Another problem: as many as 30 percent of people enrolled in Alzheimer's studies based on symptoms didn't actually have the disease -- they had other forms of dementia or even other medical conditions. That doesn't give an accurate picture of whether a potential treatment might help, and the new definition aims to improve patient selection by using brain scans and other tests.

Out of the total number, 48 were scans of people with the disease, while 48 were scans of people who suffered from mild cognitive impairment and eventually developed full-blown Alzheimer's. The AI was able to diagnose Alzheimer's 86 percent of the time. More importantly, it was able to detect mild cognitive impairment 84 percent of the time, making it a potentially effective tool for early diagnosis. With more samples and further development, though, the AI could become more accurate until it's reliable enough to be used as a non-invasive early detection system.

Roberts said in a statement Tuesday that although O'Connor has announced she is withdrawing from public life, "no illness or condition can take away the inspiration she provides for those who will follow the many paths she has blazed."

Alzheimer's disease is explored in Lembit Beecher's'Sky on Swings,' starring 73-year-old mezzo-soprano Frederica von Stade and commissioned by Opera Philadelphia for the first night of its season-opening O18 festival.

My brain did it again. I had completed 7 months of a grueling treatment for a neurological disorder that had plagued me for several years. I just had these 20-second episodes where I couldn't read or write, and sometimes it made it hard for me to speak. After finishing the treatment and making some changes to my medication, the episodes nearly stopped. I would occasionally experience light symptoms, which shouldn't have mattered.