All known drugs of abuse increase dopamine and likewise cause decrease in dopamine during drug withdrawal [1]. Since the participants in the study in question w

All known drugs of abuse increase dopamine and likewise cause decrease in dopamine during drug withdrawal [1]. Since the participants in the study in question were chronic cannabis users who stayed abstinent 5-7 days before the brain scans [2], it is plausible to attribute the results to the cannabis withdrawal. It would be interesting to see the results of a similar experiment where the subjects were given enough time for their brains to normalize the dopamine receptors (let's say at least a month). My hypotesis is that their dopamine levels would be closer to normal. 1. http://perspectivesinmedicine.cshlp.org/content/2/8/a012229.full http://perspectivesinmedicine.cshlp.org/content/2/8/a012229.... 2. http://www.nature.com/mp/journal/vaop/ncurrent/full/mp201621a.html http://www.nature.com/mp/journal/vaop/ncurrent/full/mp201621...