New Software Could Improve Alzheimer’s Screening Methods, Research Finds

Using a digitized pen to complete a traditional cognitive impairment test could give doctors more accurate screening tools.

For years, a common screening method for cognitive impairments—like those that come as a result of Alzheimer’s—has been a simple test called the Clock Drawing Test (CDT), which asks patients to draw a clock showing a specific time, then copy an already-drawn clock. Studying the mental processes that go into completing the CDT helps doctors determine whether a patient shows signs of cognitive decline.

Thanks to a team of researchers, that test is getting a high-tech update. For almost a decade, Randall Davis, of MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL), and Dana Penney, of Lahey Hospital and Medical Center, have been giving the CDT using a specialized digital pen. “What the pen does is capture the writing with considerable temporal and spatial accuracy,” Davis explains. “It measures its position 80 times a second quite accurately on the page.”

Now, the duo, along with researchers from five other institutions, have compiled a paper showing just how much better the digital test (dCTD) is at predicting cognitive impairment than the old technique. “We were able to show that our system performed considerably better than the existing technology that’s out there, even when that existing technology is embodied in code, and therefore is done absolutely the same way every time, rigorously, without getting tired or anything else,” Davis says, adding that, due to human error, scoring isn’t usually done perfectly, anyway.

Better screening methods are crucial, Davis says, because the current system often waits until cognitive function is clearly damaged—by which time a disease has progressed substantially—to start testing. “Imagine if you had to have a heart attack before anyone decided to see what kind of condition your heart is in; that’s a little bit the way things are in the cognitive testing world,” he says. “We want to change that.”

The best news, the couple says, is the dCTD applies not just to Alzheimer’s, but also to diseases such as Parkinson’s, MS, brain injury, and more. “[We want to] elevate cognitive screening to a primary care doctor’s office, along with when they listen to your heart with a stethoscope,” Penney says.