Charles O’Brien gets frequent invitations to speak in Europe. The Penn psychiatry professor is fluent in French, which helps. And his area of expertise—the study and treatment of addictions—finds interested audiences wherever he travels.

Still, when O’Brien, vice chair of Penn’s Department of Psychiatry and director of the Center for the Study of Addictions at the School of Medicine, was invited by the University of Amsterdam in Holland to deliver the 2004 “Anatomy Lesson” lecture, he was surprised. Though familiar with the famous painting of that name by Rembrandt, he knew little about the annual tradition.

But, impressed with the caliber of past presenters—including Harold Varmus the former director of the National Institutes of Health and a Nobel Prize-winner—O’Brien accepted the invitation to share his research at the November lecture.

Then he began reading up on the history of the Anatomy Lesson. “It turns out Dutch physicians in the 15th and16th centuries were very influential in pioneering modern medicine,” says O’Brien. “In 1563 they got permission from the Spanish king who was the ruler of Holland to take one dead criminal a year and do a dissection for the town people so they could see what’s inside a body. It was sort of a tradition in Europe to have scientists speak to the people.”

Though the modern Anatomy Lesson—resurrected in 1990—features a lecture in place of an autopsy, the tradition of speaking to the general citizenry persists.

“It was one of the larger crowds I’ve spoken to,” O’Brien says of the 2,200-strong audience that packed into Amsterdam’s historic Concertgebouw. “People were standing in the aisles, and it was pretty special because many were just educated people from the community.”

To make his talk resonate with experts and non experts alike, O’Brien says he pitched it “as if I was going on the ‘Larry King Show,’ or ‘Good Morning America,’ which I’ve actually done a number of times over the years.” The topic of addiction, he finds, always touches a nerve. “Everybody,” he says, “thinks they know something about addiction.”

Here at Penn, O’Brien, who is also director of psychiatric research at the Veteran’s Administration Medical Center, has been leading the way in treating addiction as, “a disease of the brain, a chronic disease like high blood pressure or diabetes.” O’Brien and his team have also pioneered new treatments, including an opiate receptor antagonist for alcoholism. “We have shown that alcohol activates the endorphin system and produces euphoria,” he explains. “ When we block receptors for that we block the high and we reduce relapses.“ The treatment, under the name Naltrexone, is now being used all over the world.

O’Brien devoted much of his talk to nicotine addiction. ”I always talk about that quite a bit,” he says, since the addiction is so pervasive and hard to overcome. In Europe, he says, though smoke-free restaurants are still a rarity, “they’re waking up.” This is one area, he adds, where “America has led the world. We’ve really cut back and drawn attention to the problem.”O’Brien also touched on caffeine dependence, a natural follow up to the pre-lecture concert where the orchestra performed, among other pieces, Bach’s Coffee Cantata.