Many different kinds of experiments support the hypothesis that memory is a brain process. I have
already mentioned the sad case of people with damage to the hippocampus who are unable to form
memories. When people with Alzheimer's disease lose their memories, autopsies show buildup of
plaques that have destroyed neural connections. Brain scans measuring the flow of blood to regions
as small as a few millimeters show what anatomical areas become active when people are presented
with stimuli of different kinds similar to ones they remember. Together, such experiments provide
strong evidence that when you remember something, it is because your brain has revived patterns of
neural activation.