This story reports that scientists have for the first time discovered the location where the active ingredient of marijuana (tetrahydrocannabinol) effects the brain. This discovery is due in large measure to the fairly recent discovery of the cannabinoid receptor in humans. This discovery was quite monumental because it proved that the body naturally produces its own "cannabis" known endocannabinoids. It has been shown that cannabinoid receptors are not only located in the brain but also the liver. As such, chronic consumption of marijuana may be associated with liver impairment. Although governmental officials have fired the warning shot about the potency of modern marijuana, there's much more we need to know before making any sweeping statements about the harm of recreational marijuana use. Many people experiment with marijuana without any apparent long term effects. Nonetheless, these studies deserve attention, as it does appear that the potency of most available marijuana is on the rise. The flip side of the scientific progress made in terms of marijuana and the cannabinoid system is that while chronic use of high potency marijuana probably has adverse effects on the body, small doses may indeed have medicinal value.