“…Although hippocampal atrophy assessed with visual rating scales in diagnostic and prognostic studies have proven to differentiate between patients with Alzheimer's disease and healthy controls (Scheltens et al, 1992;Wahlund et al, 2000;Bresciani et al, 2005)and other studies reported that rating scales predict memory performance in normal aging and in subjects with mild cognitive impairment (Korf et al, 2004;Lye et al, 2004;van de Pol et al, 2007), it is likely that measures of global or subcortical atrophy perform equally well. Also, volumetric measurements of the hippocampus may be the preferred method over rating scales if the objective is to examine whether hippocampal volume loss is disproportionate relative to other brain tissue loss, since this is generally considered to be the case in early stages of Alzheimer's disease (Laakso et al, 1997).…”

“…The visual rating scales have demonstrated to correctly classify healthy controls and demented patients (Scheltens et al, 1992). Qualitative rating also has proven to be as sensitive as volumetric measurements in predicting memory performance in normal aging, suggesting that it may be a diagnostic tool for early detection of Alzheimer's disease in clinical practice (Lye et al, 2004). However, the correlation between the visual rating scores and the volume of the hippocampus described in previous reports is only moderate with a correlation coefficient between 0.27 and 0.42 (Wahlund et al, 1999;Visser et al, 2002).…”