Alzheimer's disease is the end result of gradual, progressive brain aging. Positron emission technology (PET) scans of patients' brains typically reveal a decreased rate of metabolism, a hallmark of the disorder.
A small sample of adults with mild age-related memory loss was randomly assigned a daily placebo or Aricept, a drug that treats Alzheimer's symptoms. Both groups underwent PET brain scans before and after 18 months of treatment. The brains of people given Aricept showed an increased rate of metabolism and looked more normal than the brains of those who took the placebo. Both groups scored the same on memory tests, however, implying that PET scans may be more sensitive than neuropsychological tests in detecting drugs' effects.
The research suggests that the treatment of early symptoms of memory loss may protect the brain and help people with mild age-related memory impairment. The finding also shows how PET offers researchers a tool for tracking the effectiveness of drugs prescribed to treat age-related cognitive decline.