Two new papers by a team of researchers demonstrate that evaluating microRNAs in blood can be used not only to diagnose mild cognitive impairment (MCI) but also, critically, to predict the conversion from MCI to dementia due to Alzheimer's disease. Moreover, the researchers uncovered microRNA candidate molecular biomarkers that associate with current Amyloid, Tau, and Neurodegeneration (A/T/N) Alzheimer's biomarkers.