Methods and systems for analyzing a medical image of a subjects brain are disclosed. Analysis of a medical image of a subjects brain for predictive and diagnostic determination of neurodegenerative disease state. The method comprises parcellating the grey matter in the image of the brain and determining the size of each region to generate an initial pattern of the disease process applying a diffusion kernel to obtain an output vector and predicting future changes to the brain based on the output vector. Another method of analyzing a medical image of a subjects brain includes solving for eigen-modes of a connectivity matrix, projecting the eigen-modes onto the initial disease state to produce an output product and diagnosing a disease or lack thereof based on a comparison of the output product to one or more reference standards.