<qa>  What is the FSIGTT?This proposal aims to use a well-characterized procedure, the modified Frequently Sampled Intravenous Glucose Tolerance Test FSIGTT, to characterize the glucoregulatory effects of the two most commonly prescribed atypical antipsychotic medications, risperidone and olanzapine, in comparison to the conventional antipsychotic haloperidol. Abnormalities in peripheral glucose regulation and type 2 diabetes can occur more commonly in individuals with schizophrenia than in healthy subjects or in other psychiatric conditions. While abnormalities in glucose regulation were first reported in schizophrenia prior to the introduction of antipsychotic medications, antipsychotic treatment may contribute significantly to abnormalities in glucose regulation. 