Stress of Task Strains Brain
It may dampen estrogen's influence on cognition in women, study finds
THURSDAY, Sept. 2, 2004 (HealthDayNews) -- The effect of estrogen on cognition is at least partially determined by the stress of individual mental tasks, says a University of Illinois at Urbana-Champaign study.
Many women considering estrogen therapy wonder whether it will help improve their brain functioning, the study authors noted.
"Will hormones help how your brain works -- how you think, your cognition? I wish I had a simple answer. It depends on many things about the task, and one of them is how stressful the task is. There is no simple translation to behavior," researcher Janice M. Juraska, a professor of psychology and of neuroscience, said in a prepared statement.
She and her colleagues found the introduction of a single stressor -- water temperature -- into a water maze prompted opposite reactions in female rats with either high or low levels of progesterone and estrogen.
"Water temperature totally reversed who did better. Proestrous rates, which have high hormone levels, did better when the water was warm, presumably because they were less stressed. Estrous rats did better when the water was cold, presumably because they are not as prone to get stressed during this time," Juraska said.
Estrous rats have low hormone levels and won't mate. Proestrous rats are fertile and ready to mate, Juraska said.
The results suggest the timing and duration of stress, as well as the memory systems involved in a task, may all influence the effects of ovarian hormones on performance.
The findings appear in the August issue of Behavioral Neuroscience.
The U.S. National Library of Medicine has more about estrogen.