Natasha Wade, PhD, highlights slower cognitive growth after teen cannabis use

According to Natash Wade, PhD, assistant professor at University of California San Diego, pediatricians should interpret emerging data on adolescent cannabis use with a focus on prevention, early monitoring, and clear communication with patients and families.

Findings from longitudinal research suggest a nuanced pattern: adolescents who initiate cannabis use may demonstrate relatively stronger baseline cognitive performance but experience slower neurocognitive growth over time. This trajectory underscores that early apparent strengths do not confer protection against later cognitive effects. Instead, cannabis exposure during a critical period of brain development may alter expected gains in thinking and learning abilities.

Clinically, the most consistent signal across studies is the vulnerability of memory, particularly episodic memory. Evidence from human cohorts, toxicology-based analyses, and preclinical models converges on memory as a domain especially sensitive to cannabis exposure.

However, the impact is not isolated; multiple cognitive domains show altered developmental trajectories, indicating that cannabis may have broad effects on brain function. For pediatricians, this supports incorporating cognitive surveillance—especially memory assessment—into care for adolescents at risk of or known to be using cannabis.

Distinguishing between cannabis constituents is also clinically relevant. Delta-9-tetrahydrocannabinol (THC), the primary psychoactive component, appears to be more strongly associated with adverse cognitive outcomes than cannabidiol (CBD).

Data linking THC exposure to declines in episodic memory suggest that THC may be a key driver of observed neurocognitive changes. This distinction is important given the increasing availability and perceived safety of CBD products; clinicians should clarify that not all cannabis-related compounds carry the same risk profile, while still emphasizing caution.

Another important takeaway is the value of combining self-report with objective toxicology measures, such as hair or urine testing. Research indicates that relying solely on self-report may underestimate cannabis exposure, as a substantial proportion of adolescents may not disclose use.

Incorporating objective measures can improve identification and risk stratification, though in routine practice, this may not always be feasible. As a result, pediatricians are encouraged to provide anticipatory guidance universally, rather than only when use is suspected.

Finally, the persistence of associations between cannabis use and cognitive outcomes—even after adjusting for confounding factors such as prenatal exposures, mental health conditions, and other substance use—reinforces the need for proactive prevention.

Pediatric providers should prioritize early, consistent education about the potential cognitive risks of cannabis and encourage delaying initiation. Framing guidance around brain development and long-term cognitive health may help adolescents and families make more informed decisions.

No relevant disclosures.

Reference

Largest US study finds teen cannabis use linked to slower cognitive development. University of California San Diego. April 19, 2026. Accessed April 23, 2026. https://www.eurekalert.org/news-releases/1124373?