Brain Stimulation During Sleep to Change Sleep Spindles in Schizophrenia

Trial details

Who runs it

University of Wisconsin, Madison

Trial code

NCT07680114

Record updated

1 October 2026

Original description

This study to find out whether a type of non-invasive electrical brain stimulation called transcranial electrical stimulation with temporal interference (TES-TI) can temporarily change brain activity during sleep-especially sleep spindles (brain rhythms in the ~8-16 Hz range). The investigators are focusing on the thalamus, a deep brain region that helps coordinate brain activity during non-REM sleep. Sleep spindles are often reduced in schizophrenia, so this study is to see whether TES-TI can change spindle activity in individuals with schizophrenia spectrum disorders (SSD) and in healthy adults. To study this, a structural MRI scan will be used to customize where the stimulation electrodes are placed, and then TES-TI will be applied during one of two overnight sleep lab visits while brain activity is recorded with high-density EEG and standard sleep sensors. The other overnight is a baseline/control night during which only sham stimulation is delivered. The goal is to determine whether TES-TI during sleep can increase spindle-frequency activity in this population.Read full original descriptionShow less

A Pilot Feasibility Study of Overnight Thalamic TES-TI to Modulate Sleep Spindles in Individuals With Schizophrenia Spectrum Disorders and Matched Healthy Controls

This study to find out whether a type of non-invasive electrical brain stimulation called transcranial electrical stimulation with temporal interference (TES-TI) can temporarily change brain activity during sleep-especially sleep spindles (brain rhythms in the ~8-16 Hz range). The investigators are focusing on the thalamus, a deep brain region that helps coordinate brain activity during non-REM sleep. Sleep spindles are often reduced in schizophrenia, so this study is to see whether TES-TI can change spindle activity in individuals with schizophrenia spectrum disorders (SSD) and in healthy adults. To study this, a structural MRI scan will be used to customize where the stimulation electrodes are placed, and then TES-TI will be applied during one of two overnight sleep lab visits while brain activity is recorded with high-density EEG and standard sleep sensors. The other overnight is a baseline/control night during which only sham stimulation is delivered. The goal is to determine whether TES-TI during sleep can increase spindle-frequency activity in this population.

Inclusion: U.S. citizen or holding permanent resident status; English-speaking; DSM-5 schizophrenia spectrum disorder (SSD) diagnosis, defined as schizophrenia, schizoaffective disorder, or schizophreniform disorder (confirmed by clinical interview and/or chart review); Chronic illness, defined as diagnosis of SSD for at least 1 year; Clinically stable outpatient (no psychiatric hospitalization in past 6 months; no change in antipsychotic medication in the past 6 weeks); Medically healthy (based on self-report and study team review); Matched to SSD participants on age (±5 years) and sex.

Exclusion: Dental implants; Current use of medications known to directly and substantially enhance sleep spindle activity, including benzodiazepines; non-benzodiazepine "Z-drug" hypnotics (zolpidem, eszopiclone, zaleplon); barbiturates; and gabapentin or pregabalin, within 2 weeks of the overnight study visits. Other sedating medications used as sleep aids (e.g., trazodone, hydroxyzine, mirtazapine) are permitted provided the regimen is stable across the two overnight visits; dose and timing will be recorded as covariates; Current use of any psychotropic medication, with the exception of a single SSRI or SNRI taken at a stable dose for at least 6 weeks for depression or anxiety. Current use of antipsychotics, tricyclic antidepressants, mirtazapine, trazodone, lithium or other mood stabilizers, benzodiazepines, non-benzodiazepine hypnotics, other anxiolytics, or stimulants will result in exclusion; Current or past history of clinically significant neurological disorder or acquired neurological disease (e.g., stroke, traumatic brain injury), including intracranial lesions (including clinically significant findings identified on the structural MRI); History of head trauma resulting in prolonged loss of consciousness; or a history of >3 grade I concussions; Any systemic illness or unstable medical condition that may cause a medical emergency in case of a provoked seizure (cardiac malformation, cardiac dysrhythmia, asthma, etc.); History of seizures, diagnosis of epilepsy, history of abnormal (epileptiform) EEG, or family history of treatment resistant epilepsy except for a single seizure of benign etiology (e.g. febrile seizures) in the judgment of a board-certified neurologist; Any medical devices or implants (i.e. cardiac pacemaker, medication infusion pump, cochlear implant, vagal nerve stimulator); Current use of medications known to substantially lower seizure threshold, specifically chlorpromazine, clozapine, bupropion, clomipramine, or maprotiline; or other medications at doses known to substantially lower seizure threshold in the judgment of the PI or Study Psychiatrist; Current moderate-to-severe alcohol or other substance use disorder (DSM-5) other than nicotine or caffeine; Active scalp lesions, broken skin, or skin conditions at planned electrode sites that would preclude safe electrode application; Sleep apnea or other sleep disorder (self-reported); Self-reported history of inpatient psychiatric hospitalization; Self-reported current or past diagnosis of schizophrenia or any other psychotic disorder; Self-reported first-degree relative with schizophrenia or any other psychotic disorder; Self-reported current or past diagnosis of bipolar disorder or major depressive disorder with psychotic features, or current treatment for any psychiatric disorder other than depression or anxiety (handled via the medication rule below); Active suicidal ideation, plan, or intent (assessed via PHQ-9 item 9 and follow-up Columbia-Suicide Severity Rating Scale (C-SSRS) Screener; see Safety Response Procedure); Inability to provide informed consent, including inadequate decisional capacity in the judgment of the study team and/or study psychiatrist; Current poorly controlled headaches, including intractable or frequent migraines; Possible pregnancy or plan to become pregnant in the next 6 months (self reported); Any metal in the head; Permanent retainers; Any hair braid, dreadlocks, hair pieces, or extensions which cannot be taken out before the study sessions; Any head coverings or headdress that participant feels uncomfortable removing for the purposes of study sessions; Claustrophobia (a fear of small or closed places); Back problems that would prevent lying flat for up to two hours; Regular night-shift work (second or third shift).

ClinicalTrials.gov NCT07680114