Patients without contraindications to Hyperbaric Oxygen treatment or magnetic resonance imaging who exhibit white matter hyper-intensities on MRI will be recruited to have a functional MRI followed by10 hyperbaric oxygen treatments at 2 ATA for one hour. These treatments will be done once daily, from Monday through Friday, on 2 consecutive weeks. 4-6 weeks later, they have a repeat fMRI. These fMRI's will be analyzed regarding any changes in the resting state connectivity of various circuits.