Charles P. O'Brien, MD, PhD

O’Brien’s work, beginning in the 1970s, showed that the fundamental mechanism of addiction was a conditioned response, thus providing the foundation for the current concept of addiction as a brain disease.  He also showed that alcohol activated the endogenous opioid system and demonstrated the efficacy of blocking opioid receptors using naltrexone in the treatment of alcoholism, a treatment now used around the world. Recent work suggests a variant of the µ opioid receptor gene as associated with this form of alcoholism. His team also developed a system for measuring addiction severity and developed other medications and behavioral treatments.  As a result of his work over the past 30 years, our understanding and treatment of all kinds of addiction have markedly improved.