There is new ammunition for those opposed to legalizing even small amounts of marijuana in New Jersey. A new study published Wednesday in the Journal of Neuroscience by researchers at Northwestern University, in collaboration with Massachusetts General Hospital and Harvard Medical School, links significant brain abnormalities to the casual use of pot by young adults.

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"This just really solidifies what we have known in the prevention field for many years; marijuana is a damaging drug," said Assemblywoman Mary Pat Angelini (R-Monmouth). "This is science. This is evidence that's showing that legalizing marijuana is not a good idea."

The study matched only a small sample of 20 marijuana smokers and 20 control subjects ranging in age from 18 to 25. Using magnetic resonance imaging, the researchers found significant abnormalities in the areas of the brain responsible for making decisions, processing emotions and motivation, even among those who smoked marijuana just once or twice a week.

"Northwestern University is the real deal, and this study tells us there are changes in our brain functions with only casual use of marijuana," Angelini said.

Legislation in the works in New Jersey would legalize the possession of up to an ounce of marijuana, that could be purchased at a facility licensed by the state. Supporters of that bill are quick to point out that there are other studies which conclude marijuana use is no more dangerous -- and could be less dangerous -- than alcohol and tobacco.

"We know that alcohol and tobacco cause damage, and we know for a fact that we don't need another drug thrown into the mix as well," Angelini said.

The full study can be found at www.northwestern.edu.