Dr. Gregory Harshfield and Martha Castles (IMAGE) Medical College of Georgia at Augusta University Caption Dr. Gregory Harshfield, director of the Medical College of Georgia's Georgia Prevention Institute, and Martha Castles, research manager. Credit Medical College of Georgia Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.