Adolescents Were More Cognitively Impaired by THC Than Adults at the Same Doses
At THC doses that produced similar subjective intoxication in both groups, adolescents showed dose-dependent cognitive impairments and brain changes that adults did not, suggesting greater vulnerability.
Quick Facts
What This Study Found
Adolescents (18-20) showed dose-dependent impairments in reaction time, response accuracy, and time perception with THC (7.5 and 15 mg) that adults (30-40) did not exhibit. THC decreased P300 brain wave amplitude in adolescents but not adults. Subjective intoxication and heart rate effects were similar in both groups.
Key Numbers
12 adolescents (18-20) vs 12 adults (30-40); THC 7.5 and 15 mg; <20 lifetime uses; dose-dependent cognitive impairment in adolescents only; P300 decreased in adolescents only
How They Did This
Double-blind, placebo-controlled RCT with 12 adolescents (18-20) and 12 adults (30-40), all with fewer than 20 lifetime THC uses. Each received placebo, 7.5 mg, and 15 mg THC capsules across three sessions.
Why This Research Matters
This is one of the first human studies directly comparing THC effects across age groups. The finding that adolescents are more cognitively impaired at doses that feel the same as for adults has important implications for risk communication.
The Bigger Picture
This study provides human evidence for what animal studies have long suggested: the adolescent brain is more vulnerable to THC. The dissociation between feeling equally high and being more impaired is particularly concerning.
What This Study Doesn't Tell Us
Very small sample (24 total). Participants aged 18-20 are legally adults but neurologically still developing. Oral THC capsules may differ from smoked/vaped cannabis.
Questions This Raises
- ?Would these differences persist with regular cannabis use and tolerance development?
- ?Does the P300 reduction in adolescents reflect long-lasting brain changes or only acute effects?
Trust & Context
- Key Stat:
- Adolescents more impaired despite similar subjective intoxication
- Evidence Grade:
- Well-designed double-blind RCT with objective cognitive and EEG measures, but very small sample size (24 total).
- Study Age:
- Published in 2022
- Original Title:
- Adolescents are more sensitive than adults to acute behavioral and cognitive effects of THC.
- Published In:
- Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 47(7), 1331-1338 (2022)
- Authors:
- Murray, Conor H(5), Huang, Zhengyi, Lee, Royce, de Wit, Harriet
- Database ID:
- RTHC-04089
Evidence Hierarchy
Participants are randomly assigned to treatment or placebo groups to test cause and effect.
What do these levels mean? →Frequently Asked Questions
Are young people more affected by THC than adults?
Yes. This study found adolescents (18-20) had dose-dependent impairments in reaction time, accuracy, and time perception that adults (30-40) did not show, even though both groups reported feeling equally intoxicated.
Why is this concerning?
If adolescents feel equally high as adults but are more impaired, they may not recognize their cognitive deficits. This could lead to risky decisions like driving while more impaired than they realize.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-04089APA
Murray, Conor H; Huang, Zhengyi; Lee, Royce; de Wit, Harriet. (2022). Adolescents are more sensitive than adults to acute behavioral and cognitive effects of THC.. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 47(7), 1331-1338. https://doi.org/10.1038/s41386-022-01281-w
MLA
Murray, Conor H, et al. "Adolescents are more sensitive than adults to acute behavioral and cognitive effects of THC.." Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 2022. https://doi.org/10.1038/s41386-022-01281-w
RethinkTHC
RethinkTHC Research Database. "Adolescents are more sensitive than adults to acute behavior..." RTHC-04089. Retrieved from https://rethinkthc.com/research/murray-2022-adolescents-are-more-sensitive
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.