The richest people in the world are putting some of their fortunes toward finding a better way to diagnose Alzheimer’s disease.

Bill Gates and Jeff and MacKenzie Bezos are backing the Diagnostics Accelerator, a fund that supports researchers looking for earlier ways to detect, and eventually prevent, Alzheimer’s.

Last summer, the Alzheimer’s Drug Discovery Foundation launched the fund with initial commitments of $35 million from several leaders in business and medicine, including Bill Gates. Today, the organization announced it has raised about $15 million in new funding from existing donors and the Bezos family.

Gates summarized the challenges in current Alzheimer’s diagnostics and opportunities to improve in a blog post published Tuesday. According to Gates, the best current methods for diagnosing Alzheimer’s, a spinal tap or brain scan, leave a lot to be desired because they’re costly and invasive.

“What does the ideal Alzheimer’s diagnostic look like? It needs to be cheap and easy to administer,” Gates wrote. “It should tell us not only whether you have Alzheimer’s, but how far advanced the disease is.”

He noted that scientists are close to nailing down a blood test for Alzheimer’s but he’s interested in taking diagnostics even further. Gates believes a digital test for the disease may be in our future.

In the blog post, he highlighted the work of Dr. Rhoda Au, a researcher running a project called the Framingham Heart Study, which has been tracking the health of one community for 70 years. Au has thousands of audio files of patients, some of whom have developed Alzheimer’s. She’s exploring whether technology can be used to analyze voices for early signs of Alzheimer’s.

What if we could use digital technology, not medicine, to identify individuals years before they start to develop mental decline?

“What if we could find an even less invasive way to diagnose Alzheimer’s?” Gates wrote. “What if we could use digital technology, not medicine, to identify individuals years before they start to develop mental decline?”

The Diagnostics Accelerator commitment is the first donation Jeff and MacKenzie Bezos have publicized since announcing plans to divorce in January. At the time, the couple said they would remain “partners in ventures and projects.”

“I am grateful to be joined in this effort by my friends Jeff and MacKenzie Bezos,” Gates wrote Tuesday in his blog post. “They have been tremendous partners who are deeply committed to finding an end to this disease.”