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

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.

Study Overview

• Status: Completed
• Conditions: Healthy Humans
• Intervention / Treatment: Other: placebo; Drug: tetrahydrocannabinol; Drug: cannabidiol

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Germany
  • Mannheim, Germany, 68159
    • Central Institute of Mental Health

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Male

Description

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 Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Single Group Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: tetrahydrocannabinol; oral administration of 10mg of tetrahydrocannabinol, once	Drug: tetrahydrocannabinol
Experimental: cannabidiol; oral administration of cannabidiol, 600mg, once	Drug: cannabidiol
Placebo Comparator: placebo; oral administration of placebo, once	Other: placebo

What is the study measuring?

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

Collaborators and Investigators

• Sponsor: Central Institute of Mental Health, Mannheim
• Investigators: Principal Investigator: Oliver Grimm, MD, Central Institute of Mental Health, Mannheim

Study record dates

Study Major Dates

• Study Start: February 1, 2014
• Primary Completion (Actual): December 1, 2014
• Study Completion (Actual): December 1, 2014

Study Registration Dates

• First Submitted: November 11, 2014
• First Submitted That Met QC Criteria: November 13, 2014
• First Posted (Estimate): November 14, 2014

Study Record Updates

• Last Update Posted (Estimate): January 16, 2015
• Last Update Submitted That Met QC Criteria: January 15, 2015
• Last Verified: November 1, 2014

More Information

Terms related to this study

• Keywords: Attentional blink; THC and CBD
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Analgesics, Non-Narcotic; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Psychotropic Drugs; Anticonvulsants; Hallucinogens; Cannabinoid Receptor Agonists; Cannabinoid Receptor Modulators; Dronabinol; Cannabidiol
• Other Study ID Numbers: AB_THC_CBD