xml: <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/NCT05976698</url>
    </required_header>
    <id_info>
      <org_study_id>2023-00763, pk23Sterzer</org_study_id>
      <nct_id>NCT05976698</nct_id>
    </id_info>
    <brief_title>LSD-Perceptual-Choice-Study</brief_title>
    <acronym>LUCY</acronym>
    <official_title>Effects of LSD on Perceptual Decision-making in Healthy Subjects</official_title>
    <sponsors>
      <lead_sponsor>
        <agency>University Hospital, Basel, Switzerland</agency>
        <agency_class>Other</agency_class>
      </lead_sponsor>
      <collaborator>
        <agency>University of Basel</agency>
        <agency_class>Other</agency_class>
      </collaborator>
      <collaborator>
        <agency>University Psychiatric Clinics Basel</agency>
        <agency_class>Other</agency_class>
      </collaborator>
    </sponsors>
    <source>University Hospital, Basel, Switzerland</source>
    <oversight_info>
      <has_dmc>No</has_dmc>
      <is_fda_regulated_drug>No</is_fda_regulated_drug>
      <is_fda_regulated_device>No</is_fda_regulated_device>
    </oversight_info>
    <brief_summary>
      <textblock>
        The aim of the study is to characterize the effects of low doses of LSD (d-lysergic acid&#xD;
        diethylamide) on behavioral and neural indicators of feedback and feedforward signaling in&#xD;
        perceptual decision-making.&#xD;
      </textblock>
    </brief_summary>
    <detailed_description>
      <textblock>
        The study team will subject healthy participants to multiple perceptual decision-making tasks&#xD;
        after the administration of low doses of LSD (d-lysergic acid diethylamide) as a&#xD;
        pharmacological challenge. The investigators want to illuminate the behavioral and neural&#xD;
        effects of psychedelics on prior beliefs and evidence processing. Each subject will&#xD;
        participate in 3 x 5 h study sessions separated by at least 7 days. Subjects will be under&#xD;
        continuous supervision until approximately 4.5h after substance administration. The&#xD;
        participants are asked to perform the following cognitive tasks alongside EEG measurement&#xD;
        after administration of either LSD or placebo: Changepoint task, history bias task, surround&#xD;
        suppression task, auditory steady-state response paradigm, motor localizer task.&#xD;
      </textblock>
    </detailed_description>
    <overall_status>Not yet recruiting</overall_status>
    <start_date type="Anticipated">September 2023</start_date>
    <completion_date type="Anticipated">September 2024</completion_date>
    <primary_completion_date type="Anticipated">September 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>
      <intervention_model_description>Randomized, double-blinded, cross-over study</intervention_model_description>
      <primary_purpose>Basic Science</primary_purpose>
      <masking>Double (Participant, Investigator)</masking>
      <masking_description>double-blinded</masking_description>
    </study_design_info>
    <primary_outcome>
      <measure>Change in changepoint task</measure>
      <time_frame>three times (once on each of the three test days; interval between test days at least 7 days)</time_frame>
      <description>Using the changepoint task, it is examined how explicit expectations about upcoming stimuli are derived from the perceptual history and how they influence the perceptual decision in a volatile environment.&#xD;
  The study team utilizes an established computerized task and analysis pipeline including a behavioral modeling strategy based on Bayesian inference. The task requires participants to view a train of stimuli consisting of checkerboards presented on a half-circle gradient either more on the right or more on the left side of a fixation cross. Each checkerboard represents information about whether stimuli are currently more likely to appear on the right or left side of the screen. The participants have to indicate by button press, whether they believe the right or the left side is active. Task difficulty is fixed.</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Change in history bias task</measure>
      <time_frame>three times (once on each of the three test days; interval between test days at least 7 days)</time_frame>
      <description>With the history bias task, the study team investigates how implicit expectations about upcoming stimuli are derived from perceptual history and how they bias perceptual discrimination.&#xD;
  In each trial, two circular gratings will be presented concurrently on the left and right sides of a fixation cross. After complete stimulus presentation, the participants indicate by button press which of the two gratings they believe had the stronger contrast in the trial (left vs. right). Task difficulty will be adjusted individually using an online quest staircase procedure, such that participants will always perform at their 75% accuracy level.</description>
