From the 'greatest generation' to the war babies, Americans' cognitive functions - mental skills like reasoning and memory - improved and were sustained at older age.
But new research shows that cognitive function among baby boomers is worse than that of their parents' or grandparents generations' when the scores of tests each group took around retirement age arre compared.
Data on more than 30,000 people spanning six generations reveals that early- and mid-baby boomers, who were born between 1948 and 1959, show more signs of mental decline than did their parents' or grandparents' generations.
Declining cognitive function is an early warning sign of dementia, including Alzheimer's, which is already depriving more than five million Americans of their memories and autonomy.
Researchers at Ohio State University blame the decline in mental function on greater poverty and loneliness and higher rates of depression and health problems like obesity and high blood pressure, which put both the heart and the brain at risk.
People in the pair of boomer generations are now between ages 62 and and 72, and signs of cognitive decline could be a bellwether that the crippling prevalence of Alzheimer's in the US is only going to swell as they enter old-age.
Cognitive function scores declined among aging baby boomers compared to war babies or the greatest generation, Ohio State University research found, signaling they could have higher rates of dementia
The children of the Great Depression were born between 1924 and 1930 and were raised by parents in the throes of the worst financial crisis the US has ever seen.
Financial woes meant more stress, less family or governmental investment in education and worse.
Rates of child desertion climbed into the mid 1930s, and an unprecedented number of families could scarcely afford to feed their children, leading to malnutrition which, in turn, can impair cognitive development and function later in life.
However, parents were also having fewer children, a decision which often leads to better care for and investment for a smaller number of kids in a household.
Meanwhile, Franklin D Roosevelt took office and changed the course set by the Hoover administration which had more or less turned a blind eye the impact of the Great Depression on Children.
A major federal relief programs as well as initiatives focused on bringing food and healthcare to even poorest, most rural children in America were launched as part of the New Deal, and childhood conditions began to improve favorably to mental development.
Education levels and occupation have improved over the generations, so the OSU study suggests these are not associated with declining mental function
Scores declined as much or more among baby boomers who are white