A team of researchers at Northwestern University have found that football players who have high levels of stress hormone cortisol — which is released during strenuous exercise and which can increase a player’s risk of developing Alzheimer’s disease — experience more cognitive impairment, especially in areas related to the learning process.
The research, published in the Journal of Neuropsychopharmacology, was based on a small study that compared the performance of the participants during a test known as the Stroop Color Memory Test.
The test measures a player by using the Stroops color-imaging system to analyze how well they can recognize and remember a series of words.
Researchers measured the participants’ levels of cortisol as well as their memory scores using a brain scanner.
Cortisol was higher among the participants who were stressed more than the control group.
“Our findings suggest that high levels in cortisol could have a significant impact on cognition,” said study lead author Daniel G. Bock, a professor of psychiatry at Northwestern and an associate professor in the department of psychiatry and behavioral sciences.
“This study indicates that cortisol may be involved in the development of cognitive impairment.”
The researchers looked at three separate tests that measure cognitive function: the Strooper Color Memory Task, a cognitive test that measures a players ability to remember the Stroopers color-coded letters, and the Stroopa Color Memory task, which measures how well the player can quickly recall an image of a white square.
They also looked at participants’ mental health status, and how they were doing on a battery of cognitive tests.
“The results are interesting because it suggests that the effects of stress hormones on cognitive function could be different in men than in women,” Bock said.
“For instance, women who were tested during pregnancy and lactation showed a greater impact on the cognitive function tests, and also were more likely to have elevated levels of both cortisol and testosterone than women who had not been tested during those phases of their lives.”
The authors also looked specifically at whether there were any differences in the effect of cortisol levels between men and women, and they found that there was.
The authors say this is consistent with the idea that women tend to be more stressed than men.
“It is important to note that this is a relatively small study and it is not an experiment that has been replicated in a larger sample,” Bocks said.
In a separate study published in January in the journal Neuropsychologia, researchers at the University of California, San Francisco, compared cortisol levels in the brains of men and those of women during a period of stress.
They found that the differences were not significant, although they did note that the study was correlational.
In the current study, the researchers looked specifically for correlations between cortisol levels and cognitive function, and their findings showed that, indeed, there was a significant correlation between cortisol and cognitive impairment.
The researchers also looked for correlations with the number of years that the participants had been diagnosed with dementia, and again, the findings were not statistically significant.
In addition to the study of the Stroopy Color Memory test, the study looked at a different test called the Stroope Color Memory Scale, which is used to evaluate memory.
The tests measures the speed at which you can remember a word, which can be a measure of memory ability.
The researchers say the Strooped Color Memory tests are used for screening Alzheimer’s patients, as well.
The Stroop tests, the Stroopes, were also used to compare participants’ cognitive function with those of the control participants.
The findings are also important because it may be important for people with Alzheimer’s to know how their stressors affect cognitive function in general, Bock noted.
The study was funded by the National Institute of Mental Health and the National Institutes of Health.