Long-Term Stress Could Hurt Memory
ByElevated levels of stress hormones can lead to short-term memory loss as people age, according to a recent study the Huffington Post reported.
Researchers from the University of Iowa found that having high levels of cortisol -- a natural hormone produced by the adrenal glands and surges when people are stressed -- can lead to memory lapses in older adults. Researchers said short-term memory lapses related to cortisol start around age 65.
"Stress hormones are one mechanism that we believe leads to weathering of the brain," Jason Radley, assistant professor in psychology at the UI and corresponding author on the paper, said in a statement.
Short-term increases in cortisol, commonly known as the stress hormone, are critical when a person is in survival mode. The hormone promotes coping and helps people respond to life's challenges by making people more alert and able to on their feet. But abnormally high or prolonged spikes in cortisol can lead to serious health issues such as weight gain, digestive troubles and high blood pressure.
For the study, researchers compared the elderly rats to four-month old rats, which are roughly the same age as a 20-year-old person. The young and elderly groups were then separated further according to whether the rats had naturally high or naturally low levels of corticosterone -- the hormone comparable to cortisol in humans.
They were subsequently placed in a T-shaped maze that required them to use their short-term memory. In order to receive a treat, they needed to recall which direction they had turned at the top of the T just 30, 60 or 120 seconds ago and then turn the opposite way each time they ran the maze.
In contrast, older rats with low corticosterone levels showed little memory loss and ran the maze nearly as well as the younger rats, who were not affected by any level of corticosterone -- low or high.
Researchers said it's important to remember that stress hormones are only one of a host of factors when it comes to mental decline and memory loss in older adults.
The findings were recently published in the Journal of Neuroscience.