London: Scientists have devised a 10-minute, picture-based memory test which they claim could identify the initial signs of Alzheimer's disease earlier.
   
A team at Cambridge University says the Cambridge Cognition test picks up early stage Alzheimer's disease and a forerunner of dementia, known as mild cognitive impairment, before existing tests, by examining the part of the brain that starts deteriorating first, called the hippocampus.
   
It is tasked with remembering fleeting everyday details such as where one parked the car, or put one's keys, a function called episodic memory; daily quoted Prof Barbara Sahakian, a clinical neuroscientist at Cambridge University, as saying.
   
By contrast, the most widely-used cognitive test for dementia today, the mini-mental state examination (MMSE), examines a part which breaks down later in the course of Alzheimer's, called the temporal neocortex, she said.
   
With the new iPad-based test, patients are asked to recall the location on the iPad screen of different symbols that flash up briefly. The test gets progressively harder.
Participants first have to remember where a single symbol flashed up, in one of six possible boxes, while at the end they're asked to recall where six symbols were.

Research indicates the test is 95 per cent accurate at correctly distinguishing healthy people from those with mild cognitive impairment, and at telling those with MCI from those with Alzheimer's itself, say the scientists.
   
It identified people with cognitive impairment up to 32 months before they were officially diagnosed with Alzheimer's, said Dr Andrew Blackwell, chief scientific officer of the spin -off company that has developed the test.
   
If the test is adopted by doctors, it could mean far more people being prescribed drugs treatment.
   
Prof Sahakian believed the way forward was earlier treatment still, "We really want to be able to detect Alzheimer's disease very early and halt it at the stage when people are still functioning well. We don't want to be putting these drugs into people (only) when they have already declined."

(Agencies)