Some teens' marijuana use has been linked to disrupted communication between two key regions in the brain’s reward circuitry at age 20. Disrupted communication between the regions was associated with poorer psychosocial functioning at age 22.
Researchers used the statistical technique of latent class analysis to describe distinct patterns of marijuana use across age using data from nearly 10,000 participants in the Monitoring the Future study. Longer-term marijuana use (extending from age 18 into the late 20s or beyond) was associated with increased risk of self-reported health problems at age 50.
In a clinical trial, N-acetylcysteine did not help adults reduce their cannabis use, despite having been effective for adolescents in a previous trial. The results indicated that if adults are able to benefit from the medication, they will likely require a different treatment regimen than adolescents.
A brain imaging study strongly suggests that regular users of marijuana have smaller orbitofrontal cortex (OFC) volumes. Such a deficit could make it more difficult to change counterproductive behaviors, including drug use.
Legally protected marijuana dispensaries (LMDs) were associated with lower rates of dependence on prescription opioids, and deaths due to opioid overdose, than would have been expected based on prior trends. However, LMDs also were associated with higher rates of recreational marijuana use and increased potency of illegal marijuana.
Can marijuana use put offspring at heightened risk for opiate addiction, even if the use stops before the offspring are conceived? Results from a recent NIDA-funded study are consistent with other studies suggesting that a parent’s history of drug use, even preconception, may affect a child’s brain function and behavior.
Dr. Kevin M. Gray discusses why it’s the perfect time for discovering new evidence-based treatments for marijuana dependence. In an accompanying podcast, he discusses a clinical trial that examines NAC’s potential as a treatment for marijuana dependence among adults.
Within the 2 weeks prior to responding to a nationwide survey, 28 percent of high school seniors were in a vehicle whose driver had been using marijuana or another illicit drug, or had drunk 5 or more alcoholic drinks.
Driving under the influence of marijuana is a dangerous public health concern. NIDA researchers have discovered that breath expelled into a Breathalyzer-style collection device contained measurable amounts of THC for up to 2 hours after participants in a recent clinical trial smoked the drug.
Exposing rats to THC increases the likelihood that the animals will later self-administer nicotine. THC-exposed rats are also willing to work harder to obtain nicotine. When extrapolated to people, the findings suggest that THC’s pharmacological impact on the brain may make a person who uses marijuana more vulnerable to developing nicotine addiction, an underappreciated health consequence of marijuana use.
Almost one-third (32 percent) of the roughly 42,000 Monitoring the Future survey respondents reported having used marijuana during their lifetime. However, abuse of many other drugs—methamphetamine, heroin, cocaine, and some prescription medications—declined.
Teen mothers on three American Indian reservations improved on several measures of parenting after participating in Family Spirit, a home-visiting intervention developed with NIDA support. At 12 months postpartum, the women’s children exhibited reduced rates of emotional difficulties predicting later drug abuse and other behavioral problems. Infants at highest risk—those whose mothers had histories of drug abuse—benefited the most.