    </primary_outcome>
    <number_of_arms>6</number_of_arms>
    <enrollment type="Anticipated">30</enrollment>
    <condition>LSD Reaction</condition>
    <arm_group>
      <arm_group_label>Intervention order: 10 μg LSD - 20 μg LSD - Placebo</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
      <description>Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.&#xD;
  Order of drug administration will be 10 μg LSD - 20 μg LSD - Placebo. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+placebo; 2. visit: active+active, 3. visit: placebo+placebo.</description>
    </arm_group>
    <arm_group>
      <arm_group_label>Intervention order: 10 μg LSD - Placebo - 20 μg LSD</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
      <description>Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.&#xD;
  Order of drug administration will be 10 μg LSD - Placebo - 20 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+placebo; 2. visit: placebo+placebo, 3. visit: active+active.</description>
    </arm_group>
    <arm_group>
      <arm_group_label>Intervention order: 20 μg LSD - 10 μg LSD - Placebo</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
      <description>Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.&#xD;
  Order of drug administration will be 20 μg LSD - 10 μg LSD - Placebo. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+active; 2. visit: active+placebo, 3. visit: placebo+placebo.</description>
    </arm_group>
    <arm_group>
      <arm_group_label>Intervention order: 20 μg LSD - placebo - 10 μg LSD</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
      <description>Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.&#xD;
  Order of drug administration will be 20 μg LSD -placebo - 10 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+active; 2. visit: placebo+placebo, 3. visit: active+placebo.</description>
    </arm_group>
    <arm_group>
      <arm_group_label>Intervention order: placebo - 10 μg LSD - 20 μg LSD</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
      <description>Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.&#xD;
  Order of drug administration will be placebo - 10 μg LSD - 20 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: placebo+placebo; 2. visit: active+placebo, 3. visit: active+active.</description>
    </arm_group>
    <arm_group>
      <arm_group_label>Intervention order: placebo - 20 μg LSD - 10 μg LSD</arm_group_label>
      <arm_group_type>Experimental</arm_group_type>
      <description>Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.&#xD;
  Order of drug administration will be placebo - 20 μg LSD - 10 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: placebo+placebo; 2. visit: active+active, 3. visit: active+placebo.</description>
    </arm_group>
    <intervention>
      <intervention_type>Drug</intervention_type>
      <intervention_name>LSD 10 μg</intervention_name>
      <description>0.5 h after the start of each study session the participants will be administered 10 μg LSD per os in the form of vials containing 1ml 20% EtOH (ethanol).</description>
      <arm_group_label>Intervention order: 10 μg LSD - 20 μg LSD - Placebo</arm_group_label>
      <arm_group_label>Intervention order: 10 μg LSD - Placebo - 20 μg LSD</arm_group_label>
      <arm_group_label>Intervention order: 20 μg LSD - 10 μg LSD - Placebo</arm_group_label>
      <arm_group_label>Intervention order: 20 μg LSD - placebo - 10 μg LSD</arm_group_label>
      <arm_group_label>Intervention order: placebo - 10 μg LSD - 20 μg LSD</arm_group_label>
      <arm_group_label>Intervention order: placebo - 20 μg LSD - 10 μg LSD</arm_group_label>
    </intervention>
    <intervention>
      <intervention_type>Drug</intervention_type>
      <intervention_name>LSD 20 μg</intervention_name>
      <description>0.5 h after the start of each study session the participants will be administered 20 μg LSD per os in the form of vials containing 1ml 20% EtOH.</description>
      <arm_group_label>Intervention order: 10 μg LSD - 20 μg LSD - Placebo</arm_group_label>
      <arm_group_label>Intervention order: 10 μg LSD - Placebo - 20 μg LSD</arm_group_label>
      <arm_group_label>Intervention order: 20 μg LSD - 10 μg LSD - Placebo</arm_group_label>
      <arm_group_label>Intervention order: 20 μg LSD - placebo - 10 μg LSD</arm_group_label>
      <arm_group_label>Intervention order: placebo - 10 μg LSD - 20 μg LSD</arm_group_label>
      <arm_group_label>Intervention order: placebo - 20 μg LSD - 10 μg LSD</arm_group_label>
    </intervention>
    <intervention>
      <intervention_type>Drug</intervention_type>
      <intervention_name>Placebo</intervention_name>
