Study: Nicotine Changes The Way Marijuana Affects The Brain
By Steve Elliott
Nicotine changes the way marijuana affects the brain, according to a new study from scientists at the University of Texas at Dallas.
When marijuana and tobacco are combined, according to the study, which was published in the journal Behavioural Brain Research, memory gets stronger as the hippocampus, an area of the brain which affects learning ability and memory, gets smaller, reports Sean Martin at the International Business Times. The more cigarettes smoked per day, the smaller the size of the hippocampus, and the greater the memory performance, according to the research.
The team concluded that the effects of marijuana on the brain aren't usually analyzed with tobacco taken into consideration. The research team was led by Francesca Filbey, director of cognitive neuroscience of addictive behaviors at the Center for BrainHealth.
"Approximately 70 percent of individuals who use marijuana also use tobacco," Filbey said (although I'd question that number). "Our findings exemplify why the effects of marijuana on the brain may not generalize to the vast majority of the marijuana using population, because most studies do not account for tobacco use. This study is one of the first to tease apart the unique effects of each substance on the brain as well as their combined effects.
"We have always known that each substance is associated with effects on the brain and hypothesized that their interaction may not simply be a linear relationship," Filbey said. "Our findings confirm that the interaction between marijuana and nicotine is indeed much more complicated due to the different mechanisms at play. Future studies need to address these compounding effects of substances.
"The combined use of marijuana and tobacco is highly prevalent," Filbey said. "For instance, a 'blunt' is wrapped in tobacco leaf. We really need to understand how the combined use changes the brain to really understand its effects on memory function and behavior."