RecruitingNot applicable

Precision Brain Stimulation to Reduce Cannabis Craving in Schizophrenia

Who can join

As published by the study on ClinicalTrials.gov. "Not stated" means the study hasn't said — ask the study team.

Age
18 Years to 65 Years
Sex
All sexes
Healthy volunteers
Accepted
Compensation
Mentioned in the study description

Other requirements are listed under Eligibility below. Only the study team can confirm whether you can join.

What to expect

No one can promise a trial will help you personally — that is what the research is trying to find out.

What participation involves

  • Time periods mentioned: 5 days
  • Procedures mentioned: MRI scans

Only what the study's summary and detailed description on ClinicalTrials.gov say. Time periods may describe the whole study or a part of it — ask the study team what applies to you.

Show the study's own words
  • "Function of brain networks can be measured in the MRI scanner."
  • "However, the FDA recently cleared the SAINT protocol for depression, which involves a total of 50 sessions over 5 days (10 sessions/day)."
  • "In Prelim Data #3, individuals with SZ received single sessions of Default Mode Network-targeted cTBS (active and sham) with MRI immediately before and after rTMS."
  • "As pilot data for the proposed study, individuals with SZ underwent 5 daily sessions of 1) Default Mode Network-targeted cTBS and 2) Conventional DLFPC-targeted iTBS in a crossover design with MRI and craving assessment before and after each rTMS week."
Compensation
Mentioned in the study description
  • Study-related exams and procedures are typically provided at no cost. This is how many trials work in general — confirm the details for this study with the study team.
  • Participants are monitored closely by the research team throughout the study.
  • Some participants may receive access to an investigational treatment, which is still being studied.
  • Your participation helps researchers learn whether this approach could help future patients.

About this study

In plain language

This study tests two types of rTMS, a treatment that uses magnetic pulses to stimulate the brain. It looks at effects on cannabis cravings, thinking skills, and how parts of the brain work together. It is for adults who use cannabis, including people with schizophrenia or schizoaffective disorder and people without a psychotic disorder.

The central hypothesis is this: Brain circuits most relevant to cannabis use in schizophrenia are distinct from pathways identified in healthy controls who use cannabis. This study seeks to provide evidence that targeted stimulation of the DMN leads to both altered network activity and a concomitant behavioral change in cue-induced craving and cognitive performance in individuals with schizophrenia and schizoaffective disorder, while targeted stimulation of the L DLPFC leads to these changes in healthy controls who use cannabis. This study will test a model that integrates brain network pathophysiology and cognition to 1) explain the prevalence of cannabis use in schizophrenia and 2) identify a target for engagement in schizophrenia. This study seeks to establish a neuroscientific framework to guide future treatment-oriented studies aimed at reducing craving and improving cognitive performance in individuals with schizophrenia and schizoaffective disorder. This is a study of the effect of 2 rTMS interventions on functional connectivity and craving in individuals with schizophrenia or schizoaffective disorder and healthy controls who use cannabis. Aim 1: Target Engagement: Determine if rTMS manipulates functional connectivity of each target (DMN, L DLPFC) (n=100). Aim 2: Clinical Efficacy: Determine if rTMS affects cue-induced craving and if craving change correlates with change in functional connectivity (n=100). As an exploratory analysis, the factors that explain individual variance in rTMS-induced connectivity change will also be explored.

Compensation is read from the study's own description and may be missing — always confirm with the study team.

Eligibility

Who can join

  • Be 18 to 65 years old.
  • For the psychosis group: have a confirmed psychotic disorder, which can affect how you see or understand reality.
  • For the comparison group: have no psychotic disorder and no parent, sibling, or child with one.
  • Currently use cannabis, confirmed by a urine test, and rate current use at least 2 out of 10 on the study scale.
  • Be able to read, speak, and understand English.
  • Study staff must believe you can complete the study tasks.
  • Be stable and in outpatient mental health care, with no mental health hospital stays or psychiatric medicine changes in the past 30 days.

