<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT03814967</url>
  </required_header>
  <id_info>
    <org_study_id>1344169</org_study_id>
    <secondary_id>UCD#3565</secondary_id>
    <nct_id>NCT03814967</nct_id>
  </id_info>
  <brief_title>Effects of Brain Stimulation on Higher-Order Cognition</brief_title>
  <official_title>Transcranial Direct Current Stimulation (tDCS) Studies of Behavioral and Electrophysiological (EEG) Correlates of Higher-Order Cognition</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>University of California, Davis</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>University of California, Davis</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>Yes</is_fda_regulated_device>
    <is_unapproved_device>Yes</is_unapproved_device>
    <is_us_export>No</is_us_export>
  </oversight_info>
  <brief_summary>
    <textblock>
      The purpose of this study is to better understand the neural correlates of higher-order&#xD;
      cognition, both in the healthy brain and in schizophrenia, and to determine how these&#xD;
      mechanisms are modulated by transcranial direct current stimulation (tDCS) at frontal and&#xD;
      occipital scalp sites. Testing the effects of tDCS at these scalp sites on cognitive task&#xD;
      performance will help us understand the roles of the brain regions corresponding to these&#xD;
      sites during higher-order cognitive processing (language comprehension, cognitive control,&#xD;
      and related attention and memory processes). Behavioral and electrophysiological (EEG)&#xD;
      measures will be used to assess cognitive performance. The investigator's overarching&#xD;
      hypothesis is that stimulating prefrontal circuits with tDCS can improve cognitive control&#xD;
      performance, and ultimately performance on a range of cognitive tasks, as compared to&#xD;
      stimulating a different cortical region (occipital cortex) or using sham stimulation. This&#xD;
      study is solely intended as basic research in order to understand brain function in healthy&#xD;
      individuals and individuals with schizophrenia. This study is not intended to diagnose, cure&#xD;
      or treat schizophrenia or any other disease.&#xD;
    </textblock>
  </brief_summary>
  <overall_status>Recruiting</overall_status>
  <start_date type="Actual">May 22, 2019</start_date>
  <completion_date type="Anticipated">January 31, 2024</completion_date>
  <primary_completion_date type="Anticipated">January 31, 2024</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Randomized</allocation>
    <intervention_model>Crossover Assignment</intervention_model>
    <primary_purpose>Basic Science</primary_purpose>
    <masking>Double (Participant, Investigator)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>EEG Correlates of Language and Cognitive Control</measure>
    <time_frame>Assessment will begin immediately following stimulation and last for about 1.5 hours.</time_frame>
    <description>Electrophysiological data recorded during completion of cognitive control and language comprehension tasks. We will measure oscillatory activity in the theta, alpha, beta and gamma frequency bands.</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Behavioral Response (Cognitive Control Task)</measure>
    <time_frame>Assessment will begin immediately following stimulation and last for about 1.5 hours.</time_frame>
    <description>We will assess performance on the Dot Pattern Expectancy (DPX) task (error rates and d-prime scores).</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Behavioral Response (Language Task)</measure>
    <time_frame>Assessment will begin immediately following stimulation and last for about 1.5 hours.</time_frame>
    <description>We will assess performance on a novel Language Comprehension task (accuracy and semantic relatedness judgement scores).</description>
  </primary_outcome>
  <number_of_arms>3</number_of_arms>
  <enrollment type="Anticipated">120</enrollment>
  <condition>Schizophrenia</condition>
  <arm_group>
    <arm_group_label>DLPFC Stimulation</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>Intervention. 20 minutes of 2 mA direct current stimulation over the dorsolateral prefrontal cortex.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Occipital Stimulation</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>Intervention. 20 minutes of 2 mA direct current stimulation over the occipital cortex.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Sham Stimulation</arm_group_label>
    <arm_group_type>Sham Comparator</arm_group_type>
    <description>Placebo Comparator. 0.5-1 minutes of 2 mA direct current stimulation over the dorsolateral prefrontal cortex followed by 19-19.5 minutes of sham stimulation</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>Transcranial Direct Current Stimulation</intervention_name>
    <description>In tDCS, saline-soaked electrodes are temporary affixed to the scalp and connected to a battery-powered current generator. A weak (2 mA) constant current is then briefly applied (~20 minutes) to stimulate the targeted brain area (e.g. the DLPFC). To control for placebo effects, the study will utilize a sham stimulation protocol that consists of very brief constant stimulation (~1 minute). Subjects usually cannot discern the difference between the sham and experimental stimulation protocols due to habituation.</description>
