People who have a clear sense of purpose are at a lower risk of developing Alzheimer's disease.
A study by researchers at the Rush University Medical Centre in Chicago found that people who had a greater purpose in life had better overall cognition than those with no direction, even when displaying a similar level of plaque in the brain.
High levels of plaque are often a marker for dementia and Alzheimer's disease.
Lead study author Dr Patricia Boyle and her colleagues followed 246 people who did not have dementia for up to ten years and performed brain autopsies when they subsequently died.
Plaques and tangles in the brain were then quantified and the team determined that greater focus meant they had a more limited impact.
"These findings suggest that purpose in life protects against the harmful effects of plaques and tangles on memory and other thinking abilities," Dr Boyle explained.
"This is encouraging and suggests that engaging in meaningful and purposeful activities promotes cognitive health in old age."
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