Secondary aims are to assess LY500307 effects on regional brain activation and connectivity during working (2-Back visual-verbal working memory task) and episodic (scene encoding and recognition)and memory tasks, and to evaluate electrophysiological indices of auditory sensory processing and working memory (auditory steady state responses, mismatch negativity (MMN) and auditory P300). It is predicted that LY500307 will produce greater increases than placebo in brain activity in prefrontal cortex and hippocampus during the working memory and episodic memory tasks, respectively, connectivity during resting fMRI, as well as increases in power of the auditory steady state response, MMN amplitude and P300 amplitude. The fMRI and electrophysiological measures will provide evidence of target engagement of LY500307 in schizophrenia and will be assessed as potential biomarkers for future clinical trials. Additional secondary aims will include assessing the effects of LY500307 on safety, positive symptoms, depression, social functioning and quality of life.