Technical Abstract: Animals and humans show increased motor and cognitive declines with aging, thought to be due to increased susceptibility to the long-term effects of oxidative stress and inflammation. Previous findings have suggested that improvements in these age-related declines might be accomplished by increasing the dietary intake of polyphenolics found in fruits and vegetables, especially those identified as being high in antioxidant and anti-inflammatory activity. Therefore, we investigated the beneficial effects of two concentrations of Welch's Concord grape juice (10% and 50%) compared to a calorically-matched placebo for their effectiveness in reversing age-related deficits in behavioral and neuronal function in aged Fisher 344 rats. Results showed that rats which drank the 10% grape juice from age 19 to 21 months had improvements in oxotremorine-enhancement of K+-evoked release of dopamine from striatal slices as well as cognitive performance on the Morris water maze, while the 50% grape juice produced improvements in motor function. These findings suggest that, in addition to their known beneficial effects on cancer and heart disease, polyphenolics present in foods may be beneficial in reversing the course of neuronal and behavioral aging, possibly through a multiplicity of direct and indirect effects that can affect a variety of neuronal parameters.