      <description>0.5 h after the start of each study session the participants will be administered placebo per os in the form of vials containing 1ml 20% EtOH.</description>
      <arm_group_label>Intervention order: 10 μg LSD - 20 μg LSD - Placebo</arm_group_label>
      <arm_group_label>Intervention order: 10 μg LSD - Placebo - 20 μg LSD</arm_group_label>
      <arm_group_label>Intervention order: 20 μg LSD - 10 μg LSD - Placebo</arm_group_label>
      <arm_group_label>Intervention order: 20 μg LSD - placebo - 10 μg LSD</arm_group_label>
      <arm_group_label>Intervention order: placebo - 10 μg LSD - 20 μg LSD</arm_group_label>
      <arm_group_label>Intervention order: placebo - 20 μg LSD - 10 μg LSD</arm_group_label>
    </intervention>
    <eligibility>
      <criteria>
        <textblock>
          Inclusion Criteria:&#xD;
  &#xD;
            -  Willingness to adhere to the study protocol and sign the consent form&#xD;
  &#xD;
            -  ≥ 18 and ≤ 65 years of age at Screening&#xD;
  &#xD;
            -  Body mass index 18-29&#xD;
  &#xD;
            -  Fluent understanding of German&#xD;
  &#xD;
            -  Normal or corrected-to-normal vision&#xD;
  &#xD;
            -  Willingness to not operate a traffic vehicle or heavy machinery 24 hours after&#xD;
               substance administration&#xD;
  &#xD;
            -  Willingness to refrain from taking illicit psychoactive substances, including&#xD;
               cannabis, for the duration of the study&#xD;
  &#xD;
            -  Willingness to not consume more than one alcoholic standard drink the night before the&#xD;
               study sessions and not consume alcohol for 24 h after each study session&#xD;
  &#xD;
            -  Willingness to abstain from xanthine-based liquids from the evenings prior to the&#xD;
               study sessions and during the sessions&#xD;
  &#xD;
            -  Willingness to use effective birth-control throughout the study duration&#xD;
  &#xD;
            -  Adequate task performance in the decision-making tasks during a practice session in&#xD;
               the screening visit&#xD;
  &#xD;
          Exclusion Criteria:&#xD;
  &#xD;
            -  Recent (&lt;30 days) or current participation in another clinical trial&#xD;
  &#xD;
            -  Women that are pregnant, nursing, or planning to become pregnant during the study&#xD;
               period&#xD;
  &#xD;
            -  Current use of contraindicated/psychoactive medications or illicit drugs&#xD;
  &#xD;
            -  Lifetime use of classical psychedelics more than 20 times, or any time within the&#xD;
               previous two months&#xD;
  &#xD;
            -  Consumption of &gt;5 cigarettes per day or &gt;20 alcoholic standard drinks per week&#xD;
  &#xD;
            -  Severe chronic or acute medical condition&#xD;
  &#xD;
            -  Hypertension (&gt;140/90 mmHg) or hypotension (&lt;85mmHg systolic)&#xD;
  &#xD;
            -  Current or lifetime major mental health disorder&#xD;
  &#xD;
            -  Personal or family (first-degree) history of a primary psychotic disorder&#xD;
        </textblock>
      </criteria>
      <gender>All</gender>
      <minimum_age>18 Years</minimum_age>
      <maximum_age>65 Years</maximum_age>
      <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
    </eligibility>
    <overall_official>
      <last_name>Philipp Sterzer, Prof. Dr.</last_name>
      <role>Principal Investigator</role>
      <affiliation>University Psychiatric Clinics Basel</affiliation>
    </overall_official>
    <overall_contact>
      <last_name>Philipp Sterzer, Prof. Dr.</last_name>
      <phone>+41 61 325 81 55</phone>
      <email>philipp.sterzer@upk.ch</email>
    </overall_contact>
    <overall_contact_backup>
      <last_name>Lucca Jaeckel</last_name>
      <phone>+41 61 325 81 51</phone>
      <email>lucca.jaeckel@unibas.ch</email>
    </overall_contact_backup>
    <location>
      <facility>
        <name>University Psychiatric Clinics Basel</name>
        <address>
          <city>Basel</city>
          <zip>4002</zip>
          <country>Switzerland</country>
        </address>
      </facility>
      <contact>
        <last_name>Philipp Sterzer, Prof.Dr.</last_name>
        <phone>+41 61 325 81 55</phone>
        <email>philipp.sterzer@upk.ch</email>
      </contact>
      <contact_backup>
        <last_name>Lucca Jaeckel</last_name>
        <phone>+41 61 325 8151</phone>
        <email>Lucca.Jaeckel@unibas.ch</email>
      </contact_backup>
      <investigator>
        <last_name>Philipp Sterzer, Prof. Dr.</last_name>
        <role>Principal Investigator</role>
      </investigator>
    </location>
    <location_countries>
      <country>Switzerland</country>
    </location_countries>
    <verification_date>July 2023</verification_date>
    <study_first_submitted>July 24, 2023</study_first_submitted>