    <arm_group_label>DLPFC Stimulation</arm_group_label>
    <arm_group_label>Occipital Stimulation</arm_group_label>
    <arm_group_label>Sham Stimulation</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Participants must be able to sufficiently speak and understand English so as to be&#xD;
             able to understand and complete cognitive tasks.&#xD;
&#xD;
          -  All subjects must have the ability to give valid informed consent.&#xD;
&#xD;
        Inclusion Criteria for Patients with Schizophrenia Only:&#xD;
&#xD;
          -  Diagnosis of schizophrenia, schizophreniform or schizoaffective disorder&#xD;
&#xD;
          -  No medication changes in the prior month&#xD;
&#xD;
          -  No medication changes anticipated in the upcoming month&#xD;
&#xD;
          -  Stable outpatient or partial hospital status&#xD;
&#xD;
          -  Normal IQ (&gt;70; IQ will be measured by administering the Wechsler Abbreviated Scale of&#xD;
             Intelligence (WASI) test)&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Pacemakers&#xD;
&#xD;
          -  Implanted electrical (brain and spinal) stimulators&#xD;
&#xD;
          -  Implanted defibrillator&#xD;
&#xD;
          -  Metallic implants&#xD;
&#xD;
          -  Skin damage or skin conditions such as eczema at the sites where electrodes will be&#xD;
             placed&#xD;
&#xD;
          -  Hair styles hindering the placement of electrodes&#xD;
&#xD;
          -  Cranial pathologies&#xD;
&#xD;
          -  Head trauma&#xD;
&#xD;
          -  Epilepsy&#xD;
&#xD;
          -  Mental retardation&#xD;
&#xD;
          -  Any known history of neurological disorders (including epilepsy, amyotrophic lateral&#xD;
             sclerosis (ALS), multiple sclerosis (MS), stroke, cerebral palsy, any DSM-5 axis I&#xD;
             psychiatric disorder (for healthy control subjects), autism)&#xD;
&#xD;
          -  Uncorrected vision problems that would hinder cognitive testing (this also pertains to&#xD;
             subjects with color blindness in tasks where discriminating colored objects/items is&#xD;
             necessary for successful performance)&#xD;
&#xD;
          -  Pregnancy&#xD;
&#xD;
          -  Substance dependence in the past six months&#xD;
&#xD;
          -  Substance abuse in the past month&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>50 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_contact>
    <last_name>Megan A Boudewyn, Ph.D.</last_name>
    <phone>831-459-5084</phone>
    <email>mboudewyn@ucsc.edu</email>
  </overall_contact>
  <location>
    <facility>
      <name>Imaging Research Center</name>
      <address>
        <city>Sacramento</city>
        <state>California</state>
        <zip>95817</zip>
        <country>United States</country>
      </address>
    </facility>
    <status>Recruiting</status>
    <contact>
      <last_name>Minhtrang Chu, BS</last_name>
      <phone>916-734-1482</phone>
      <email>mihchu@ucdavis.edu</email>
    </contact>
    <investigator>
      <last_name>Cameron Carter, M.D.</last_name>
      <role>Principal Investigator</role>
    </investigator>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <link>
    <url>https://studypages.com/s/a-study-of-the-effects-of-brain-stimulation-on-higher-order-cognition-761403/</url>
    <description>Learn more or sign up for the study here!</description>
  </link>
  <verification_date>September 2023</verification_date>
  <study_first_submitted>January 15, 2019</study_first_submitted>
  <study_first_submitted_qc>January 18, 2019</study_first_submitted_qc>
  <study_first_posted type="Actual">January 24, 2019</study_first_posted>
  <last_update_submitted>September 14, 2023</last_update_submitted>
  <last_update_submitted_qc>September 14, 2023</last_update_submitted_qc>
  <last_update_posted type="Actual">September 18, 2023</last_update_posted>
  <responsible_party>
    <responsible_party_type>Sponsor</responsible_party_type>
  </responsible_party>
  <keyword>schizophrenia</keyword>
  <keyword>EEG</keyword>
  <keyword>tDCS</keyword>
  <keyword>dorsolateral prefrontal cortex</keyword>
  <keyword>cognitive control</keyword>
  <keyword>language</keyword>
  <keyword>transcranial direct current stimulation</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Schizophrenia</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>Yes</sharing_ipd>
    <ipd_description>Select data from this study may be submitted to the National Institute of Mental Health Data Archive (NDA). NDA is a data repository run by the National Institute of Mental Health (NIMH) that allows researchers studying mental illness to collect and share de-identified information with each other. The data repository is accessible only to qualified investigators. All subject data will be de-identified (subject names will not be used) and each subject will have a separate identifier called a Global Unique Identifier (GUID) to remove any possibility that &quot;the identities of the subjects cannot be readily ascertained or otherwise associated with the data by the repository staff or secondary data users.&quot; (45 CFR, 46.102).</ipd_description>
