Now, researchers funded by the Agricultural Research Service (ARS) have added compelling new research findings to earlier reports showing, in rat studies, that compounds in blueberries had reversed existing short-term memory losses.

The findings were presented in a poster by Gemma Casadesus, a graduate research associate working with James A. Joseph, head of the Neuroscience Laboratory of the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston. The poster was presented in November at the Society for Neuroscience's annual conference.

The researchers found an increased birth rate of brain cells in the hippocampus — a brain region responsible for memory — in aged rats fed blueberry supplementation equal to one cup daily in humans for two months, when compared to non-supplemented rats.

The hippocampus is one of the few areas in the brain that continuously replaces neurons through a process called neurogenesis, a term that encompasses proliferation, survival and differentiation of precursor cells.

Moreover, these changes were associated with improved memory performance in the blueberry-supplemented rats. The scientists will follow by studying the interaction of blueberry compounds with the molecular mechanisms responsible for the modulation of neurogenesis.

In tandem with these findings, ARS Plant Physiologist Freddi A. Hammerschlag and ARS Plant Geneticist Lisa J. Rowland have been working to develop blueberry cultivars endowed with cold tolerance. Such hardiness is ultimately hoped to boost U.S. blueberry growers' current 350-million-pound annual output.

The two plant scientists, who are with the ARS Fruit Laboratory in Beltsville, Md., recently worked out a system to regenerate blueberry plants from tissue taken from the commercially important cultivar, Bluecrop. Regeneration is a laboratory technique used to produce whole plants from single cells that have been pegged as genetically attractive.

ARS is the USDA's chief scientific research agency.