Midlife crisis apparently is a myth.

• Position: Aging

While even the best wines eventually peak and turn to vinegar, a study by researchers at the University of California, San Diego, suggests a paradoxical trend in the mental health of aging adults: they consistently seem to get better over time. "Their improved sense of psychological well-being was linear and substantial," says senior author Dilip Jeste, Distinguished Professor of Psychiatry and Neurosciences and director of the Center on Healthy Aging. "Participants reported that they felt better about themselves and their lives year upon year, decade after decade."

Conversely, Jeste and colleagues note high levels of perceived stress and symptoms of depression and anxiety among adults in their 20s and 30s participating in the study. "This 'fountain of youth' period is associated with far worse levels of psychological well-being than any other period of adulthood," he notes.

Conventional notions of aging largely have described it as an ongoing process of physical and cognitive decline, with little discussion about mental health, except in the context of decline. It broadly has been assumed that the mental health of older people mirrors their worsening physical and cognitive function. "Some investigators have reported a U-shaped curve of well-being across the life span, with declines from early adulthood to middle age followed by an improvement in later adulthood. The nadir of mental health in this model occurs during middle age, roughly 45 to 55. However, we did not find such a midlife dip in well-being."

The reasons for these differences in results are not obvious. There is measurement variation across studies, with different researchers emphasizing different indicators that, ultimately, produce different conclusions. Nonetheless, the commonality Is in finding improved well-being in the...