Patients with schizophrenia spectrum disorder (SSD) will be exposed to active and sham repetitive transcranial magnetic stimulation (rTMS) in separate sessions. SSD-related biomarkers will be assessed before and after the rTMS administration.

Electrical neural oscillations of the brain can be measured at many levels, ranging from single cell to local field potentials in animals, to large-scale synchronized activities in the human scalp. New evidence suggests that there may be common underlying abnormalities in oscillatory activities that are associated with schizophrenia-related cognitive and functional impairments. There is currently no treatment for these electrical oscillation dysfunctions. Transcranial magnetic stimulation (TMS) provides a non-invasive means for altering brain electrical neural activity. TMS has been approved by FDA for the treatment of depression and many other mental disorders. It has been used in a wide range of clinical research, especially in neurology and psychiatry. The investigators aim to develop TMS paradigms that will modulate brain responses during basic sensory to more complex cognitive performance and determine the parameters in anatomic locations and TMS modalities that may effectively and safely modulate neural activities. If the current experiments successfully identified TMS methods/paradigms that improve neural oscillation and cognitive performances in schizophrenia patients, in the future (not part of the current protocol), the investigators can then develop specific TMS treatment that may correct abnormal brain function and improve cognition and clinical symptoms of schizophrenia.

Inclusion Criteria:

• Male and Female between ages 18-65
• Ability to give written informed consent (age 18 or above)
• Diagnosed with schizophrenia-spectrum disorder and Evaluation to Sign Consent (ESC) above10.

Exclusion Criteria:

• Any history of seizures.
• Significant alcohol or other drug use (substance dependence within 6 months or substance abuse within 1 month) other than nicotine or marijuana dependence.
• Any major medical illnesses that may affect normal brain functioning. Examples of these conditions include, but not limited to, stroke, CNS infection or tumor, other significant brain neurological conditions.
• Taking > 400 mg clozapine/day
• Failed TMS screening questionnaire
• Cardiac pacemakers, implanted medication pumps, intracardiac lines, or acute, unstable cardiac disease, with intracranial implants (e.g. aneurysm clips, shunts, stimulators, cochlear implants, or electrodes) or any other metal object within or near the head, excluding the mouth, that cannot be safely removed.
• History of head injury with loss of consciousness over 10 minutes; history of brain surgery
• Can not refrain from using alcohol and/or marijuana 24 hours or more & cigarette smoking half and hour or more prior to experiments.
• Woman who is pregnant (child-bearing potential but not on contraceptive and missing menstrual period; or by self report; or by positive pregnancy test) or has had unprotected sexual intercourse without birth control in the last 4 weeks.

From baseline to the time when the participant completes or quits the study (up to 1 month).