The most general preclinical sign of Alzheimer’s is known to be depression, so a team at Brigham and Women’s Hospital set out to explore the relationship between the build-up of amyloid beta in the brain and specific symptoms of depression.  The study followed 270 cognitively healthy senior citizens aged between 62 and 90 years old. Over a span of five years these subjects underwent positron emission tomography (PET) scans to measure cortical levels of amyloid beta.  The results clearly pointed to a correlation between increasing anxious-depressive symptoms and higher levels of amyloid beta in the brain. {read more here}