There are additional theoretical beliefs in regard to this study as well. A secondary hypothesis of this study is that quetiapine will have less extra pyramidal side effects (EPS) and less prolactin-related side effects than risperidone. A third hypothesis is that quetiapine will lead to less weight gain than olanzapine and risperidone. Finally, it is hypothesized that because of the fewer side effects, quetiapine will be better tolerated than risperidone and olanzapine.