3. Karnofsky performance status ≥60. 4. Ability to undergo MR imaging with the use of Gadolinium contrast. 5. Ability to undergo brain fMRI. 6. Patient must sign a study specific informed consent form. Patients who cannot provide consent due to cognitive impairment will not be enrolled in the study. The investigators will follow the recently published guidelines (Binder & Guze, Am. J. Psy., 155, 1649-1650, 1998) to assess the subject's understanding of the procedure and his/her decision making capacity,.