• INCLUSION CRITERIA:
• Diagnosis of DSM-IV- or DSM5-defined schizophrenia spectrum disorder (including schizophrenia, schizoaffective disorder, or other specified/unspecified schizophrenia spectrum and other psychotic disorder/psychosis NOS).

Subjects with other neuropsychiatric disorders may also be admitted and participate in the protocol if there is sufficient evidence to believe they have an underlying, undiagnosed DSM-IV-or DSM5-defined schizophrenia spectrum disorder.

EXCLUSION CRITERIA:

-Currently treated with depot medications

Because of the long half-life of depot medications such as paliperidone palmitate (Invega Sustenna), applicants to our program will be excluded if they are currently receiving depot medications monthly. However, applicants may decide to switch from depot to oral medications on their own, in conjunction with their personal physician, before coming to the program. This is not part of research and we do not participate in this decision. A sufficient washout period based on the particular long-acting injectable medication s elimination half-life will be required in order for prospective participants to be eligible. Subjects may complete the last 3 months of washout in the inpatient unit while being evaluated under the standard protocol.

-Major medical illness.

Research subjects identified as having major medical problems other than their primary neuropsychiatric disorder will be excluded from admission.

• Applicants judged to be unsuitable for medication free studies will also be excluded. Possible reasons for exclusion include prior history of dangerousness to self or others, particularly when off medication.
• Applicants who are pregnant are excluded from this study. Volunteers who are found to be pregnant after testing will be terminated from study and referred to an OB-GYN for follow up care.
• Infection with syphilis, hepatitis, or HIV.
• History of any (excepting nicotine-related and cannabis-related) DSM5-defined moderate to severe substance use disorder (or DSM-IV-defined substance dependence).
• Cumulative lifetime history of any (excepting nicotine-related and cannabis-related) DSM5-defined mild substance use disorder (or any DSM-IV-defined substance abuse), either in excess of 5 years total or not in remission for at least 6 months.
• Lack of capacity to provide consent.

Exclusion Criteria for Previously Enrolled Research Subjects

• No longer satisfying the above inclusion criteria or meeting any of the above exclusion criteria
• Inability to safely participate in planned research (e.g., development of acute suicidal behavior during prior research participation)
• Unlikely to provide sufficient additional research data