Washington, Jul 17 (PTI): Stressful life experiences such as divorce, death of a child or job loss can age the brain by several years, a study claims.

Researchers examined data of 1,320 people who reported stressful experiences over their lifetime and underwent tests in areas such as thinking and memory.

The average age of the subjects' was 58 years and included 1,232 white Americans and 82 African Americans.

Researchers from Wisconsin University in the US also found that African American experienced 60 per cent more stressful events than white people during their lifetimes.

Each stressful experience was equivalent to about four years of cognitive ageing in African Americans, researchers said.

A series of neuropsychological tests examined several areas, including four memory scores (immediate memory, verbal learning and memory, visual learning and memory, and story recall).

Stressful life experiences included incidents such as losinga job, the death of a child, divorce or growing up with a parent who abused alcohol or drugs.

The results showed that a larger number of stressful events was linked to poorer cognitive function in later life, 'The Guardian' reported

"Studying the role of stress is complex. It is hard to separate from other conditions such as anxiety and depression, which are also thought to contribute towards dementia risk," Doug Brown, director of research at the Alzheimer's Society in the UK.

"We know that prolonged stress can have an impact on our health, so it's no surprise that this study indicates stressful life events may also affect our memory and thinking abilities later in life," he added.