Age

18–60

Sex

ALL

Healthy volunteers

Not accepted

are currently taking Risperdal and have been on the medication for at least three weeks
are diagnosed with schizophrenia
are able to provide written informed consent
can safely have an MRI

are treatment resistant or intolerant to Risperdal
have participated in another drug study in the past 28 days
are pregnant or trying to become pregnant or are breastfeeding
are colorblind
have a history of alcohol, cannabis, or cocaine abuse within two weeks prior to the study
have a current or past history of a major medical illness or have abnormal lab values which the study doctor feels is significant
certain medications are also exclusionary including aripiprazole.

Contrasting the Brain Effects of Risperidone and Invega With Functional Magnetic Resonance Imaging (fMRI) and Positron Emission Tomography (PET) Scanning