Asymmetries of brain glucose metabolism and memory in the healthy elderly

The relation of discrepancies between visual and verbal memory to right-left asymmetries of resting state brain glucose metabolism was studied in 11 healthy elderly subjects. Short- and long-term memory were measured with experimental continuous recognition tests. Regional cerebral metabolic rates for glucose were determined with positron emission tomography (PET) using 18F-fluoro-2-deoxy-D-glucose. Long-term memory discrepancy was related to parietal and hemispheric metabolic asymmetries, such that subjects with better visual than verbal memory had higher right than left brain glucose metabolic rates, whereas others showed the opposite pattern. These results show that specific visual and verbal memory abilities in the healthy elderly are related to regional differences in cerebral cortical metabolism.