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High Stress May Damage Memory According to a report issued in May 1998, elderly people who have consistently high blood levels of cortisol dont score as well on memory tests as their peers with lower levels of the stress hormone. Whats more, high levels of cortisol are also associated with shrinking of the hippocampus, a region of the brain that plays a key role in learning and memory. The finding suggest that even cortisol levels in the normal, healthy range can actually accelerate brain aging. The study results now pride substantial evidence that long-term exposure to adrenal stress hormones may promote hippocampal aging in normal elderly humans,write Nada Porter and Philip Landfield of the University of Kentucky in Lexington in their editorial. Cortisol is a hormone released in response to stress by the adrenal glands, which sit on top of the kidneys. Over a 5 to 6-year period, Dr. Sonia Lupien and his colleagues measured 24-hour cortisol levels in 51 healthy volunteers, most of whom were in their 70s. Despite wide variation in cortisol levels, the participants could be divided into three subgroups: those whose cortisol progressively increased over time and was currently high; those whose cortisol progressively increased over time and was currently moderate; and subjects whose cortisol decreased, but was currently moderate. The researchers tested the volunteers memory on six people in the increasing/high category and five people in the decreasing/moderate group. The groups did not differ on tests of immediate memory, but the increasing/high cortisol group had other memory problems compared with those in the decreasing/moderate group. | 
