The Effect of Cannabidiol in Learning and Memory of Adults

Study Overview
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Brief Summary
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The main objectives of this study were to test if a singular dose of Cannabidiol (1) enhances the learning and memory of healthy human subjects, (2) test if Cannabidiol has negative effects on Retroactive and Proactive Interference during learning, (3) and test if demographic factors will influence CBD's modulation of human learning and memory.

Detailed Description
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Using a randomized, double-blind, placebo-controlled two-arm case-crossover trial, this study investigates the effect of 246 milligrams (mg) of Cannabidiol (CBD) on the learning and memory scores of human subjects, as well as the effect of Cannabidiol on Proactive and Retroactive Interference. This study also investigated the influence of demographic factors on CBD's modulation of human learning and memory. This study was conducted at Colorado State University-Pueblo (CSU Pueblo) with volunteers recruited from CSU Pueblo and the local Pueblo community. Fifty-seven subjects were randomized in a double-blind manner to receive either CBD or placebo before completing two versions of learning and memory assessments. Each version of the learning and memory assessment included the Montreal Cognitive Assessment (MOCA), the Rey Auditory Verbal Learning Task-Revised (RAVLT-R), and the Logical Memory Subject of the Weschler Memory Scale. Several components of the RAVLT-R were evaluated including the Sum of Trials (Trials I-V) score, Proactive Interference Ratio (PI Ratio), and Retroactive Interference (RI Ratio).

Official Title
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The Effect of Cannabidiol in Learning and Memory of Adults

Conditions
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Memory

Intervention / Treatment
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* Drug: Cannabidiol in Oral Dose Form
* Drug: Placebo in Oral Dose Form


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Were 18 years of age or older Exclusion Criteria: Were pregnant or breast-feeding Had been diagnosed with mental illness Didn't speak English fluently Had severe hearing problems Had recreational or opioid drug contaminants in their urine Were involved in criminal activity

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Two-arm Case-Crossover
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo (visit 1 drug administration)<br>246mg Placebo, oral, single-dose (visit 1 drug administration) | Drug: Placebo in Oral Dose Form<br>* Placebo press pills provided by Steve Goods CBD (Longmont, Colorado). Placebo pills were tested by the chemistry lab at CSU Pueblo and by Botanacar in Denver, CO. Both laboratories determined placebo pills to be pure with no heavy metals, bacteria, and pesticides detected.<br>|
| Active Comparator: Cannabidiol (visit 1 drug administration)<br>246mg Cannabidiol, oral single-dose (visit 1 drug administration) | Drug: Cannabidiol in Oral Dose Form<br>* Cannabidiol press pills provided by Steve Goods CBD (Longmont, Colorado). CBD pills were tested by the chemistry lab at CSU Pueblo and by Botanacor in Denver, CO. Both laboratories determined CBD pills to be 99.98% pure with no THC, heavy metals, bacteria, and pesticides detected.<br>* Other names: CBD;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sum of Trials (I-V) | Sum of Trials = Trial A1 + Trial A2 + Trial A3 +Trial A4 + Trial A5; Trial A1/A2/A3/A4/A5 are in reference to each trial in which list A is recalled during memory encoding; Highest score is 15 with a point awarded for each correctly recalled word from List A (15 words). | Each trial is 45 seconds for encoding and recall | 
| Proactive Interference Ratio (PI Ratio) | PI Ratio = Trial B1/A1. Proactive interference is the tendency for previously learned information to affect to hinder learning of new information. A higher proactive interference ratio indicates protective effects on memory i.e. protection from interference during learning. A lower proactive interference is indicative of negative effects on memory caused from interference. Trial A1 is in reference to list A recall during the first trial. Trial B1 is in reference to list B recall. Highest score for each trial is 15 with a point awarded for each correctly recalled word from List A (15 words) and List B (15 words). | Each trial is 45 seconds for encoding and recall | 
| Retroactive Interference Ratio (RI Ratio) | RI Ratio = Trial A6/A5. Retroactive interference is the tendency for newly learned information to hinder the memory of previously learned information. A higher retroactive interference ratio indicates protection from interference during learning. A lower retroactive interference ratio is indicative of negative effects on memory caused from interference. Trial A6 is referring to delayed recall of list A; Trial A5 is referring to the fifth trial of list A recall. Highest score for each trial is 15 with a point awarded for each word correctly recalled from List A (15 words). | Each trial is 45 seconds for encoding and recall | 
| Total Prose Recall | Total Prose Recall = Immediate Recall + Delayed Recall; Recall of a prose story was done immediately then after a delay; Highest score for prose recall test is 25 with a point awarded for each item correctly recalled in the story (25 total items). A higher recall score is indicative of better memory. | Each recall takes about 5 min for encoding and recall | 
| Montreal Cognitive Assessment Score | Assessment of basal cognitive function; Total score is 30 with a point rewarded for each correctly completed item. A higher recall score is indicative of better memory. | 10 minutes total for encoding and recall |