London, April 7 (Inditop) Young adults at risk of developing Alzheimer’s show changes in their brain activity decades before symptoms might arise, according to a new study.
The results may support the idea that the brain’s memory function may be gradually eroded in those who go on to develop Alzheimer’s.
The research by Oxford University and Imperial College scientists provides clues as to why certain people develop Alzheimer’s Disease (AD). It may be a step towards a diagnostic test that identifies individuals at risk.
The degenerative condition is the most common cause of dementia and it affects around 4,17,000 people in Britain alone.
The APOE4 genetic variant is found in about a fourth of the population. Not everyone who carries the variant will go on to develop AD, but people who inherit one copy of APOE4 have up to four times the normal risk of developing the late-onset variety of the disease.
People who have two copies have around 10 times the normal risk.
Researchers stress that most carriers of APOE4 will not go on to develop Alzheimer’s and carriers should not be alarmed by the study’s findings.
Differences in the region of the brain involved in memory, known as the hippocampus, have previously been shown in middle-aged and elderly healthy carriers of APOE4.
However, the new study is the first to show hyperactivity in the hippocampus of healthy young carriers. It is also the first to show that APOE4 carriers’ brains behave differently even at ‘rest’.
The study used functional magnetic resonance imaging (fMRI), carried out at the University of Oxford to compare activity inside the brains of 36 volunteers, with 18 carrying at least one copy of the APOE4 gene and 18 non-carriers acting as controls.
All the volunteers in the study were aged between 20 and 35 and all performed normally on tasks designed to test their cognitive skills, said an Imperial College release.
These findings were published in the Monday edition of the Proceedings of the National Academy of Sciences.