According to a study published in the issue of Neurology, the scientific journal of the American Academy of Neurology,people who are easily distressed and have more negative emotions are more likely to develop memory problems than more easygoing people.
In the study, those who most often experience negative emotions such as depression and anxiety were 40 percent more likely to develop mild cognitive impairment than those who were least prone to negative emotions. Mild cognitive impairment is a transitional stage between normal aging and dementia. People with mild cognitive impairment have mild memory or cognitive problems, but have no significant disability.
Researchers analyzed the results from two larger studies, the Religious Orders Study and the Memory and Aging Project, which involved 1,256 people with no cognitive impairment. During up to 12 years of follow-up, 482 people developed mild cognitive impairment.
Participants were evaluated on their level of proneness to distress and negative emotions by rating their level of agreement with statements such as 'I am not a worrier,' I often feel tense and jittery,' and 'I often get angry at the way people treat me.'
'People differ in how they tend to experience and deal with negative emotions and psychological distress, and the way people respond tends to stay the same throughout their adult lives,' said study author Robert S. Wilson, PhD, of Rush University Medical Center in Chicago, IL. 'These findings suggest that, over a lifetime, chronic experience of stress affects the area of the brain that governs stress response. Unfortunately, that part of the brain also regulates memory.'
An earlier study by Wilson and his colleagues showed that people who are easily distressed are more likely to develop Alzheimer's disease than more easygoing people.
Wilson said several factors lead researchers to believe that proneness to stress is a risk factor for memory problems and not an early sign of disease. For example, while the level of distress does not appear to increase in old age, the changes in the brain related to memory problems and Alzheimer's disease do increase with age.