Electrophysiological Study of the Functioning of Magnocellular Visual Pathway in Regular Cannabis Users
Not Applicable
Completed
- Conditions
- Cannabis Use
- Interventions
- Other: ElectroretinographyOther: Contrast sensitivity test during ElectroencephalographyOther: Visual simultaneity test during ElectroencephalographyOther: Face perception test during ElectroencephalographyOther: Delayed Matching to Sample (DMS) testOther: CAST (cannabis abuse screening test)Other: PANSS (Positive And Negative Symptoms Scale) testOther: Rapid Visual Information Processing (RVP) testOther: Spatial Working Memory (SWM) testOther: Test for attentional performance (TAP) / Divided AttentionOther: Collection of saliva sample
- Registration Number
- NCT02864680
- Lead Sponsor
- 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).
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 163
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
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Healthy volunteers, not cannabis/tobacco users Rapid Visual Information Processing (RVP) test - Healthy volunteers, tobacco users Delayed Matching to Sample (DMS) test - Healthy volunteers, tobacco users Rapid Visual Information Processing (RVP) test - Schizophrenia patients CAST (cannabis abuse screening test) - Schizophrenia patients Test for attentional performance (TAP) / Divided Attention - Schizophrenia patients Collection of saliva sample - Healthy volunteers, tobacco users Test for attentional performance (TAP) / Divided Attention - Cannabis users Electroretinography - Cannabis users Rapid Visual Information Processing (RVP) test - Cannabis users Collection of saliva sample - Schizophrenia patients Electroretinography - Schizophrenia patients Visual simultaneity test during Electroencephalography - Schizophrenia patients Delayed Matching to Sample (DMS) test - Cannabis users Contrast sensitivity test during Electroencephalography - Cannabis users CAST (cannabis abuse screening test) - Cannabis users Spatial Working Memory (SWM) test - Cannabis users Visual simultaneity test during Electroencephalography - Cannabis users Test for attentional performance (TAP) / Divided Attention - Healthy volunteers, not cannabis/tobacco users Delayed Matching to Sample (DMS) test - Healthy volunteers, not cannabis/tobacco users Spatial Working Memory (SWM) test - Healthy volunteers, not cannabis/tobacco users Test for attentional performance (TAP) / Divided Attention - Healthy volunteers, not cannabis/tobacco users Collection of saliva sample - Healthy volunteers, tobacco users Visual simultaneity test during Electroencephalography - Healthy volunteers, tobacco users Spatial Working Memory (SWM) test - Schizophrenia patients Spatial Working Memory (SWM) test - Schizophrenia patients Contrast sensitivity test during Electroencephalography - Cannabis users Face perception test during Electroencephalography - Cannabis users Delayed Matching to Sample (DMS) test - Healthy volunteers, not cannabis/tobacco users Electroretinography - Healthy volunteers, not cannabis/tobacco users Face perception test during Electroencephalography - Healthy volunteers, tobacco users Electroretinography - Healthy volunteers, tobacco users Contrast sensitivity test during Electroencephalography - Healthy volunteers, tobacco users Face perception test during Electroencephalography - Healthy volunteers, not cannabis/tobacco users Contrast sensitivity test during Electroencephalography - Healthy volunteers, not cannabis/tobacco users Visual simultaneity test during Electroencephalography - Healthy volunteers, tobacco users Collection of saliva sample - Schizophrenia patients Face perception test during Electroencephalography - Schizophrenia patients PANSS (Positive And Negative Symptoms Scale) test - Schizophrenia patients Rapid Visual Information Processing (RVP) test -
- Primary Outcome Measures
Name Time Method Culmination time of the P100 wave in contrast sensibility test up to 1 month Amplitude of P100 wave in contrast sensibility test up to 1 month
- Secondary Outcome Measures
Name Time Method Amplitude of P100 wave in visual simultaneity test up to 1 month Culmination time of P100 wave in visual simultaneity test up to 1 month Culmination time of P100 wave in face perception test up to 1 month Culmination time of "a" wave in different ERG sequences day 0 Amplitude of P100 wave in face perception test up to 1 month Amplitude of N170 wave in face perception test up to 1 month Amplitude of "b" wave in different ERG sequences day 0 Culmination time of "b" wave in different ERG sequences day 0 Culmination time of N170 wave in face perception test up to 1 month Amplitude of "a" wave in different ERG sequences day 0
Trial Locations
- Locations (1)
Maison des Addictions - CHU de Nancy, Hôpital St Julien
🇫🇷Nancy, France