LONDON — Most of us probably don’t remember all of our test scores from the third grade. However, according to a new set of research, thinking and memory test scores recorded at age eight may predict how well individuals score on similar tests at age 70.
The study, conducted by researchers at the University College of London, also showed that education level and socioeconomic status can also serve as predictors of thinking and memory performance in old age.
“Finding these predictors is important because if we can understand what influences an individual’s cognitive performance in later life, we can determine which aspects might be modifiable by education or lifestyle changes like exercise, diet or sleep, which may in turn slow the development of cognitive decline,” says study author Dr. Jonathan M. Schott in a media release.
Dr. Schott and his team studied 502 British citizens born during the same week in 1946, all of whom had taken thinking and memory tests when they were eight years old. When these individuals were asked to take similar tests between the ages of 69 and 71, researchers noticed a positive correlation between their age-eight scores and their age-70 scores.
The tests included looking at various arrangements of shapes, and then identifying the missing shapes from subsequent options. Other tests focused on attention, memory, orientation, and language skills.
As a part of the study, participants also underwent positron emission tomography (PET) scans to determine if they exhibited any telltale signs of Alzheimer’s disease, particularly the dreaded amyloid-beta plaques typically found in Alzheimer’s patients’ brains. The researchers also conducted intensive brain magnetic resonance imaging (MRI) scans.
In most cases, the researchers found that individuals whose cognitive test scores were in the 25th percentile as a child, still scored in the top 25% at 70 years old.
But, the researchers found other factors that affected cognitive performance over time as well. After accounting for differences in childhood test scores, it was also noted that education had an effect. Study participants who completed a college degree scored 16% higher on average than those who dropped out of school before turning 16 years old. Socioeconomic status also appeared to affect test scores, but only marginally. Overall, women performed better than men in memory and thinking speed tests.
Unsurprisingly, Dr. Schott and his colleagues discovered that participants with evidence of Alzheimer-predicting amyloid-beta plaque build-up scored lower on cognitive testing. When the researchers tried to dig deeper and learn if a higher prevalence of plaque was associated with gender, education, socioeconomic status, or childhood test scores, they discovered no such correlation.
“Our study found that small differences in thinking and memory associated with amyloid plaques in the brain are detectible in older adults even at an age when those who are destined to develop dementia are still likely to be many years away from having symptoms,” says Schott. “It also found that childhood cognitive skills, education and socioeconomic status all independently influence cognitive performance at age 70. Continued follow-up of these individuals, and future studies are needed to determine how to best use these findings to more accurately predict how a person’s thinking and memory will change as they age.”
The results of the study were published in the online issue of Neurology®.