Natural compounds found in apples and other fruits may help to stimulate the production of new brain cells, which could have implications for learning and memory, according to a new study by researchers at the University of Queensland, and the German Center for Neurodegenerative Diseases. The results of their work in cultured cells and in mice indicated that quercetin, together with other compounds found in apples, may act in synergy to promote neurogenesis and possibly aid brain function, when given in high concentrations.