Some people who take the fast-acting sleep-aid zolpidem (Ambien) have been observed walking, eating, talking on the phone and even driving while not fully awake. Many often don't remember doing any of these activities the next morning. Similarly, this drug has been shown to awaken the minimally conscious into a conscious state. A new study by Georgetown University Medical Center (GUMC) researchers may help explain why these "awakenings" occur.