Every two years most Waldo County students complete a survey that asks them about a number of issues in their lives including the use of tobacco, alcohol and other drugs.

The results of the Maine Integrated Youth Health Survey completed in February 2009 revealed about 28 percent had used marijuana in the past month, about 36 percent tried marijuana for the first time before age 13, and 42 percent reported that they had tried for the first time at age 15 or younger. We can agree that trying for the first time does not mean, necessarily, continued use. About 57 percent of high school students reported it would be “fairly easy” or “very easy” for them to get marijuana if they wanted some.

With this in mind, it is of concern to read the results of recent research by Dr. Staci Gruber from Harvard Medical School as reported in the Harvard Gazette.

Gruber reported subjects who started using marijuana before age 16 made twice as many mistakes on tests of executive function, which includes planning, flexibility, abstract thinking, and inhibiting inappropriate responses, as those who began smoking after age 16. She presented her findings in November at Neuroscience 2010, the annual meeting of the Society for Neuroscience in San Diego.

Gruber found that early-onset smokers of marijuana, once she evaluated them as young adults, also smoked more — and more often.

“Early-onset smokers smoked twice as often and nearly three times as much,” she said. “Given the prevalence of marijuana use in the United States, these findings underscore the importance of establishing effective strategies to decrease marijuana use, especially in younger populations. These findings are critical, as adolescence is a time of important brain development and the adolescent brain is likely more vulnerable to the effects of drugs than the adult brain.”

Frances Jensen, MD, a professor of neurology at Harvard Medical School is quoted in an article found at WebMD as speculating the marijuana exposure “’is somehow modifying the way that part of the brain [the prefrontal cortex, involved in executive function tasks] is developing, That area is one of the last parts of the brain to develop fully,’ she said, ‘so the teen brain is especially vulnerable.’” Dr. Jensen says of the damage incurred by early-onset smoking of marijuana, “Currently, it looks irreversible.”

Undoubtedly for parents the prospect of irreversible brain damage for their child is frightening. At a time when legalization of marijuana is discussed and debated, it is important for parents to talk early and often about the brain-specific risks associated with marijuana, alcohol, tobacco and other drugs of addiction and to support their child in making healthy choices.

Patrick Walsh is the director of prevention services at Broadreach and the substance abuse prevention coordinator for Healthy Waldo County.