Day-to-day memories depend on the hippocampus

The hippocampus - a structure in the brain - controls the brain's ability to learn and form memories of day-to-day facts.

But research found that the activity in the hippocampus steadily declines with age. The memory of subjects in their 50s and 60s weakened as subjects recalled events that were up to 12 years old but reached a plateau during older remembrances.