MODEL RELEASED. Alzheimer's disease research. Researcher uses a binocular microscope to view a specimen of brain with Alzheimer's disease. Alzheimer's disease causes senile dementia in humans, the symptoms of which include memory loss, disorientation, personality changes and delusion, eventually resulting in death. The observable physiological changes of Alzheimer's include shrinking of the brain due to the degeneration and death of nerve cells, deep folding in the surface of the brain, tangled protein filaments (neurofibrillary tangles) within nerve cells and lesions of beta-amyloid protein in the brain.