EurekAlert -- Before swatting at one of those pesky flies that come out as the days lengthen and the temperature rises, one should probably think twice. A University of Missouri researcher has found, through the study of Drosophila (a type of fruit fly), that by manipulating levels of certain compounds associated with the “circuitry” of the brain, key genes related to memory can be isolated and tested. The results of the study may benefit human patients suffering from Parkinson’s disease and could eventually lead to discoveries in the treatment of depression.