LONDON, Feb. 6 (Xinhua) -- The Alzheimer's disease could be spotted seven years before symptoms first appear with a memory test, researchers from Britain's University College London (UCL) found recently.

In the test, a group of 35 people were recruited, 21 of whom carry a mutation which puts them at higher risk of having Alzheimer's in their middle ages.

Participants were asked to remember a list of objects, details of a diagram, and some facts of a story. They were challenged to recall the information 30 minutes later and seven days later again.

The team found that those with the mutation -- in other words who were expected to develop Alzheimer's within seven years -- were able to pass the test at 30 minutes but not really at seven days.

"It appears to enable detection of Alzheimer's related memory problems much earlier than any other currently used cognitive test, with the individuals in our study being on average seven years away from the expected onset of any cognitive symptoms," said Dr. Phil Weston of UCL'S Medical Research Center Clinical Research Associate.

The Alzheimer's disease is an irreversible, progressive brain disorder that slowly destroys memory and thinking skills, and eventually the ability to complete some simplest daily tasks.

The trial was published on the recent edition of the scientific journal of The Lancet Neurology.