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Network-Targeted Neuromodulation for Nicotine Dependence in Schizophrenia

Not Applicable
Recruiting
Conditions
Schizophrenia
Nicotine Dependence
Interventions
Device: Repetitive Transcranial Magnetic Stimulation (rTMS)
Registration Number
NCT06389266
Lead Sponsor
Vanderbilt University Medical Center
Brief Summary

The goal of this clinical trial is to compare two active types of transcranial magnetic stimulation in two nicotine-using populations: nicotine-using people with psychosis and nicotine-using people without a diagnosis of a psychotic disorder. The main questions it aims to answer are:

1. Can rTMS change functional connectivity in brain circuits associated with nicotine use?

2. Are those rTMS-induced changes in functional connectivity related to craving?

Participants will complete tasks assessing their cognitive performance and craving before and after each week of TMS. Researchers will compare the effect of each TMS intervention on participants with and without psychosis to see if one type of TMS has an effect on nicotine craving.

Detailed Description

This study proposes to test the hypothesis that the brain circuits most relevant to nicotine use in schizophrenia are distinct from pathways identified in nicotine-using people without psychosis. This study seeks to provide evidence that targeted stimulation of the Default Mode Network (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 left dorsolateral prefrontal cortex (L DLPFC) leads to these changes in nicotine-using people without psychosis.

The investigators will test this hypothesis in a crossover design comparing 1) DMN-targeted continuous theta burst stimulation (cTBS) and 2) L DLPFC-targeted intermittent theta burst stimulation (iTBS). cTBS and iTBS are types of rTMS. cTBS has inhibitory effects and reduces functional connectivity, while iTBS is excitatory and increases connectivity (Huang et al. 2005). By applying cTBS to the DMN, a target that modulates craving in schizophrenia, the investigators expect DMN connectivity to decrease, thereby decreasing craving. Excitatory stimulation (e.g. iTBS) to the L DLPFC reduces craving in smokers without psychosis (Tseng et al. 2022).

This study will test a model that integrates brain network pathophysiology and cognition to 1) explain the prevalence of nicotine 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.

Aim 1: Target Engagement: Determine if rTMS manipulates functional connectivity of each target (DMN, L DLPFC) (n=60). Hypothesis 1A: Functional connectivity of the entire DMN will decrease after 5 days of DMN-targeted cTBS. Hypothesis 1B: Functional connectivity of the L DLPFC to the left insula will increase after 5 days of L DLPFC-targeted iTBS. As an exploratory hypothesis, the investigators will test if there is an effect of diagnosis on connectivity change.

Aim 2: Clinical Efficacy: Determine if rTMS affects cue-induced craving and if craving change correlates with change in functional connectivity (n=60). Hypothesis 2A: Both DMN-targeted and L DLPFC-targeted rTMS will significantly reduce craving. Hypothesis 2B: Craving change will be correlated with functional connectivity change. As an exploratory hypothesis, in individuals with schizophrenia, DMN-targeted cTBS will be more efficacious than L DLPFC-targeted iTBS.

Aim 3: Determine if individual differences in rTMS-induced network connectivity change are explained by individual differences in network controllability (n=60). There is significant heterogeneity in individual response to rTMS, even with network-targeted approaches. This may be related to network controllability, a metric of the average input energy required to change brain state (Bassett and Sporns 2017). It is critical to understand predictors of network change for optimal rTMS target selection in clinical trials. Hypothesis 3: Individual differences in rTMS-induced change in DMN connectivity will be associated with average controllability of the DMN rTMS stimulation site.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
100
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
DMN-Targeted cTBS, Then L DLPFC-Targeted iTBSRepetitive Transcranial Magnetic Stimulation (rTMS)Participants will first receive continuous theta burst stimulation (cTBS) at 100% AMT targeted to an individual-specific map of the left parietal node of the default mode network for five consecutive days. cTBS will be administered in a pattern consisting of 1 60s train of 3 pulses at 50Hz, repeated at 5Hz, for a total of 600 pulses. There will then be a washout period of at least two weeks before starting the L DLPFC-Targeted iTBS. Participants will receive intermittent theta burst stimulation (iTBS) at 100% active motor threshold (AMT) anatomically targeted to the left dorsolateral prefrontal cortex for five consecutive days. iTBS will be administered in a pattern consisting of 2s trains of 3 pulses at 50Hz, repeated at 5Hz, every 10s for a total of 600 pulses.
L DLPFC-Targeted iTBS, Then DMN-Targeted cTBSRepetitive Transcranial Magnetic Stimulation (rTMS)Participants will first receive intermittent theta burst stimulation (iTBS) at 100% active motor threshold (AMT) anatomically targeted to the left dorsolateral prefrontal cortex for five consecutive days. iTBS will be administered in a pattern consisting of 2s trains of 3 pulses at 50Hz, repeated at 5Hz, every 10s for a total of 600 pulses. There will then be a washout period of at least two weeks before starting the DMN-Targeted cTBS. Participants will then receive continuous theta burst stimulation (cTBS) at 100% AMT targeted to an individual-specific map of the left parietal node of the default mode network for five consecutive days. cTBS will be administered in a pattern consisting of 1 60s train of 3 pulses at 50Hz, repeated at 5Hz, for a total of 600 pulses.
Primary Outcome Measures
NameTimeMethod
Resting-state functional connectivityBaseline to one week, and three weeks to five weeks

The investigators will evaluate the effect of DMN-targeted cTBS on functional connectivity of the left parietal node of the DMN and the entire default mode network. The investigators will also evaluate the effect of L DLPFC-targeted iTBS on functional connectivity of the L DLPFC.

Cue-induced cravingBaseline to one week, and three weeks to five weeks

The investigators will evaluate the effect of DMN-targeted cTBS and L DLPFC-targeted iTBS on self-reported craving before and after presentation of visual nicotine cues. Craving is measured on a scale from 0 to 10, with 10 being the highest level of craving.

Tiffany Brief Questionnaire of Smoking Urges (QSU)Baseline to one week, and three weeks to five weeks

The investigators will evaluate the effect of DMN-targeted cTBS and L DLPFC-targeted iTBS on QSU scores. The QSU-Brief has a range of 10-70, with higher scores indicating higher smoking urges.

Self-reported cravingBaseline to one week, and three weeks to five weeks

The investigators will evaluate the effect of DMN-targeted cTBS and L DLPFC-targeted iTBS on self-reported craving, measured by a Visual Analog Scale of nicotine craving. Craving is measured on a scale from 0 to 10, with 10 being the highest level of craving.

Secondary Outcome Measures
NameTimeMethod
Wisconsin Smoking Withdrawal Scale (WSWS)Baseline to one week, and three weeks to five weeks

The investigators will evaluate the effect of DMN-targeted cTBS and L DLPFC-targeted iTBS on self-reported withdrawal symptoms.The WSWS has a range of 0-112, with higher scores indicating higher withdrawal.

Fagerstrom Test for Nicotine Dependence (FTND)Baseline to one week, and three weeks to five weeks

The investigators will evaluate the effect of DMN-targeted cTBS and L DLPFC-targeted iTBS on nicotine dependence severity. The FTND has a range of 0-10, with higher scores indicating greater nicotine dependence.

Self-reported nicotine useBaseline to one week, and three weeks to five weeks

The investigators will evaluate the effect of DMN-targeted cTBS and L DLPFC-targeted iTBS on self-reported nicotine use, measured by the Timeline Follow Back and the Recent Substance Use Questionnaire.

Trial Locations

Locations (1)

Vanderbilt University Medical Center

🇺🇸

Nashville, Tennessee, United States

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