Investigating how cannabis affects memory and brain activity

Cannabis Observations on Brain Waves, Retrieval, and Attention: Experiment 3 (COBRA)

This study is testing how different types of cannabis, one with more THC and another with both THC and CBD, affect memory and brain activity in healthy regular users.

Quick facts

• Study type: Observational
• Enrollment: 64 (estimated)
• Ages: 21 Years to 40 Years
• Sex: All
• Sponsor: University of Colorado, Boulder (Academic / other)
• Locations: 1 site (Boulder, Colorado)
• Trial ID: NCT06669585 on ClinicalTrials.gov

What this trial studies

This observational study examines the effects of THC and CBD on recognition memory in healthy, regular cannabis users. Participants will complete a memory task after using either a THC-dominant strain or a strain containing both THC and CBD, with brain activity measured through electroencephalography (EEG). Blood samples will be collected to assess cannabinoid exposure, and participants will also provide self-reports on various health and lifestyle factors. The study aims to better understand the cognitive impacts of different cannabis strains on memory performance.

Who should consider this trial

Good fit: Ideal candidates are healthy, right-handed adults aged 21 to 40 who are regular cannabis users.

Not a fit: Patients who do not use cannabis regularly or who have a history of substance abuse may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide insights into how different cannabis compounds affect memory, potentially guiding safer usage for cognitive health.

How similar studies have performed: Previous studies have indicated cognitive impairments associated with cannabis use, but this study's focus on specific cannabinoid interactions is relatively novel.

Eligibility criteria

Inclusion Criteria:

1. Must be between the ages of 21 and 40 and provide informed consent;
2. Must be right-handed (Laterality Quotient \> 60 on Edinburgh Handedness Inventory - Short Form);
3. Must use cannabis at least 4 days during the month;
4. Must be a cannabis user for at least a year;
5. Must self-report not using other illicit recreational drugs (e.g., cocaine, benzodiazepines (non-prescription), opiates (non-prescription), MDMA, sedatives, or methamphetamine) in the past 30 days, during the Pre-Screening;
6. Must not test positive on a urine toxicology test for drugs of abuse at the Baseline appointment;
7. Must not be using psychotropic medications, however anti-depressant, non-benzodiazepine anti-anxiety, and ADHD medications are ok. ADHD medication users must be willing to abstain from ADHD medication use on appointment days;
8. Must not be a regular nicotine user (≤4 days per week; cigarette, E-cigs, or smokeless);
9. Must not have used caffeine or nicotine (cigarette, E-cigs, or smokeless) for 4 hours before each appointment;
10. Must have a breath alcohol level of 0 at Baseline appointment (to sign consent form);
11. Must not be actively seeking or in treatment for any substance use disorder;
12. Female subjects must not be or trying to become pregnant (as indicated by a pregnancy test administered at Baseline appointment);
13. Must not be in treatment for psychotic disorder or bipolar disorder; or have a history with these disorders;
14. Must not have any physical characteristics (e.g., thick hair, head size exceeding the limit of the net, dyed hair) or experience any technical difficulties during testing that result in a poor-quality EEG recording.

Where this trial is running

Boulder, Colorado

• Center for Innovation and Creativity (CINC) — Boulder, Colorado, United States (Recruiting)

Study contacts

• Principal investigator: Timothy Curran, PhD — University of Colorado, Boulder
• Study coordinator: Katie N Paulich, PhD

Conditions Cannabis; Memory; Electroencephalography