Researchers have determined different atrophy patterns in the brain may be able to explain various ways Alzheimer's disease can present itself in patients. The study was conducted by scientists from the Massachusetts General Hospital and the National University of Singapore. The authors say the neurodegenerative damage associated with the disease manifests itself in a variety of ways previous scholars have overlooked. Thomas Yeo said in a press release, "The symptom severity and neurodegeneration can vary widely across patients in Alzheimer's disease." Study participants exhibited at least three atrophy patterns -- cortical, temporal or subcortical. Those with mainly temporal atrophy had greater memory problems, while those with cortical atrophy had difficulties with executive function. The researchers' findings were published online in the Proceedings of the National Academy of Sciences.