Schizophrenia - marked by delusions, hallucinations, and cognitive deficits - causes the most disability of any mental health condition, but existing treatments have significant side effect burden and are often ineffective. Disordered neural activity in the hippocampus likely contributes to schizophrenia symptoms, but to develop better therapies we need to understand whether hippocampal activity in schizophrenia can be systematically affected by non-invasive brain stimulation techniques like transcranial magnetic stimulation (TMS). This proposal will investigate the use of connectivity-guided theta burst brain stimulation to specifically target hippocampal function in schizophrenia, offering insights into fundamental hippocampal processes, schizophrenia pathophysiology, and potential avenues to use brain stimulation as a therapeutic tool in this devastating illness.

Inclusion Criteria:

• Men and women, ages 18 to 65 years
• Medically intractable epilepsy requiring phase II monitoring (intracranial EEG arms only)
• DSM-V diagnosis of schizophrenia spectrum Axis I disorders including delusional disorder, brief psychotic disorder, schizophreniform disorder, schizophrenia, schizoaffective disorder (non-invasive TMS-EEG arms only).
• Must have intellectual capacity to ensure adequate comprehension of the study and potential risks involved in order to provide informed consent
• No current or history of major neurological disorders other than epilepsy.

Exclusion Criteria:

• DSM5 diagnosis of intellectual disability
• Significant head injury
• Active suicidal ideation or history of suicide attempt within the past 1 year.
• Medical illness affecting brain structure or function, or other uncontrolled or unstable medical condition.
• Pregnancy or postpartum (<6 weeks after delivery or miscarriage)
• Inability to provide informed consent
• Active substance abuse other than alcohol or cannabis within the past 1 year
• Psychotic illness with a temporal relation to substance use or head injury
• Those with a contraindication for MRIs or TMS (e.g. implanted metal).

De-identified raw EEG and iEEG data will be shared.

Following publication of the data with no end date.

Anyone who wishes to access the data.