This is what happens if you smoke cannabis every week as a teenager

Teenagers who regularly smoke cannabis risk long-term cognitive impairment and are more likely to develop severe psychiatric disorders, according to a new study.

Lead researcher Asaf Keller says those who smoke the drug around this age, specifically 13 to 15, are more likely to develop conditions including schizophrenia, as well as permanent reductions in intelligence.

To draw these conclusions; researchers at the University of Maryland School of Medicine measured the brain activity of adolescent mice after they were exposed to low levels of cannabis for 20 days.

The results showed abnormal “cortical oscillations” in their brains, which are integral for many cognitive processes, and are also abnormal in the brains of those with schizophrenia.

These oscillations are developed during adolescence, which could be why the risks are heightened for those who regularly use the drug around this age.

The drug affected many functions of the mice's brains, including sensory processing and motor planning.

These problems persisted into adulthood for the mice.

The researchers repeated the experiment on older mice and the results were different – showing that the effects were specific to younger brains.

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