Marijuana Use Tied to IQ Decline

Teen users who have been repeatedly diagnosed with marijuana dependence during their adolescent years have been shown to have significant decline in IQ scores by the age of 38. During adolescent years the brain is maturing, and cannabis use can disrupt that growth process. In addition to the fall in IQ scores, close friends and family members were noted to report that the subjects were also having problems with memory loss and attention.

This study, performed by Madeline Meier, PhD, of Duke Un...