Dutch researchers gave MRI scans to 142 people in an attempt to investigate some of the changes in the structure of the brain associated with Alzheimer's disease. They scanned 64 people with Alzheimer's disease, 44 people with mild cognitive impairment and 34 people with no memory or thinking problems once at the start of the study and again around a year and a half later. They measured the volume of the whole brain and of an area called the hippocampus and calculated the rate of shrinkage of the brain over the course of the study. Those people who were unaffected at the start of the study but who had smaller hippocampi and higher rates of brain shrinkage were two-four times as likely to develop dementia a year and a half later.
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