Women may experience cognitive aging in midlife, according to UCLA researchers.
A study, published in PLOS ONE earlier this month by UCLA scientists, revealed that middle-aged women exhibit significant declines in processing speed and verbal memory.
UCLA researchers analyzed data relating to cognitive health from the Study of Women’s Health Across the Nation, a long-term study co-funded by the National Institutes of Health. Participants were women between 42 and 52 years of age.
Statistical analysis of selected SWAN results revealed an average decline in cognitive speed and verbal episodic memory. Scientists determined cognitive processing speed by measuring how fast participants were able to match numbers to corresponding symbols. Researchers tested the strength of verbal episodic memory by evaluating participants’ ability to recall story details from a paragraph read to them.
The study contradicted previous research, which had found improvement in cognitive performance in middle-aged women. The research team developed controls to counter various variables that affected past studies’ results, said Arun Karlamangla, the lead author of the study.
One variable is practice effects, which means that participants’ performances change with repeated testing.
“You want to see the real underlying decline,” said Karlamangla. “The practice effects is a measurement artifact, it isn’t an actual reflection of cognitive function.”
Another factor that could have negatively affected the results of previous studies is the inclusion of women going through menopausal transition, which may impair participants’ performance.
To prevent these factors from affecting their analysis of SWAN data, UCLA researchers implemented different controls.
“What was unique about our study was that we were able to eliminate both (factors),” Karlamangla said.
Karlamangla said he thinks future research should identify the exact factors that influence the rate of cognitive decline and then develop interventions for cognitive aging.
However, Karlamangla said he also thinks the research results should not cause too much worry and that cognitive declines do not necessarily predict dementia.
“Don’t begin to lose your cool or (get) anxious because you forgot where you left your keys,” Karlamangla said.