    <study_first_submitted_qc>July 27, 2023</study_first_submitted_qc>
    <study_first_posted type="Actual">August 4, 2023</study_first_posted>
    <last_update_submitted>July 27, 2023</last_update_submitted>
    <last_update_submitted_qc>July 27, 2023</last_update_submitted_qc>
    <last_update_posted type="Actual">August 4, 2023</last_update_posted>
    <responsible_party>
      <responsible_party_type>Sponsor</responsible_party_type>
    </responsible_party>
    <keyword>neural and behavioral indicators</keyword>
    <keyword>serotonergic system</keyword>
    <keyword>perceptual decision-making</keyword>
    <intervention_browse>
      <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
      <mesh_term>Lysergic Acid Diethylamide</mesh_term>
    </intervention_browse>
    <!-- Results have not yet been posted for this study                                          -->
  </clinical_study>
  
  
text: 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/NCT05976698
  org study id: 2023-00763, pk23Sterzer
  nct id: NCT05976698
  lead sponsor: 
  collaborator: 
  collaborator: 
  has dmc: No
  is fda regulated drug: No
  is fda regulated device: No
  The aim of the study is to characterize the effects of low doses of LSD (d-lysergic acid
        diethylamide) on behavioral and neural indicators of feedback and feedforward signaling in
        perceptual decision-making.
  The study team will subject healthy participants to multiple perceptual decision-making tasks
        after the administration of low doses of LSD (d-lysergic acid diethylamide) as a
        pharmacological challenge. The investigators want to illuminate the behavioral and neural
        effects of psychedelics on prior beliefs and evidence processing. Each subject will
        participate in 3 x 5 h study sessions separated by at least 7 days. Subjects will be under
        continuous supervision until approximately 4.5h after substance administration. The
        participants are asked to perform the following cognitive tasks alongside EEG measurement
        after administration of either LSD or placebo: Changepoint task, history bias task, surround
        suppression task, auditory steady-state response paradigm, motor localizer task.
  allocation: Randomized
  intervention model: Crossover Assignment
  intervention model description: Randomized, double-blinded, cross-over study
  primary purpose: Basic Science
  masking: Double (Participant, Investigator)
  masking description: double-blinded
  measure: Change in changepoint task
  time frame: three times (once on each of the three test days; interval between test days at least 7 days)
  description: Using the changepoint task, it is examined how explicit expectations about upcoming stimuli are derived from the perceptual history and how they influence the perceptual decision in a volatile environment.
  The study team utilizes an established computerized task and analysis pipeline including a behavioral modeling strategy based on Bayesian inference. The task requires participants to view a train of stimuli consisting of checkerboards presented on a half-circle gradient either more on the right or more on the left side of a fixation cross. Each checkerboard represents information about whether stimuli are currently more likely to appear on the right or left side of the screen. The participants have to indicate by button press, whether they believe the right or the left side is active. Task difficulty is fixed.
  measure: Change in history bias task
  time frame: three times (once on each of the three test days; interval between test days at least 7 days)
  description: With the history bias task, the study team investigates how implicit expectations about upcoming stimuli are derived from perceptual history and how they bias perceptual discrimination.
  In each trial, two circular gratings will be presented concurrently on the left and right sides of a fixation cross. After complete stimulus presentation, the participants indicate by button press which of the two gratings they believe had the stronger contrast in the trial (left vs. right). Task difficulty will be adjusted individually using an online quest staircase procedure, such that participants will always perform at their 75% accuracy level.
  arm group label: Intervention order: 10 μg LSD - 20 μg LSD - Placebo
  arm group type: Experimental
  description: Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.
  Order of drug administration will be 10 μg LSD - 20 μg LSD - Placebo. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+placebo; 2. visit: active+active, 3. visit: placebo+placebo.
  arm group label: Intervention order: 10 μg LSD - Placebo - 20 μg LSD
  arm group type: Experimental
  description: Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.
