I am here remitting you to the link on  the Volkow article in the NY Times … http://www.nytimes.com/2011/06/14/science/14volkow.html?pagewanted=all

And to Baldo’s rebuttal (in very general terms and my reading/interpretation of his criticism) which is based on the fact that addiction under 'Prohibition' is considered a true, objective physical illness and can thus be studied and treated much like if we considered that there is a such a thing as “behavioural cancer”.

..."Dr Volkow basically states that Dopamine, the pleasure hormone, is as the heart of addiction. I have no wish to challenge the facts. What I think is that if we wish to dub the verifiable phenomenon as “addiction” (although “habit” would be preferable) that we, nonetheless free this phenomenon from any and all pathological connotation and, by so doing,  enquire into the hazardous or healthy  nature of each particular “addiction” and evaluate it through rigorous medical criterion.   

International drug policy is not based on “good science”, contrary to what Dr Kolkow sustains. It is based on a prejudiced “paradigm” which has undermined prior medical assessments on the effects of these plants on the nervous system.

It is now up to neuroscientists to clarify the view which focuses on the behavioural “epidemic” which addiction has been made out to be and to get past the interests of the pharmaceutical industry."....

Baldo's very reasonable insanity