The doctor who developed a widely used test that screens for early signs of dementia and Alzheimer’s disease says that cognition is “a pertinent question” during a presidential election with presumptive candidates over age 70. Problem is, both sides of the political divide are interpreting this test incorrectly. Dr. Ziad Nasreddine in 1996 developed and copyrighted the Montreal Cognitive Assessment (MoCA) test, which is a 10-minute examination usually performed with pen and paper that measures the strengths of different areas of the brain related to cognitive domains, such as short-term memory, spatial awareness and executive functioning. (Remote testing, including via...