Our brain is a treasure trove of memories that form as billions of tiny electrical signals fire off between nerve cells (neurons). Everyday experiences create patterns of signals that vary in type and strength. But, with the onset of Alzheimer’s disease these patterns are disrupted so that treasured memories disappear and new ones are not easily stored. The decline is triggered when two proteins in the brain, called tau and beta amyloid, clump together, and brain cells called astrocytes (here dyed red) accumulate. These tangles multiply, killing vital neurons (shown in blue) as they spread. Scientists have discovered that it’s a highly toxic version of beta-amyloid (shown in green) that ignites this cascade, and escalates spread of disease through the brain. The race is now on to find medicines that can extinguish this spark and protect more memories.
Written by Caroline Cross
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences (the new name for the MRC Clinical Sciences Centre) the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.