Explanation:
Focusing on the frontal lobe and hippocampus, the most shrink-prone regions of the human brain, the researchers found the expected loss of brain size with age in the human volunteers. But the chimps' brains showed no size change at all. Long lives, shrinking brains.
Brain mass: Shrinkage in the frontal lobe and hippocampus – areas involved in higher cognitive function and encoding new memories – starting around the age of 60 or 70 years.
