Processing of Salient Emotional Stimuli as a Function of Tetrahydrocannabinol (THC) and Cannabidiol (CBD)

Study Overview
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Brief Summary
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Attentional blink refers to a phenomenon where the detection of the second of two target stimuli that are presented in Short succession within a stream of stimuli is impaired. This is explained by an insufficient availability of attentional resources. Additionally, emotionally salient stimuli, like for example pictures with a positive or negative content, are detected more often compared to neutral pictures during this attentional blink period. Cannabinoids are involved in the modulation of cognitive, attentional, and emotional processes. Interestingly, data from animals suggests that THC and CBD, both active ingredients in the Cannabis sativa plant, have opposing effects on brain cannabinoid (CB1) receptors. CB1 receptors modulate the expression of emotionally salient conditioned association in rats, if salience processes in humans are modulated in the same way remains unclear. Employing a task to detect salient stimuli, Bhattacharyya et al. (2012) showed that THC seems to make non-salient standard stimuli more salient. They showed decreased activation of the right caudate and increased right prefrontal cortex stimuli during processing of salient stimuli. Importantly, this was associated with decreased response times to standard relative to oddball stimuli. Generally, THC and CBD differentially modulate brain areas associated with attentional salience processing. For example THC seems to increase prefrontal and striatal activation whereas CBD seems to decrease it. The investigators assume that THC increases the number of correctly detected emotional stimuli during the attentional blink period, whereas CBD has no effect. Additionally, the investigators assume that pictures of the positive category are detected with higher accuracy than negative ones under the influence of THC.

Official Title
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Processing of Salient Emotional Stimuli as a Function of Tetrahydrocannabinol (THC) and Cannabidiol (CBD)

Conditions
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Healthy Humans

Intervention / Treatment
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* Drug: tetrahydrocannabinol
* Drug: cannabidiol
* Other: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: male age between 18 and 65 years right-handed Exclusion Criteria: consumption of cannabis more than 5 times substance abuse (apart from nicotine) psychiatric disorders epilepsy chronic diseases (e.g. diabetes)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: tetrahydrocannabinol<br>oral administration of 10mg of tetrahydrocannabinol, once | Drug: tetrahydrocannabinol<br> <br> |
| Experimental: cannabidiol<br>oral administration of cannabidiol, 600mg, once | Drug: cannabidiol<br> <br> |
| Placebo Comparator: placebo<br>oral administration of placebo, once | Other: placebo<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correctly identified emotional pictures during the attentional blink period | Number of correctly identified emotional pictures that were presented during the attentional blink period. | immediate | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reaction time to correctly identified emotional pictures during the attentional blink period | Reaction time (in ms) of the button press to the correctly identified emotional pictures that were presented during the attentional blink period. | immediate | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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THC and CBD, Attentional blink