<clinical_study>
  <!-- This xml conforms to an XML Schema at:
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  <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/NCT02979314</url>
  </required_header>
  <id_info>
    <org_study_id>2016-00464</org_study_id>
    <nct_id>NCT02979314</nct_id>
  </id_info>
  <brief_title>The Influence of GVS on Mental Transformation</brief_title>
  <official_title>Overlapping Cortical Networks of Illusory and Mental Body Transformations</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>University of Zurich</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>University of Zurich</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      Corroboratory behavioral evidence showed interaction effects between vestibular stimulation&#xD;
      and egocentric transformation.&#xD;
&#xD;
      The investigators here examine in healthy participants, whether there are shared brain&#xD;
      mechanisms underlying galvanic vestibular stimulation, illusory self-motion and egocentric&#xD;
      transformation, as well as their interaction.&#xD;
&#xD;
      It is hypothesized that the GVS induced illusory self-motion dampens the ability to perform&#xD;
      egocentric mental transformation.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Theories of embodied mental rotation suggest overlapping processes between real body and&#xD;
      egocentric mental transformations. Corroboratory behavioral evidence showed interaction&#xD;
      effects between vestibular stimulation and egocentric transformation. Yet, no study so far&#xD;
      has investigated which cortical areas are involved in vestibular processing and/or illusory&#xD;
      self-motion and mental transformation tasks within the same participants. This however seems&#xD;
      crucial, as important individual differences exist for both mental transformation abilities&#xD;
      as well as in subjective perception of artificial vestibular stimulation.&#xD;
&#xD;
      The primary objective is to reveal which brain area(s) are involved in the interaction of&#xD;
      illusory self-motion (as induced by galvanic vestibular stimulation (GVS)) and egocentric&#xD;
      mental transformation, as compared to no illusory self-motion or object-based mental&#xD;
      transformation. It is hypothesized that the GVS induced illusory self-motion dampens the&#xD;
      ability to perform egocentric mental transformation more than object-based mental&#xD;
      transformation.&#xD;
&#xD;
      As previous behavioral studies on such an interaction were always done in a sitting position,&#xD;
      a secondary objective is to first replicate previous behavioral mental rotation studies that&#xD;
      used GVS, in the Magnetic Resonance (MR) -scanner comparable setting. Moreover, as no brain&#xD;
      imaging study so far has investigated subjective illusory motion experience induced by GVS,&#xD;
      illusory self-motion will be measured and included in the statistical model to find specific&#xD;
      brain regions modulating the illusory self-motion perception.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date type="Actual">December 1, 2016</start_date>
  <completion_date type="Actual">May 26, 2017</completion_date>
  <primary_completion_date type="Actual">May 26, 2017</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>N/A</allocation>
    <intervention_model>Single Group Assignment</intervention_model>
    <primary_purpose>Basic Science</primary_purpose>
    <masking>None (Open Label)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Blood Oxygen-Level Dependent (BOLD) -signal change in response to egocentric mental transformation</measure>
    <time_frame>one day</time_frame>
    <description>The Relative BOLD-signal change in response to egocentric mental transformation during GVS versus mental transformation during sham stimulation will be measured in an functional Magnetic Resonance Imaging (fMRI) paradigm</description>
  </primary_outcome>
  <number_of_arms>1</number_of_arms>
  <enrollment type="Actual">32</enrollment>
  <condition>Focus of Study: Higher Cognition and the Vestibular System</condition>
  <arm_group>
    <arm_group_label>Galvanic Vestibular Stimulation</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>A standard placement of the electrodes will be used for GVS and sham, placed on the mastoids. Weak currents up to maximally 3 mA will be used (tested before in each participant individually, and expected mean current will be around 1.5 mA). Previous studies have used Magnetic Resonance (MR) compatible GVS without reporting any discomfort for the participants, however weak sensations of nausea could be possible and in case that they are disturbing for the participants the experiment will be aborted. Continuous stimulation for up to 30min with intensities of 1-1.5 mA is generally considered as safe and free of any considerable side effects.</description>
  </arm_group>
  <intervention>
    <intervention_type>Device</intervention_type>
    <intervention_name>Galvanic Vestibular Stimulation</intervention_name>
    <description>The investigators aim to study the influence of Galvanic Vestibular Stimulation on the brain mechanisms underlying illusory self-motion and its influence on egocentric mental transformation. As a control condition sham stimulation will be applied by the same device within the same participants in different trials. Participants should not note the difference.</description>
    <arm_group_label>Galvanic Vestibular Stimulation</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Male&#xD;
&#xD;
          -  Written informed consent by the participant&#xD;
&#xD;
          -  Right handed&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  possession of metallic implants, cardiac pacemakers, neuro-stimulators, metal splinter&#xD;
             injuries&#xD;
&#xD;
          -  claustrophobia&#xD;
&#xD;
          -  no ability to lie still in the scanner, e.g. a cold leading to frequent sneezing and&#xD;
             subsequent head movements&#xD;
&#xD;
          -  history of neurological or psychiatric disorder&#xD;
&#xD;
          -  hearing problems&#xD;
&#xD;
          -  concomitant medication&#xD;
&#xD;
          -  strong motion sensitivity&#xD;
&#xD;
          -  vestibular deficits&#xD;
      </textblock>
    </criteria>
    <gender>Male</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>55 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Lars Michels, MD</last_name>
    <role>Principal Investigator</role>
    <affiliation>University Hospital Zurich, Div. of Neuroradiology</affiliation>
  </overall_official>
  <verification_date>October 2018</verification_date>
  <study_first_submitted>August 23, 2016</study_first_submitted>
  <study_first_submitted_qc>November 28, 2016</study_first_submitted_qc>
  <study_first_posted type="Estimate">December 1, 2016</study_first_posted>
  <last_update_submitted>October 29, 2018</last_update_submitted>
  <last_update_submitted_qc>October 29, 2018</last_update_submitted_qc>
  <last_update_posted type="Actual">October 31, 2018</last_update_posted>
  <responsible_party>
    <responsible_party_type>Sponsor</responsible_party_type>
  </responsible_party>
  <patient_data>
    <sharing_ipd>Undecided</sharing_ipd>
  </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/NCT02979314
org study id: 2016-00464
nct id: NCT02979314
lead sponsor: 
has dmc: No
Corroboratory behavioral evidence showed interaction effects between vestibular stimulation
      and egocentric transformation.

