Adolescent Cannabis Receptor Activation Disrupts Adult Brain Rhythms (Preprint)
This preprint version of RTHC-00197 provides additional methodological detail—including sex-balanced cohorts and extended testing windows—on lasting hippocampal theta disruptions from adolescent cannabinoid exposure.
Quick Facts
What This Study Found
This is the preprint (bioRxiv) version of the study published as RTHC-00197. The core finding is identical: sub-chronic activation of cannabinoid CB1 receptors during peri-adolescence in rats produces lasting abnormalities in hippocampal theta synchronization that persist into adulthood.
The preprint provides additional detail on the experimental design. The cohort included sex-balanced groups (6 males, 5 females in the treatment group; 4 males, 4 females in controls), though the abstract doesn't specify whether sex differences were observed. Some animals were tested at a later timepoint (PND 111–115 vs. the standard PND 70–88), suggesting the researchers were investigating whether the effects persisted even longer.
The preprint also emphasizes the cognitive dimension more explicitly than the journal version, noting that "recent findings indicate that cognitive domains may also be at risk" beyond the historically primary concern about psychosis. This framing connects the electrophysiological findings to real-world cognitive concerns about adolescent cannabis use.
The theta rhythm findings have relevance to both schizophrenia (where theta abnormalities are well-documented) and cognitive impairment (where theta oscillations underpin memory encoding and attentional processing).
Key Numbers
Treatment: n=11 (6M, 5F). Vehicle: n=8 (4M, 4F). PND 32–36 or 42–46 pre-treatment (n=10 and 9). Testing at PND 70–88 (n=17) and PND 111–115 (n=2).
How They Did This
Preprint of RTHC-00197. Rats pre-treated with CB1R agonist CP-55940 (n=11, 6M/5F) or vehicle (n=8, 4M/4F) during adolescence (PND 32–36 or 42–46, n=10 and 9). Adult testing at PND 70–88 (n=17) or PND 111–115 (n=2). Hippocampal theta rhythm elicited by brainstem stimulation.
Why This Research Matters
The sex-balanced design is important because cannabis may affect male and female brains differently during development (see RTHC-00191 on prenatal THC and sex-specific amygdala effects). The extended testing window (up to PND 115) helps establish whether effects are truly persistent or eventually fade.
The Bigger Picture
As the preprint companion to RTHC-00197, this provides the same mechanistic support for the adolescent vulnerability hypothesis. The inclusion of both early and late adolescent timepoints parallels RTHC-00191's finding that timing of THC exposure during development matters for outcomes. Together, these animal studies build the case that the adolescent brain has specific windows of cannabinoid vulnerability.
What This Study Doesn't Tell Us
Same limitations as RTHC-00197 plus: this is a preprint that may not have undergone peer review. The very small extended-timepoint group (n=2) limits conclusions about persistence beyond PND 88. Sex-specific analyses aren't described in the abstract despite the balanced design.
Questions This Raises
- ?Were there sex differences in vulnerability to adolescent cannabinoid exposure?
- ?Do the effects persist beyond PND 115?
- ?Will the peer-reviewed version include additional analyses not in the preprint?
Trust & Context
- Key Stat:
- Evidence Grade:
- Preprint (not yet peer-reviewed) of the study published as RTHC-00197—same data with additional methodological detail.
- Study Age:
- Posted on bioRxiv in 2025; the peer-reviewed version is published as RTHC-00197.
- Original Title:
- Altered network function in hippocampus after sub-chronic activation of Cannabis receptors in peri-adolescence.
- Published In:
- bioRxiv : the preprint server for biology (2025) — bioRxiv is a preprint server for biology, where research is shared before peer review.
- Authors:
- Rehn, Johanna(2), Admeus, Lucas(2), Kocsis, Bernat(2)
- Database ID:
- RTHC-07464
Evidence Hierarchy
Tests effects in animals (usually mice or rats), not humans.
What do these levels mean? →Read More on RethinkTHC
- THC-amygdala-anxiety-brain
- anandamide-weed-withdrawal
- cannabinoid-receptors-recovery-time
- cannabis-developing-brain-teenagers
- cant-enjoy-anything-without-weed
- dopamine-recovery-after-quitting-weed
- endocannabinoid-system-explained-simply
- endocannabinoid-system-withdrawal
- nervous-system-weed-withdrawal-fight-flight
- teen-weed-use-under-18-effects-brain
- thc-brain-withdrawal
- thc-prefrontal-cortex-brain-effects
- weed-cortisol-stress-hormones
- weed-memory-loss-recovery
- weed-motivation-amotivational-syndrome
- weed-nervous-system-effects
- weed-reward-system-brain
- thc-and-studying-cannabis-learning-research
Cite This Study
https://rethinkthc.com/research/RTHC-07464APA
Rehn, Johanna; Admeus, Lucas; Kocsis, Bernat. (2025). Altered network function in hippocampus after sub-chronic activation of Cannabis receptors in peri-adolescence.. bioRxiv : the preprint server for biology. https://doi.org/10.1101/2025.09.16.676661
MLA
Rehn, Johanna, et al. "Altered network function in hippocampus after sub-chronic activation of Cannabis receptors in peri-adolescence.." bioRxiv : the preprint server for biology, 2025. https://doi.org/10.1101/2025.09.16.676661
RethinkTHC
RethinkTHC Research Database. "Altered network function in hippocampus after sub-chronic ac..." RTHC-07464. Retrieved from https://rethinkthc.com/research/rehn-2025-altered-network-function-in-2
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.