  Order of drug administration will be 10 μg LSD - Placebo - 20 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+placebo; 2. visit: placebo+placebo, 3. visit: active+active.
  arm group label: Intervention order: 20 μg LSD - 10 μg LSD - Placebo
  arm group type: Experimental
  description: Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.
  Order of drug administration will be 20 μg LSD - 10 μg LSD - Placebo. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+active; 2. visit: active+placebo, 3. visit: placebo+placebo.
  arm group label: Intervention order: 20 μg LSD - placebo - 10 μg LSD
  arm group type: Experimental
  description: Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.
  Order of drug administration will be 20 μg LSD -placebo - 10 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: active+active; 2. visit: placebo+placebo, 3. visit: active+placebo.
  arm group label: Intervention order: placebo - 10 μg LSD - 20 μg LSD
  arm group type: Experimental
  description: Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.
  Order of drug administration will be placebo - 10 μg LSD - 20 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: placebo+placebo; 2. visit: active+placebo, 3. visit: active+active.
  arm group label: Intervention order: placebo - 20 μg LSD - 10 μg LSD
  arm group type: Experimental
  description: Each subject will participate in 3 x 5 h study sessions separated by at least 7 days.
  Order of drug administration will be placebo - 20 μg LSD - 10 μg LSD. Vials will contain either 10μg (Active) or 0 μg LSD (Placebo). Thus, participants will be administered two vials on each study visit. 1. visit: placebo+placebo; 2. visit: active+active, 3. visit: active+placebo.
  intervention type: Drug
  intervention name: LSD 10 μg
  description: 0.5 h after the start of each study session the participants will be administered 10 μg LSD per os in the form of vials containing 1ml 20% EtOH (ethanol).
  arm group label: Intervention order: 10 μg LSD - 20 μg LSD - Placebo
  arm group label: Intervention order: 10 μg LSD - Placebo - 20 μg LSD
  arm group label: Intervention order: 20 μg LSD - 10 μg LSD - Placebo
  arm group label: Intervention order: 20 μg LSD - placebo - 10 μg LSD
  arm group label: Intervention order: placebo - 10 μg LSD - 20 μg LSD
  arm group label: Intervention order: placebo - 20 μg LSD - 10 μg LSD
  intervention type: Drug
  intervention name: LSD 20 μg
  description: 0.5 h after the start of each study session the participants will be administered 20 μg LSD per os in the form of vials containing 1ml 20% EtOH.
  arm group label: Intervention order: 10 μg LSD - 20 μg LSD - Placebo
  arm group label: Intervention order: 10 μg LSD - Placebo - 20 μg LSD
  arm group label: Intervention order: 20 μg LSD - 10 μg LSD - Placebo
  arm group label: Intervention order: 20 μg LSD - placebo - 10 μg LSD
  arm group label: Intervention order: placebo - 10 μg LSD - 20 μg LSD
  arm group label: Intervention order: placebo - 20 μg LSD - 10 μg LSD
  intervention type: Drug
  intervention name: Placebo
  description: 0.5 h after the start of each study session the participants will be administered placebo per os in the form of vials containing 1ml 20% EtOH.
  arm group label: Intervention order: 10 μg LSD - 20 μg LSD - Placebo
  arm group label: Intervention order: 10 μg LSD - Placebo - 20 μg LSD
  arm group label: Intervention order: 20 μg LSD - 10 μg LSD - Placebo
  arm group label: Intervention order: 20 μg LSD - placebo - 10 μg LSD
  arm group label: Intervention order: placebo - 10 μg LSD - 20 μg LSD
  arm group label: Intervention order: placebo - 20 μg LSD - 10 μg LSD
  criteria: 
  gender: All
  minimum age: 18 Years
  maximum age: 65 Years
  healthy volunteers: Accepts Healthy Volunteers
  last name: Philipp Sterzer, Prof. Dr.
  role: Principal Investigator
  affiliation: University Psychiatric Clinics Basel
  last name: Philipp Sterzer, Prof. Dr.
  phone: +41 61 325 81 55
  email: philipp.sterzer@upk.ch
  last name: Lucca Jaeckel
  phone: +41 61 325 81 51
  email: lucca.jaeckel@unibas.ch
  facility: 
  contact: 
  contact backup: 
  investigator: 
  country: Switzerland
  responsible party type: Sponsor
  mesh term: Lysergic Acid Diethylamide