A Randomized Placebo-Controlled Trial of Armodafinil (Nuvigil) for Fatigue in Patients With Malignant Gliomas

* Since no one knows for certain if armodafinil improves fatigue in brain tumor patients undergoing radiation therapy, participants will be randomized into one of two study groups. Half of the participants will receive armodafinil and the other half will receive pills with no medicine (placebo). Neither the participant or the study doctor will know what group they are in. * Participants will be given a study medication-dosing calendar and will take either the study drug or placebo orally once a day for 8 weeks. The dose will be adjusted on days 8,22 or 43, depending upon the level of fatigue. Treatment will begin within 10 days from the radiation start date. * Participants will be evaluated via documented clinician telephone call and self-administered questionnaires on days 1, 8, 22, 43 and 57.