Turning a decade older, Dr. Daryl Appleton is tackling this week's F-word: 40. But don't worry, this isn't a birthday listicle episode.
She traces the psychology of midlife from its 1965 origin (a study of 300 artists) through the famous U-shaped happiness curve, replicated across 145 countries and hundreds of papers, to the twist: recent research shows that U-shape has disappeared. Unhappiness now peaks at 18 to 24, especially among young women. Using Stanford's socioemotional selectivity theory and decades of MIDUS data, Dr. Daryl argues the real driver was never your age. It's the gap between where you are and a deadline you never consciously agreed to.
She wraps with four practical exercises, including a deadline inventory and a time-horizon test, to help you figure out whose timeline you've actually been living by.
The number isn't the problem. The deadline you've attached to it is.