Alzheimer's disease. Light micrograph of a section through the brain of a patient suffering from Alzheimer's disease. A senile plaque (large pink circle, lower left) is seen. Senile plaques are a feature of Alzheimer's. The nerve cells (neurones) in the brains of sufferers degenerate and die, leading to a deterioration in brain function. The plaques form when material from dying neurones accumulates around protein. Granulovacuolar degeneration (smaller, darker bodies), the presence of vacuoles in the neurones, is also seen. The vacuoles prevent the neurones from functioning. This is the hippocampus region of the brain. Magnification unknown.