Stress affects older adults more than young ones

Oct 28 2008

Experts on aging say stress affects older adults more than young adults.

A study by researchers at the University of Southern California (USC) has found that older adults change their behaviour more than young adults when under stress and this is particularly so in situations which involve risk.

The new study examined how stress affects decision-making and found that stressed older drivers are three times more likely to brake than calm drivers.

Lead author of the study Dr. Mara Mather says there is very little information about this whole topic, and even less when you get to age differences and how stress affects decision making has not been examined.

Dr. Mara Mather from the USC Davis School of Gerontology and colleagues exposed young adults (18 to 33) and older adults (65 to 89) to a stressful event, in this case, holding a hand in ice-cold water for three minutes.

The participants were then asked to play a driving game correlating to a real-life situation in which taking a small amount of risk is common - whether to go for it on a yellow light.

The participants started at a green light, and points were awarded for every second spent driving during a yellow, but lost if the light turned red while driving and the length of time for the yellow lights was determined randomly.

Dr. Mather says the participants had to decide to take some risk - driving during a yellow light - to score any points at all which is often the way in real life.

The researchers found in the control group, which was not exposed to ice-cold water, that older adults were actually better drivers than younger adults, scoring higher on the game - however, in the stressed group, older adults were not only more cautious but were also jerkier drivers, braking and restarting almost three times as much as their calmer peers.

The researchers found the differences in the effects of stress were consistent even when gender, level of education, mood and health self-ratings, were accounted for.

Dr. Mather says everyday driving can be stressful and the results indicate that stress changes older adults' strategies.

The exposure to ice-cold water caused a rise in levels of the hormone cortisol, measured in saliva, which increased significantly (and about the amount) among stressed younger and older adults, but did not change significantly from pre-test levels for the control group, which was not exposed to ice-cold water.

Mather says the brain regions that are involved in and activated by stress overlap quite a lot with the brain regions that are involved in decision making and, in particular, in decisions about risk.

The study was supported by the National Institute of Aging and is published in the journal Psychological Science.