1. A method of registering an image volume of a brain of a living subject to a cortical surface of at least one targeted region of the brain of a living subject, comprising the steps of: a. pre-operatively acquiring the image volume from the brain of the living subject; b. generating a grayscale encoded brain surface from the acquired image volume; c. intra-operatively obtaining a textured point cloud of the cortical surface of the at least one targeted region of the brain of the living subject; and d. aligning the grayscale-encoded brain surface to the textured point cloud of the cortical surface so as to register the image volume of the brain with respect to the cortical surface of the at least one targeted region of the brain.