Hi There, thanks for asking. It is an interesting topic. Cannabis has many (more than four hundred) active substances. Three of them are major ones and THC and Cannabidi and Cannabinol. They exert different effects because of the variety of the substances exist in it. Because they are derived from a natural plant, the properties varies from one plant to another. That makes its effect to be npredictable in each time which is consumed. Because most of the mechanism they act in hallucinogenic, they may cause permanent psychosis. Pure THC is used in medicine to control nausea or pain, but marijuana can affect many neurotransmitters like serotonin and dopamine as you mentioned secondary to nonspecific activation. So, its regular usage is strongly discouraged. I wish you the best enjoyment form life.