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Electrophysiological Study of the Functioning of Magnocellular Visual Pathway in Regular Cannabis Users (CAUSA MAP)

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ClinicalTrials.gov Identifier: NCT02864680
Recruitment Status : Recruiting
First Posted : August 12, 2016
Last Update Posted : May 13, 2019
Sponsor:
Information provided by (Responsible Party):
Central Hospital, Nancy, France

Brief Summary:

This study will evaluate the impact of regular use of cannabis on the spatial sensitivity of magnocellular system (visual event-related potential, visual ERP).

Secondary purposes of this study are to evaluate the impact of regular use of cannabis on the temporal sensitivity of magnocellular system (visual event-related potential), on the dynamics of cortical visual processing during face perception test (visual event-related potential) and on functioning of retinal photopic and scotopic systems (electroretinogram).

The ancillary study is a genetic analysis of a group of candidate genes that aims to identify biomarkers for changes in visual processing. This will allow to distinguish among more homogeneous and specific groups in future studies on larger cannabis user population. This ancillary study concerns all participants subject to their informed consent (facultative study).


Condition or disease Intervention/treatment Phase
Cannabis Use Other: Electroretinography Other: Contrast sensitivity test during Electroencephalography Other: Visual simultaneity test during Electroencephalography Other: Face perception test during Electroencephalography Other: CAST (cannabis abuse screening test) Other: PANSS (Positive And Negative Symptoms Scale) test Other: Delayed Matching to Sample (DMS) test Other: Spatial Working Memory (SWM) test Other: Rapid Visual Information Processing (RVP) test Other: Test for attentional performance (TAP) / Divided Attention Other: Collection of saliva sample Not Applicable

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 190 participants
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Other
Official Title: Electrophysiological Study of the Functioning of Magnocellular Visual Pathway in Regular Cannabis Users
Actual Study Start Date : February 2014
Estimated Primary Completion Date : July 2019
Estimated Study Completion Date : July 2019

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Marijuana

Arm Intervention/treatment
Cannabis users Other: Electroretinography
Other: Contrast sensitivity test during Electroencephalography
Stimuli are black and white grids, having different range of spatial frequencies, presented with different contrasts on a grey background thanks to a computer monitor, in a dark room. Participants are requested to maintain central fixation. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: Visual simultaneity test during Electroencephalography
Two vertical bars are showed on a monitor, on the link and right of point of central fixation. Bars appear simultaneously or with a 10 to 200 ms asynchrony. Participants must determine whether stimuli are simultaneous or asynchronous and answer pressing the link button for simultaneity or right button for asynchrony. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: Face perception test during Electroencephalography
Faces filtered in different spatial frequence ranges are showed randomly on a monitor, in a dark room. Participants must maintain a central fixation thank to a fixation cross. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: CAST (cannabis abuse screening test)
Other: Delayed Matching to Sample (DMS) test
Other: Spatial Working Memory (SWM) test
Other: Rapid Visual Information Processing (RVP) test
Other: Test for attentional performance (TAP) / Divided Attention
Other: Collection of saliva sample
In case of specific consent of participant to ancillary study, for ancillary study

Healthy volunteers, not cannabis/tobacco users Other: Electroretinography
Other: Contrast sensitivity test during Electroencephalography
Stimuli are black and white grids, having different range of spatial frequencies, presented with different contrasts on a grey background thanks to a computer monitor, in a dark room. Participants are requested to maintain central fixation. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: Visual simultaneity test during Electroencephalography
Two vertical bars are showed on a monitor, on the link and right of point of central fixation. Bars appear simultaneously or with a 10 to 200 ms asynchrony. Participants must determine whether stimuli are simultaneous or asynchronous and answer pressing the link button for simultaneity or right button for asynchrony. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: Face perception test during Electroencephalography
Faces filtered in different spatial frequence ranges are showed randomly on a monitor, in a dark room. Participants must maintain a central fixation thank to a fixation cross. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: Delayed Matching to Sample (DMS) test
Other: Spatial Working Memory (SWM) test
Other: Rapid Visual Information Processing (RVP) test
Other: Test for attentional performance (TAP) / Divided Attention
Other: Collection of saliva sample
In case of specific consent of participant to ancillary study, for ancillary study

Healthy volunteers, tobacco users Other: Electroretinography
Other: Contrast sensitivity test during Electroencephalography
Stimuli are black and white grids, having different range of spatial frequencies, presented with different contrasts on a grey background thanks to a computer monitor, in a dark room. Participants are requested to maintain central fixation. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: Visual simultaneity test during Electroencephalography
Two vertical bars are showed on a monitor, on the link and right of point of central fixation. Bars appear simultaneously or with a 10 to 200 ms asynchrony. Participants must determine whether stimuli are simultaneous or asynchronous and answer pressing the link button for simultaneity or right button for asynchrony. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: Face perception test during Electroencephalography
Faces filtered in different spatial frequence ranges are showed randomly on a monitor, in a dark room. Participants must maintain a central fixation thank to a fixation cross. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: Delayed Matching to Sample (DMS) test
Other: Spatial Working Memory (SWM) test
Other: Rapid Visual Information Processing (RVP) test
Other: Test for attentional performance (TAP) / Divided Attention
Other: Collection of saliva sample
In case of specific consent of participant to ancillary study, for ancillary study

Schizophrenia patients Other: Electroretinography
Other: Contrast sensitivity test during Electroencephalography
Stimuli are black and white grids, having different range of spatial frequencies, presented with different contrasts on a grey background thanks to a computer monitor, in a dark room. Participants are requested to maintain central fixation. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: Visual simultaneity test during Electroencephalography
Two vertical bars are showed on a monitor, on the link and right of point of central fixation. Bars appear simultaneously or with a 10 to 200 ms asynchrony. Participants must determine whether stimuli are simultaneous or asynchronous and answer pressing the link button for simultaneity or right button for asynchrony. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: Face perception test during Electroencephalography
Faces filtered in different spatial frequence ranges are showed randomly on a monitor, in a dark room. Participants must maintain a central fixation thank to a fixation cross. During the test patients stay sit, head hold by chin strap. A pause can be asked by participant and done at every moment. This test lasts approximately 30 minutes.

