When combined with results of other neurological tests, and in the context of a thorough medical history, atrophy of the brain (shown here in an MRI scan) sometimes indicates Alzheimer's. Simon Fraser/Science Source hide caption

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Dr. Joel Policzer checks on his patient, Lillian Landry, in the hospice wing of an Florida hospital in 2009. A new study found that many terminally ill cancer patients don't fully understand their prognosis. J. Pat Carter/AP hide caption

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