A new study says the impact of marijuana on teenage brains is worse than alcohol.
Researchers found that teens who smoked marijuana have more cognition problems than those who drank alcohol.
Doctors discovered that pot-smoking teens have delayed memory recall and delayed responses.
The study involved more than 3,800 seventh-grade students. The results were published in the American Journal of Psychiatry .
The new study backs up older studies that say cannabis impacts brains.