Where should research start in solving Alzheimer's? That's a tricky question to answer. What exactly are researchers looking for when trying to solve the Alzheimer’s puzzle? “It depends on the researcher,” says Kevin Hascup, PhD. “Really, the tried and true biomarkers are three — amyloid, tau and neurofilament light chain, or what is known as A/T/N.” A biomarker (molecules in blood, body fluid, and tissue) helps with understanding the changes that occur with age and disease onset. Each of the three A/T/N biomarkers progress in its own way in aging and with dementia. But no matter which