To date, no investigators have examined the effects of low-dose anesthesia on functional connectivity. This study will image the human brain under conditions of rest, and low-dose anesthetic induced sedation. Quality of the acquired signals will be evaluated and functional networks in the brain will be examined. Of interest is whether administration of a low-dose anesthetic disrupts functional connectivity in the brain, and whether a disruption of functional connectivity is responsible for the reported analgesic and antidepressant effects of a anesthetic.