RO-5545965

This is a multicenter, randomized, double-blind, placebo-controlled, three period crossover study to evaluate the effects of RO5545965 on the functioning of key brain circuitry involved in negative symptoms using functional magnetic resonance imaging (fMRI) and reward-based learning in stable participants with mild to moderate negative symptoms of schizophrenia treated with antipsychotics. Participants will be randomized to one of six different sequences during which each participant will receive three 3-week treatment courses with RO5545965 5 milligrams (mg), RO5545965 15 mg and placebo. Each treatment period will be separated by a washout period of 14 days. Total duration of study will be approximately 17 weeks.