 Basic science and clinical data suggest that activation of one or more of the brains arousal pathways is a highly plausible way to induce active emergence from general anesthesia. The investigators have compelling experimental data demonstrating that methylphenidate is highly effective in actively inducing emergence from isoflurane and propofol general anesthesia in rodents. The available literature suggests that IV methylphenidate would be safe to administer to patients recovering from general anesthesia, and that in addition to promoting arousal, it would enhance breathing. Both of these effects would be highly desirable in patients recovering from general anesthesia. 