Why Do People With Alzheimer’s Go Back in Time and ‘Relive’ Their Past?

People with Alzheimer’s disease may struggle to remember how they spent their morning, but still hold on to memories of their childhood. Sometimes they may even confuse caregivers for their parents or other people from their past.

This is a result of how memory is stored. The disease is known to attack the area of the brain called the hippocampus. Largely responsible for learning and making memories, a well-tuned hippocampus is required for retrieving data on everything from current world leaders to the contents of our bedroom closets. However, memories that stretch into one’s past are often housed in other parts of the brain outside the hippocampus, in the neocortex — which spares them from the disease’s initial blows.

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Some longer-term memories are stored outside the hippocampus, in the neocortex. (Credit: Blamb/Shutterstock)

“Alzheimer’s disease first affects the areas of the brain responsible for forming new memories,” says Rita Guerreiro, a neurogeneticist at the Van Andel Institute, a nonprofit biomedical research group based in Michigan. “People living with Alzheimer’s disease may hold onto old memories for some time after the onset of the disease.” But as the disease progresses, memory loss can worsen. As time goes on, “people may start to forget family members and be confused about space and time,” Guerreiro says.

This story is part of an ongoing series exploring questions about Alzheimer’s disease and dementia. Read more related to this topic: