People's mental abilities can begin to deteriorate from the age of 27 after peaking at 22, according to research.
Research into 2,000 healthy people aged between 18 and 60 over the space of seven years was undertaken by Professor Timothy Salthouse at the University of Virginia and used tests that are used by doctors to spot signs of dementia.
Participants had to solve puzzles recall words and story details as well as identify patterns in letters and symbols.
In nine out of 12 tests the average age at which the top performance was recorded was 22, while 27 was the first age when there was any notable decline.
The study has been published in the journal Neurobiology of Aging.
"Results converge on a conclusion that some aspects of age-related cognitive decline begin in healthy, educated adults when they are in their 20s and 30s," Professor Salthouse asserted.
Earlier this month, the University of Reading announced it is to host an international workshop designed to enable people with dementia through the use of new technologies.
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