Whether cognitive decline occurs concomitant with reproductive decline and/or aging is unclear. Limited data gathered from studies of surgically or naturally menopausal NHPs suggest that estrogen states can modulate cognitive function in both young and old monkeys. However, the specific cognitive processes that may be influenced by estrogen may depend on age, with multiple domains being affected in older subjects. Although the findings of altered aspects of memory and attention processes in older, surgically menopausal monkeys mirror the findings obtained in several studies of nondemented postmenopausal women, it is difficult to directly relate the observations between monkeys and women because of differences in the instruments used to measure cognitive processes and the specific cognitive domains that have been measured between studies. canadian health & care mall
Also, because of greater access to brain tissue, NHP studies are more likely to reveal underlying mechanisms for altered cerebral blood flow or brain activation patterns seen in imaging studies from women at various stages of the menopausal process, or the effects of estrogen in postmenopausal women. For example, several studies have demonstrated similarities in menopause- and age-related changes in gene expression in the brains of surgically menopausal monkeys compared to those observed in autopsy studies of postmenopausal women.