Does light marijuana usage in teens hinder full brain development?

Could. Marijuana is a psychoactive drug and messes with the brain, more so when the brain is still developing. It may also lead to use of other street drugs. Users are called stoners for good reason. Quitting this self-destructive behaviour is imperative. Wish you good health!

There are indeed medical literature reports of cognitive impairment and emotional abnormalities in many adolescents who have had a history of marijuana use. This is best to be avoided until full maturation.