Researchers scanned the brains of 92 adolescents, ages 16 to 20, before and after an 18-month period. During that year and a half, half of the teens — who already had extensive alcohol and marijuana-use histories — continued to use marijuana and alcohol in varying amounts. The other half abstained or kept consumption minimal, as they had throughout adolescence.
The before-and-after brain scans of the teens consuming typically five or more drinks at least twice a week showed reduced white matter brain tissue health, study co-author Susan Tapert, neuroscientist at University of California, San Diego, told HuffPost. This may mean declines in memory, attention, and decision-making into later adolescence and adulthood, she said.
However, the level of marijuana use — up to nine times a week during the 18 months — was not linked to a change in brain tissue health. The researchers did not test performance; they only looked at brain scans.
The study was conducted by researchers at UC San Diego and is scheduled to be published in the April issue of the journal Alcoholism: Clinical & Experimental Research.
The damage occurs because white matter brain tissue develops throughout adolescence and into a person’s 20s, Joanna Jacobus, postdoctoral fellow at the UC San Diego, and co-author of the study, told HuffPost.
Part of that still-developing brain tissue is where decision-making ability comes from, which can exacerbate substance use. “It becomes a cycle. If teens decrease their tissue health and cognitive ability to inhibit themselves, they might become more likely to engage in risky behavior like excessive substance use,” Jacobus said.
WASHINGTON – When Mitt Romney told a crowd in Ohio last week that he had read a report saying Jeep was “thinking of moving all production to China,” there was at least a potentially defensible explanation.
A Bloomberg story published the previous Monday had stated that Fiat, which owns Chrysler, “plans to return Jeep output to China and may eventually make all of its models in that country.”
A line was added to the Bloomberg story after it was published stating that Mike Manley, chief operating officer of Fiat and Chrysler in Asia, was referring to “adding Jeep production sites rather than shifting output from North America to China.” The Romney campaign told The Huffington Post on Tuesday that the update was after Romney made his remark on Thursday. It’s not clear whether that’s true or not, but what is known is that Chrysler refuted press reports about the Bloomberg story before Romney spoke Thursday evening in Defiance, Ohio.
What has confounded many political observers, and provoked a spirited counteroffensive from the Obama campaign — including their own TV ad — is why the Romney campaign then aired in Ohio a TV commercial that implied the auto bailout had hurt the auto industry and that Chrysler was sending U.S. jobs to China. Chrysler told HuffPost the company has added 11,200 U.S. jobs since going through a managed bankruptcy backed by federal bailout dollars in late 2008 and early 2009. And while Chrysler is going to make Jeeps in China for the Chinese market rather than selling U.S.-built models in China, the company said it is expanding production rather than shifting it, adding shifts and hiring workers in the U.S. at the same time.