Geneticists in Germany trained mice of different ages to solve a variety of cognitive tests. The oldest mice had the hardest time learning these tasks, and failed to activate genes that are important for memory.
Treating these older mice with a specific molecule that repaired a specific histone modification defect in the mouse DNA resulted in significant improvement in the animals' ability to learn. Of course, this is mouse research, but it is encouraging to know that human age-related memory loss may be reversible in the future.
PositiveTip: We can be thankful for the faithful efforts of scientists to identify why things sometimes go wrong, and then develop new treatments for age-old problems.