Other: CAST (cannabis abuse screening test)
Other: PANSS (Positive And Negative Symptoms Scale) test
Other: Delayed Matching to Sample (DMS) test
Other: Spatial Working Memory (SWM) test
Other: Rapid Visual Information Processing (RVP) test
Other: Test for attentional performance (TAP) / Divided Attention
Other: Collection of saliva sample
In case of specific consent of participant to ancillary study, for ancillary study




Primary Outcome Measures :
  1. Amplitude of P100 wave in contrast sensibility test [ Time Frame: up to 1 month ]
  2. Culmination time of the P100 wave in contrast sensibility test [ Time Frame: up to 1 month ]

Secondary Outcome Measures :
  1. Amplitude of P100 wave in visual simultaneity test [ Time Frame: up to 1 month ]
  2. Culmination time of P100 wave in visual simultaneity test [ Time Frame: up to 1 month ]
  3. Amplitude of P100 wave in face perception test [ Time Frame: up to 1 month ]
  4. Amplitude of N170 wave in face perception test [ Time Frame: up to 1 month ]
  5. Culmination time of P100 wave in face perception test [ Time Frame: up to 1 month ]
  6. Culmination time of N170 wave in face perception test [ Time Frame: up to 1 month ]
  7. Amplitude of "a" wave in different ERG sequences [ Time Frame: day 0 ]
  8. Amplitude of "b" wave in different ERG sequences [ Time Frame: day 0 ]
  9. Culmination time of "a" wave in different ERG sequences [ Time Frame: day 0 ]
  10. Culmination time of "b" wave in different ERG sequences [ Time Frame: day 0 ]

Other Outcome Measures:
  1. Relationship between variants of candidate genes for alterations of visual treatment and amplitude of P100 wave in contrast sensibility test [ Time Frame: up to 3 years ]


Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


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Ages Eligible for Study:   18 Years to 55 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Affiliation to social security plan
  • Normal visual acuity or adjusted to normal and normal dilated fundus examination
  • Signature of informed consent
  • Cannabis user group: More than 7 cannabis uses per week during the previous month
  • Cannabis user group: Positive urinary analysis for presence of cannabis
  • Healthy, non user control group: Absence of cannabis and tobacco use during last 12 months
  • Healthy, non user control group: Negative urinary analysis for presence of cannabis
  • Healthy, non user control group: Age and sex matching with cannabis user group
  • Healthy, tobacco user control group: Tobacco use from at least 12 months
  • Healthy, tobacco user control group: Low to very strong addiction to tobacco (Fagerström test)
  • Healthy, tobacco user control group: Absence of cannabis use from more than 12 months
  • Healthy, tobacco user control group: Negative urinary analysis for presence of cannabis
  • Healthy, tobacco user control group:Age and sex matching with cannabis user group
  • Schizophrenia patient control group: Schizophrenia according to DMS IV criteria (MINI test)
  • Schizophrenia patient control group: Absence of cannabis use from more than one month (regardless of tobacco use)
  • Schizophrenia patient control group: Negative urinary analysis for presence of cannabis
  • Schizophrenia patient control group: Age and sex matching with cannabis user group

Exclusion Criteria:

  • Acute psychiatric pathology (axis I of DSM IV, measured by MINI) except anxiety disorder (except schizophrenia group)
  • Deficiency of the subject making difficult or impossible his/her participation to the study or the comprehension of the information
  • Dyslexia
  • Addiction to alcohol according to AUDIT scale
  • Abuse or addiction to other substances according to DSM IV criteria
  • Acute retinal disorder
  • Chronic glaucoma
  • Ophthalmic pathology affecting visual acuity
  • Current ocular infection
  • Persons under guardianship, curatorship or judicial protection
  • Pregnant or breast-feeding women
  • Persons with life-and-death emergency
  • Absence of social security plan
  • Results of preliminary medical examinations incompatible with the study
  • Simultaneous participation to another therapeutic interventional study

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02864680


Contacts
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Contact: Vincent LAPREVOTE v.laprevote@chu-nancy.fr

Locations
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France
Maison des Addictions - CHU de Nancy, Hôpital St Julien Recruiting
Nancy, France
Sponsors and Collaborators
Central Hospital, Nancy, France
Investigators
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Principal Investigator: Vincent LAPREVOTE Maison des Addictions - CHU de Nancy, France

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Responsible Party: Central Hospital, Nancy, France
ClinicalTrials.gov Identifier: NCT02864680     History of Changes
Other Study ID Numbers: 2013-A00097-38
First Posted: August 12, 2016    Key Record Dates
Last Update Posted: May 13, 2019
Last Verified: June 2018
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Keywords provided by Central Hospital, Nancy, France:
cannabis
magnocellular pathway
Additional relevant MeSH terms:
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Marijuana Abuse
Substance-Related Disorders
Chemically-Induced Disorders
Mental Disorders