Hippocampal size and memory function in the ninth and tenth decades of life: the Sydney Older Persons Study
- 1Centre for Education and Research on Ageing, Concord Hospital, Sydney, Australia
- 2Prince of Wales Medical Research Institute and the University of New South Wales, Sydney, Australia
- 3School of Psychology, the University of Sydney, Sydney, Australia
- 4Department of Radiology, Concord Hospital, Sydney, Australia
- 5Prince of Wales Hospital, Randwick, Sydney, Australia
- Correspondence to: Dr T Lye Centre for Education and Research on Ageing, Concord Hospital C25, Concord NSW 2139, Australia;
- Received 5 January 2003
- Accepted 9 September 2003
- Revised 25 August 2003
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.
- CDR, Clinical Dementia Rating
- CES-D, Centre for Epidemiological Studies Depression scale
- CVLT, California Verbal Learning Test
- MRI, magnetic resonance imaging
Competing interests: none declared