The aging of the Baby Boomers has inspired a lot of research into how we can stave off old-age cognitive decline. But a large new study suggests the most effective interventions may take place at the beginning of one's life.
It finds people who grew up in socially disadvantaged households—defined as crowded living quarters that are lacking in books—tend to score lower than others on tests of cognitive skills.
This gap apparently does not increase over time, but it remains significant after taking into account such factors as education, employment, and physical health. That suggests childhood poverty uniquely disrupts cognitive development, and the effect never fades away.
"We believe that the focus of strategies aiming to protect cognitive health should be shifted into childhood," lead author Pavla Cermakova of the Czech National Institute of Mental Health said in announcing the findings. "Children facing social and economic challenges should be provided with more resources to counter the disadvantages they face."
The study, published in the journal Neurology, featured data on 20,244 people from 16 European nations. Participants' average age was 71 at the start of the study. They were tested and interviewed at least twice, with the second session occurring about five years after the first.
Cognitive skills were measured by taking short tests that measured verbal fluency (by recording how well they were able to name specific animals) and delayed recall (in which they learned new words, and then were asked to recall them after a brief delay).
Their childhood living conditions were measured using three questions: the number of rooms in the home they lived in at age 10; the number of people who shared those rooms; and the number of books in the home. Using the ratio of people to rooms and the number of books as indicators, the researchers determined that 4 percent of participants experienced socioeconomic hardship in childhood.
"Adjusting for age, sex, and country of origin, childhood socioeconomic hardship was associated with lower cognitive scores," the researchers report. Further analysis found such factors as years of schooling and physical fitness accounted for less than half of this finding.
Follow-up tests conducted years later found the cognitive skills of people who grew up in poverty did not decline any faster than those of others. That suggests that, while a childhood of abundance seems to provide a real cognitive advantage up front, it is not a factor in warding off old-age cognitive decline.
While studies like this cannot definitely prove cause and effect, there seems to be something inherent in the living conditions of poor kids that impedes optimal cognitive development. Poverty, in short, appears to be bad for young brains.