More than 5 million Americans have Alzheimer’s disease, and that number is expected to reach 13.5 million by 2050, according to the Alzheimer’s Association. As America’s population shifts toward an older society, the hope is that earlier detection can lead to earlier intervention to slow or arrest the disease. Now the FDA has approved a tool that offers hope in that direction. The Cognivue, the brainchild of Charles J. Duffy, a neuroscientist from the University of Rochester, is designed to help physicians easily and conveniently detect early signs of Alzheimer’s disease and other forms of dementia. The Washington Post’s Frederick Kunkle reports.