Weed smokers; thinking decline

The researchers, writing in the US journal Proceedings of the National Academy of Sciences, found that: “Persistent cannabis use over 20 years was associated with neuropsychological decline, and greater decline was evident for more persistent users.” I guess the success of Richard Branson, Willie Nelson ,Barack Obama and many others, will be use to contest the findings. I think the word LONG term usage  will  damage the smoker of marijuana.   I say: Feed the hungry, give shelter to the homeless, and jobs for the unemployed.