New research suggests that a more positive outlook on aging could help reduce the risk of Alzheimer's disease. The study, carried out by the Yale School of Public Health, is the first to link these brain changes to a culturally based psychosocial risk factor.

To examine a possible link between dementia and negative beliefs on aging, the team of researchers looked at the brain MRI scans of healthy, dementia-free subjects from the Baltimore Longitudinal Study of Aging, the US's longest-running scientific study of aging.

The researchers found that participants who held more negative beliefs about aging showed one of the key brain changes associated with Alzheimer's -- a larger decline in the volume of the hippocampus, a part of the brain crucial to memory.

In addition the team used brain autopsies to examine two other indicators of Alzheimer's disease: amyloid plaques, clusters of protein clusters that build up between brain cells, and neurofibrillary tangles, twisted strands of protein that build up within brain cells.

The participants who had held more negative beliefs about aging, which had been measured 28 years previously, showed a significant increase in number of plaques and tangles.

Commenting on why negative beliefs would cause such a change, Becca Levy, who led the study, said, "We believe it is the stress generated by the negative beliefs about aging that individuals sometimes internalize from society that can result in pathological brain changes."

The results of the study suggest that combatting negative beliefs about aging, therefore reducing the stress that the beliefs cause, could be a possible way to protect against the disorder, with Levy adding that, "Although the findings are concerning, it is encouraging to realize that these negative beliefs about aging can be mitigated and positive beliefs about aging can be reinforced, so that the adverse impact is not inevitable."

The study was published online December 7 in the journal Psychology and Aging.