This is a 6 week, randomized, open-label, parallel group study in patients with Bipolar-I disorder (manic depression), who are in remission from an episode. Participants who show cognitive impairment at baseline will be randomized to receive open-label Lurasidone added on to their current medication(s) or continue their usual treatment for 6 weeks. Participants will have 3 clinical visits and 2 telephone appointments during the study. Given the preliminary evidence for efficacy of Lurasidone in improving cognition in schizophrenia, we propose to examine the efficacy of Lurasidone in improving cognition in bipolar patients.