Who can't join

  • An intellectual disability, or a substance use disorder involving drugs other than cannabis or nicotine in the past 3 months.
  • A urine test showing cocaine, benzodiazepines, amphetamine, or methamphetamine.
  • A brain or nerve disease, stroke, brain injury, or brain tumor; or a head injury causing more than 15 minutes of unconsciousness or lasting nerve or brain problems.
  • Poorly controlled headaches or ongoing medicine to prevent migraines; unexplained fainting that could be seizures; or seizures, epilepsy, or a parent, sibling, or child with epilepsy. A specialist may allow a single seizure with a harmless cause.
  • A long-term medical condition that could cause an emergency during a seizure, such as certain heart problems or asthma.
  • Metal in the brain, skull, or elsewhere in the body, except dental fillings, unless the study doctor approves it. Devices such as pacemakers, medicine pumps, or nerve stimulators also need approval.
  • Being pregnant or planning pregnancy. Participants who could become pregnant must take a pregnancy test.
  • Any medicine changes or hospital stays in the past 30 days. The study doctor will also review medicines for safety and may exclude anyone who is not suited for the study or cannot tolerate the visit.

Simplified for readability. The official criteria below are what the study team uses.

Official eligibility criteria

Inclusion Criteria for Psychosis Participants: * Age between 18-65 years * Diagnosis of a psychotic disorder according to DSM-5 criteria and confirmed by SCID * Current cannabis use of at least 2/10 on a Visual Analog Scale * Current cannabis use (confirmed by urine cannabis testing) * Must be able to read, speak and understand English * Must be judged by study staff to be capable of completing the study procedures * Participants will be in stable outpatient psychiatric treatment and psychiatrically stable with no recent (within the past 30 days) psychiatric hospitalizations or changes in their psychiatric medication regimens. Inclusion Criteria for Healthy Controls: \- All of the above except for participants will not have a diagnosis of a psychotic disorder nor a first-degree relative with a psychotic disorder. Exclusion Criteria for ALL participants: * DSM-5 intellectual disability * Substance use disorder (other than cannabis or nicotine) within the past three months * Positive urine drug screen for illicit substance use that can increase seizure risk (cocaine, benzodiazepines, amphetamine, methamphetamine) * Any history of a progressive or genetic neurologic disorder (e.g. Parkinson's disease, multiple sclerosis, tuberous sclerosis, Alzheimer's Disease) or acquired neurological disease (e.g. stroke, traumatic brain injury, tumor), including intracranial lesions * History of head trauma resulting in any loss of consciousness (\>15 minutes) or neurological sequelae * Current history of poorly controlled headaches including chronic medication for migraine prevention * History of fainting spells of unknown or undetermined etiology that might constitute seizures * History of seizures, diagnosis of epilepsy, or immediate (1st degree relative) family history epilepsy with the exception of a single seizure of benign etiology (e.g. febrile seizures) in the judgment of a board-certified neurologist * Chronic (particularly) uncontrolled medical conditions that may cause a medical emergency in case of a provoked seizure (cardiac malformation, cardiac dysrhythmia, asthma, etc.) * Any metal in the brain or skull (excluding dental fillings) or elsewhere in the body unless cleared by the responsible covering MD (e.g. MRI compatible joint replacement) * Any devices such as pacemaker, medication pump, nerve stimulator, TENS unit, ventriculo-peritoneal shunt unless cleared by the responsible covering MD * All female participants of child-bearing age will be required to have a pregnancy test; any participant who is pregnant or planning to become pregnant will not be enrolled in the study * Medications will be reviewed by the responsible covering physician and a decision about inclusion will be made based on the participant's past medical history, drug dose, history of recent medication changes or duration of treatment, and use of CNS active drugs. The published TMS guidelines review of medications to be considered with rTMS will be taken into consideration given their described effects on cortical excitability measures. * Any changes in medications or hospitalizations within the past 30 days. * Participants who, in the investigator's opinion, might not be suitable for the study or would be unable to tolerate the study visit These exclusion criteria strictly follow all recommended guidelines as endorsed by the International Federation of Clinical Neurophysiology and the International Society for Transcranial Stimulation.

Study sites (1)

TN