  </patient_data>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT03814967
org study id: 1344169
secondary id: UCD#3565
nct id: NCT03814967
lead sponsor: 
has dmc: No
is fda regulated drug: No
is fda regulated device: Yes
is unapproved device: Yes
is us export: No
The purpose of this study is to better understand the neural correlates of higher-order
      cognition, both in the healthy brain and in schizophrenia, and to determine how these
      mechanisms are modulated by transcranial direct current stimulation (tDCS) at frontal and
      occipital scalp sites. Testing the effects of tDCS at these scalp sites on cognitive task
      performance will help us understand the roles of the brain regions corresponding to these
      sites during higher-order cognitive processing (language comprehension, cognitive control,
      and related attention and memory processes). Behavioral and electrophysiological (EEG)
      measures will be used to assess cognitive performance. The investigator's overarching
      hypothesis is that stimulating prefrontal circuits with tDCS can improve cognitive control
      performance, and ultimately performance on a range of cognitive tasks, as compared to
      stimulating a different cortical region (occipital cortex) or using sham stimulation. This
      study is solely intended as basic research in order to understand brain function in healthy
      individuals and individuals with schizophrenia. This study is not intended to diagnose, cure
      or treat schizophrenia or any other disease.
allocation: Randomized
intervention model: Crossover Assignment
primary purpose: Basic Science
masking: Double (Participant, Investigator)
measure: EEG Correlates of Language and Cognitive Control
time frame: Assessment will begin immediately following stimulation and last for about 1.5 hours.
description: Electrophysiological data recorded during completion of cognitive control and language comprehension tasks. We will measure oscillatory activity in the theta, alpha, beta and gamma frequency bands.
measure: Behavioral Response (Cognitive Control Task)
time frame: Assessment will begin immediately following stimulation and last for about 1.5 hours.
description: We will assess performance on the Dot Pattern Expectancy (DPX) task (error rates and d-prime scores).
measure: Behavioral Response (Language Task)
time frame: Assessment will begin immediately following stimulation and last for about 1.5 hours.
description: We will assess performance on a novel Language Comprehension task (accuracy and semantic relatedness judgement scores).
arm group label: DLPFC Stimulation
arm group type: Experimental
description: Intervention. 20 minutes of 2 mA direct current stimulation over the dorsolateral prefrontal cortex.
arm group label: Occipital Stimulation
arm group type: Active Comparator
description: Intervention. 20 minutes of 2 mA direct current stimulation over the occipital cortex.
arm group label: Sham Stimulation
arm group type: Sham Comparator
description: Placebo Comparator. 0.5-1 minutes of 2 mA direct current stimulation over the dorsolateral prefrontal cortex followed by 19-19.5 minutes of sham stimulation
intervention type: Device
intervention name: Transcranial Direct Current Stimulation
description: In tDCS, saline-soaked electrodes are temporary affixed to the scalp and connected to a battery-powered current generator. A weak (2 mA) constant current is then briefly applied (~20 minutes) to stimulate the targeted brain area (e.g. the DLPFC). To control for placebo effects, the study will utilize a sham stimulation protocol that consists of very brief constant stimulation (~1 minute). Subjects usually cannot discern the difference between the sham and experimental stimulation protocols due to habituation.
arm group label: DLPFC Stimulation
arm group label: Occipital Stimulation
arm group label: Sham Stimulation
criteria: 
gender: All
minimum age: 18 Years
maximum age: 50 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Megan A Boudewyn, Ph.D.
phone: 831-459-5084
email: mboudewyn@ucsc.edu
facility: 
status: Recruiting
contact: 
investigator: 
country: United States
url: https://studypages.com/s/a-study-of-the-effects-of-brain-stimulation-on-higher-order-cognition-761403/
description: Learn more or sign up for the study here!
responsible party type: Sponsor
mesh term: Schizophrenia
sharing ipd: Yes
ipd description: Select data from this study may be submitted to the National Institute of Mental Health Data Archive (NDA). NDA is a data repository run by the National Institute of Mental Health (NIMH) that allows researchers studying mental illness to collect and share de-identified information with each other. The data repository is accessible only to qualified investigators. All subject data will be de-identified (subject names will not be used) and each subject will have a separate identifier called a Global Unique Identifier (GUID) to remove any possibility that "the identities of the subjects cannot be readily ascertained or otherwise associated with the data by the repository staff or secondary data users." (45 CFR, 46.102).