      The investigators here examine in healthy participants, whether there are shared brain
      mechanisms underlying galvanic vestibular stimulation, illusory self-motion and egocentric
      transformation, as well as their interaction.

      It is hypothesized that the GVS induced illusory self-motion dampens the ability to perform
      egocentric mental transformation.
Theories of embodied mental rotation suggest overlapping processes between real body and
      egocentric mental transformations. Corroboratory behavioral evidence showed interaction
      effects between vestibular stimulation and egocentric transformation. Yet, no study so far
      has investigated which cortical areas are involved in vestibular processing and/or illusory
      self-motion and mental transformation tasks within the same participants. This however seems
      crucial, as important individual differences exist for both mental transformation abilities
      as well as in subjective perception of artificial vestibular stimulation.

      The primary objective is to reveal which brain area(s) are involved in the interaction of
      illusory self-motion (as induced by galvanic vestibular stimulation (GVS)) and egocentric
      mental transformation, as compared to no illusory self-motion or object-based mental
      transformation. It is hypothesized that the GVS induced illusory self-motion dampens the
      ability to perform egocentric mental transformation more than object-based mental
      transformation.

      As previous behavioral studies on such an interaction were always done in a sitting position,
      a secondary objective is to first replicate previous behavioral mental rotation studies that
      used GVS, in the Magnetic Resonance (MR) -scanner comparable setting. Moreover, as no brain
      imaging study so far has investigated subjective illusory motion experience induced by GVS,
      illusory self-motion will be measured and included in the statistical model to find specific
      brain regions modulating the illusory self-motion perception.
allocation: N/A
intervention model: Single Group Assignment
primary purpose: Basic Science
masking: None (Open Label)
measure: Blood Oxygen-Level Dependent (BOLD) -signal change in response to egocentric mental transformation
time frame: one day
description: The Relative BOLD-signal change in response to egocentric mental transformation during GVS versus mental transformation during sham stimulation will be measured in an functional Magnetic Resonance Imaging (fMRI) paradigm
arm group label: Galvanic Vestibular Stimulation
arm group type: Experimental
description: A standard placement of the electrodes will be used for GVS and sham, placed on the mastoids. Weak currents up to maximally 3 mA will be used (tested before in each participant individually, and expected mean current will be around 1.5 mA). Previous studies have used Magnetic Resonance (MR) compatible GVS without reporting any discomfort for the participants, however weak sensations of nausea could be possible and in case that they are disturbing for the participants the experiment will be aborted. Continuous stimulation for up to 30min with intensities of 1-1.5 mA is generally considered as safe and free of any considerable side effects.
intervention type: Device
intervention name: Galvanic Vestibular Stimulation
description: The investigators aim to study the influence of Galvanic Vestibular Stimulation on the brain mechanisms underlying illusory self-motion and its influence on egocentric mental transformation. As a control condition sham stimulation will be applied by the same device within the same participants in different trials. Participants should not note the difference.
arm group label: Galvanic Vestibular Stimulation
criteria: 
gender: Male
minimum age: 18 Years
maximum age: 55 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Lars Michels, MD
role: Principal Investigator
affiliation: University Hospital Zurich, Div. of Neuroradiology
responsible party type: Sponsor
sharing ipd: Undecided