Schizophrenia is a serious and complex syndrome with heterogeneous symptoms that impacts more than 20 million people worldwide. This chronic and disabling disorder is thought to result from a complex interplay of genetic and environmental risk factors. Schizophrenia is characterized by positive symptoms (e.g. hallucinations and delusions), negative symptoms [e.g. blunted affect, alogia (reduction in quantity of words spoken), avolition (reduced goal-directed activity due to decreased motivation), asociality, and anhedonia (reduced experience of pleasure)] and cognitive deficits. Annual associated costs for schizophrenia are estimated to be more than $150 billion in the United States.
Current schizophrenia medications include antipsychotics, which work primarily through antagonism of the dopamine D2 receptor. These approaches do not impact the negative symptoms of schizophrenia, suggesting that dysfunction of the dopamine system might not fully explain the negative and cognitive symptoms associated with schizophrenia.
Animal, brain imaging, genetic, and postmortem brain studies have advanced our understanding of the underlying neurobiology of schizophrenia. The converging lines of evidence from these studies have implicated dysfunction in glutamate, a major excitatory neurotransmitter in the brain, as a potential cause of the disorder.