Schizophrenia is a severe mental illness associated with hallucinations and delusions (positive symptoms), emotional withdrawal and decreased expressivity (negative symptoms), and problems with memory, attention, and social interaction (cognitive impairment). Positive symptoms, the most recognizable characteristics of the illness, can be treated effectively with available antipsychotic medications. Cognitive deficits and negative symptoms, however, are more closely related to functional outcome in schizophrenia, and yet, there is no approved treatment for these types of deficits (1,2).