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

Not Applicable

Completed

• Conditions: Healthy Humans
• Interventions: Other: placebo; Drug: cannabidiol; Drug: tetrahydrocannabinol

• Registration Number: NCT02291536
• Lead Sponsor: Central Institute of Mental Health, Mannheim

Brief Summary

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.

Detailed Description

Not available

Study Timeline

• Study Start: 2014-02
• Status Verified: 2014-11
• Study First Submitted: 2014-11-11
• Study First Submitted QC: 2014-11-13
• Study First Posted: 2014-11-14
• Primary Completion: 2014-12
• Study Completion: 2014-12
• Last Update Submitted: 2015-01-15
• Last Update Posted: 2015-01-16

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 20

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)

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
placebo	placebo	oral administration of placebo, once
cannabidiol	cannabidiol	oral administration of cannabidiol, 600mg, once
tetrahydrocannabinol	tetrahydrocannabinol	oral administration of 10mg of tetrahydrocannabinol, once

Primary Outcome Measures

Name	Time	Method
Correctly identified emotional pictures during the attentional blink period	immediate	Number of correctly identified emotional pictures that were presented during the attentional blink period.

Secondary Outcome Measures

Name	Time	Method
Reaction time to correctly identified emotional pictures during the attentional blink period	immediate	Reaction time (in ms) of the button press to the correctly identified emotional pictures that were presented during the attentional blink period.

Trial Locations

Locations (1)

Central Institute of Mental Health; 🇩🇪 Mannheim, Germany