Effects of THC and CBD on Human Episodic Memory Function

Study Overview
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Brief Summary
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THC and CBD have distinct symptomatic and behavioral effects. In healthy individuals, THC can induce psychotic symptoms and anxiety, and can impair memory. In contrast, CBD has anxiolytic and possibly antipsychotic properties, while not impairing memory and other cognitive functions. Instead, CBD has been shown to have significant neuroprotective effects. In humans, CBD values correlated positively with gray matter concentration in bilateral hippocampus. Recent data from experimental animals and in vitro studies suggest that these distinct effects might be caused by opposing effects on brain cannabinoid receptors. Neuroimaging studies have consistently identified brain activity recorded at prefrontal and medial temporal regions as relevant for episodic memory. Additionally, the abundance of cannabinoid receptors in the hippocampus and the parahippocampal and entorhinal cortices suggests a potential impact of CBD in memory deficits typical in healthy aging. However, the evidence relating cannabinoids to these conditions is relatively recent and has been obtained from either biochemical or pharmacological studies. It might be hypothesized that CBDs could be useful to delay or even arrest the progression of functional and structural neuronal degeneration. The investigators will use an episodic memory paradigm to test the effects of THC, CBD and placebo on memory encoding and retention and the underlying neuronal networks on healthy male subjects.

Official Title
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Effects of D-9-Tetrahydrocannabinol (THC) and Cannabidiol (CBD) on Human Episodic Memory Function

Conditions
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Healthy Volunteers

Intervention / Treatment
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* Drug: Tetrahydrocannabinol
* Drug: Cannabidiol
* Drug: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: no acute or chronic disease Exclusion Criteria: opioid intake medication or drug abuse kidney or liver dysfunction claustrophobia none removable metallic parts (e.g. hip replacement)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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Male

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: Basic Science
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Tetrahydrocannabinol<br>10 mg of Tetrahydrocannabinol as capsule (once) | Drug: Tetrahydrocannabinol<br>* 10 mg Tetrahydrocannabinol (capsule, once) oral intake<br>|
| Experimental: Cannabidiol<br>600 mg Cannabidiol capsule (once) | Drug: Cannabidiol<br>* 600 mg Cannabidiol (capsule, once) oral intake<br>|
| Placebo Comparator: placebo<br>placebo capsule (once) | Drug: placebo<br>* placebo (capsule, once) oral intake<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in BOLD (blood oxygen level dependent) responses | Differential changes of the BOLD response under the three different conditions (THC, CBD, placebo) during the learning and the test phase of the memory paradigm | immediate | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in behavioral measures | Differential changes in reaction times and number of correct responses during the three different conditions (THC, CBD, placebo) | immediate |