Forgetting the names of loved ones and the details of everyday life is a heart-breaking sign of Alzheimer's disease. While the scientific community once accepted that these memories were gone for good, a new study suggests they may not be "lost" - just inaccessible, and thus potentially retrievable.
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Researchers at MIT were able to stimulate the recall of certain memories in mice using blue light - a technique known as optogenetics.
Although the procedure is considered too dangerous for human trials, researchers are hopeful about the potential of being able to reverse early-stage Alzheimer's-induced memory loss in the future.
Nobel Prize-winning MIT neuroscientist Susumu Tonegawa, who led the research team, said: "The important point is, this a proof of concept. That is, even if a memory seems to be gone, it is still there. It's a matter of how to retrieve it."
Dr. Doug Brown, director of research at the Alzheimer's Society, told The Guardian: "While interesting, the practicalities of this approach - using a special blue light to stimulate memory - means that we're still many years away from knowing if it would be possible to restore lost memories in people."