The technique, named HipMask and developed by neuroscientist Lisa Mosconi and her team, uses a brain scanning technique called PET. This involves injecting weakly radioactive glucose into the blood and measuring where it accumulates in the brain.
Glucose is used as ‘fuel’ by the brain, so brain activity in a particular location can be inferred from measuring the levels of radioactivity.
Mosconi’s team have discovered that poor levels of activity in a brain area called the hippocampus, a crucial memory area, predict the onset of Alzheimer’s disease up to 9 years before standard diagnosis.
Because the hippocampus is small and hidden deep within the brain, measuring its activity has been traditionally considered quite hard, as it produces a relatively weak signal.
Mosconi’s team overcame this problem by also using an MRI scan of the brain, which gives a more accurate internal picture, to complement the PET scan, which gives a clearer measure of hippocampal function.