Electrical brain stimulation using a noninvasive cap can help boost older people's mental scores to those of people 20 to 30 years younger, according to a study published on Monday.

The research, published in the journal Nature Neuroscience, found that age-related decline in working memory can be reversed by stimulating two key brain areas at a specific rhythm.

The findings are early and only relate to healthy volunteers at this stage, but could point to new ways to boost brain function in people with age-related cognitive decline such as dementia and Alzheimer's patients