Alzheimer's disease. Coloured three-dimensional magnetic resonance imaging (MRI) scan of the brain of an Alzheimer's disease sufferer. The widespread destruction of the brain tissue has lead to brain shrinkage and abnormally-deep folds (sulci), such as at centre right. The disease leads to memory loss and disorientation, and is the most common cause of senile dementia. Alzheimer's disease has no known cause and there is no cure. MRI scanning uses a powerful magnetic field and radio pulses to produce slice images of the body. Adjacent slices can be merged into a 3-D image on a computer. This scan was produced at the Laboratory of Neuro Imaging (LONI) at UCLA, USA.