THC shifted attention toward cannabis cues in a controlled vaping experiment with teens and adults

In a controlled crossover study, participants on placebo tended to look away from cannabis images, but THC eliminated this avoidance pattern. Adding CBD did not change the effect, and teens responded similarly to adults.

Hall, Daniel et al.·Psychopharmacology·2024·Moderate Evidencerandomized controlled trial
RTHC-05364Randomized controlled trialModerate Evidence2024RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
randomized controlled trial
Evidence
Moderate Evidence
Sample
N=24

What This Study Found

In a three-condition crossover trial (THC, THC+CBD, placebo), participants showed an attentional bias away from cannabis cues on placebo. THC administration eliminated this avoidance pattern (F(2,92) = 3.865, p = 0.024). CBD did not moderate the effect, and there was no significant difference between adolescents and adults.

Key Numbers

48 participants (24 adolescents, 24 adults); 3 conditions: THC (8 mg/75 kg), THC+CBD (8 mg + 24 mg/75 kg), placebo; main drug effect F(2,92) = 3.865, p = 0.024, η2p = 0.077; 200-ms trials

How They Did This

Randomized, double-blind, placebo-controlled, crossover study with 48 weekly cannabis users (24 adolescents aged 16-17, 24 adults aged 26-29) who received weight-adjusted vaporized cannabis (THC alone, THC+CBD, or placebo) on three separate days and completed a visual probe task with cannabis cues.

Why This Research Matters

Attentional bias toward drug cues is thought to contribute to addiction. This finding that THC shifts attention toward cannabis cues could help explain how cannabis use reinforces continued use.

The Bigger Picture

The finding that THC eliminates avoidance of cannabis cues adds to the understanding of how cannabis may create self-reinforcing attention patterns, a mechanism proposed to drive addictive behavior across substances.

What This Study Doesn't Tell Us

Small sample size (48 total); participants were already weekly cannabis users so findings may not apply to non-users; moderate dose may not reflect real-world heavy use; single session per condition

Questions This Raises

  • ?Does this attentional shift persist after THC wears off?
  • ?Would higher CBD doses show a moderating effect?
  • ?Does the magnitude of this shift predict who develops problematic use?

Trust & Context

Key Stat:
48 participants in three-condition crossover trial
Evidence Grade:
Well-designed crossover RCT with appropriate blinding and controls, but small sample limits statistical power for subgroup analyses.
Study Age:
2024 study
Original Title:
The acute effects of cannabis, with and without cannabidiol, on attentional bias to cannabis related cues: a randomised, double-blind, placebo-controlled, cross-over study.
Published In:
Psychopharmacology, 241(6), 1125-1134 (2024)
Database ID:
RTHC-05364

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study
What do these levels mean? →

Frequently Asked Questions

What happened to attention when people were given THC?

On placebo, participants tended to look away from cannabis-related images. When given THC, this avoidance disappeared, meaning attention was no longer directed away from cannabis cues. Researchers believe this shift could contribute to addiction by making cannabis cues more salient during intoxication.

Did CBD make any difference?

No. Adding CBD (at a 3:1 ratio to THC) did not significantly alter the attentional effects of THC. The researchers also found no difference between how adolescents and adults responded to any condition.

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Cite This Study

RTHC-05364·https://rethinkthc.com/research/RTHC-05364

APA

Hall, Daniel; Lawn, Will; Ofori, Shelan; Trinci, Katie; Borissova, Anya; Mokrysz, Claire; Petrilli, Kat; Bloomfield, Michael A P; Wall, Matthew B; Freeman, Tom P; Curran, H Valerie. (2024). The acute effects of cannabis, with and without cannabidiol, on attentional bias to cannabis related cues: a randomised, double-blind, placebo-controlled, cross-over study.. Psychopharmacology, 241(6), 1125-1134. https://doi.org/10.1007/s00213-024-06543-7

MLA

Hall, Daniel, et al. "The acute effects of cannabis, with and without cannabidiol, on attentional bias to cannabis related cues: a randomised, double-blind, placebo-controlled, cross-over study.." Psychopharmacology, 2024. https://doi.org/10.1007/s00213-024-06543-7

RethinkTHC

RethinkTHC Research Database. "The acute effects of cannabis, with and without cannabidiol,..." RTHC-05364. Retrieved from https://rethinkthc.com/research/hall-2024-the-acute-effects-of

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.