On the Shoulders of Giants 2013
Nora Volkow and proteges on addiction, obesity, brain mechanisms and bacon
Child Mind Institute
Earlier this week the Child Mind Institute had the pleasure of hosting its third annual On the Shoulders of Giants scientific symposium, this year honoring National Institute on Drug Abuse director Nora Volkow and two of her scientific "descendants," as it were. Because of the federal government shutdown, Dr. Volkow had to prerecord her remarks for playback at Hunter College's Roosevelt House in New York City—a fact that appeared to have escaped the audience by the end of her talk, when they applauded her as if she were in attendance.
Dr. Volkow's presentation summed up her groundbreaking work in drug addiction, which shows definitively that chemical dependency is a disease of the brain. Her central finding is a fascinating reinforcement of common sense: people abuse drugs even though it does them no good. More specifically, brain studies pioneered by Dr. Volkow show that the brains of addicts are inured to the drugs they take in terms of dopamine release—the thing that gets a person "high" the first time he tries cocaine, for instance. Then why do they take them? Because the anticipation of their possible effect releases dopamine, the neurotransmitter associated with pleasure and reward.
This insight isn't entirely new—conditioning, as it's called, goes back to Pavlov. Conditioned responses "happen with food, happen with sex, happen with drugs," Dr. Volkow said. But her work has shown the specific neural basis of this behavior, which she calls the "cue response." In short, she said, "drug-addicted people can pay extremely high costs in order to procure the drug that they are craving even though the drug itself produces extremely low dopamergic signals. You have transferred the value of the reward into the cue response, and it completely disrupts a person's behavior—so that they become a slave of those conditioned responses." The ready availability of pleasure has, in essence, short-circuited the brain with disastrous consequences.
Her protege, Gene-Jack Wang, took this idea further in a wide-ranging and often humorous talk that suggested that addiction can apply to what we eat, establishing a clinical model for obesity and also bringing up profound questions of how humans relate to our environment. Dr. Wang, research professor at Stony Brook University, elaborated on an unspoken point of Dr. Volkow's talk: that the very fact of addiction represents the brain's untutored response to something it is not evolutionarily prepared for—a hijacking of usually beneficial pathways.
"This is a problem in our evolution," Dr. Wang said, an inability for our nature to adapt to a distinct change from our "primitive state" to "modern American life." What is the problem? Processed foods. Dr. Wang demonstrated identical brain responses in drug addicts and morbidly obese people, suggesting without reservation that for some people modern food is a drug of abuse, and that many of us are equally unprepared to deal with synthetic sustenance as we are with synthetic pharmaceuticals. "We've never had this life," he said. We have access to "all kinds of food, very tasty." Our response to this, unfortunately, is "maladaptive." One solution, Dr. Wang said, is to educate people about what they need to eat, as opposed to what they can.
Finally, Dr. Wang's former student, Michael Michaelides, took these observations and described how he applies them to animal models of addiction and very specific brain mechanisms. The methods he uses seemed at times to come from science fiction, but the promise for understanding and treating real and pervasive problems in the modern world was palpable. Dr. Michaelides, a postdoctoral researcher at Mount Sinai, also has fascinating stories about rodents, bacon, and alcohol, as well as methods like DREADD and DREAMM. You should check out this intrepid researcher.
The symposium was also an occasion to honor the second annual class of Child Mind Institute Rising Scientists, many of whom were in attendance along with their proud parents. The Rising Scientists are New York City metropolitan area high school students who have demonstrated particular aptitude, dedication, and insight in their studies of everything from biology to aeronautics. The wide range of the awardees' interests exemplifies a core principle of the Child Mind Institute, and one that Dr. Volkow so eloquently elaborated in her presentation: that progress on stubborn issues like addiction or pediatric mental illness require collaboration between disciplines that have historically been segregated.
Our understanding of addiction, Dr. Volkow said at the beginning of her talk, depends on the "effort of very diverse individuals." They were the ones responsible for the "development of instrumentation," from "physicists to the chemists who developed the radioligand," the key to a precise picture of the actions of chemicals in the brain. They include "the physicians who can take a finding from a human into an animal to actually determine causality," and the other scientists who "take the findings from the animal and see if it pertains to the human condition." It takes a village, so to speak—a very qualified village.
And, of course, fresh thinking. Dr. Harold Koplewicz, president of the Child Mind Institute, spoke admiringly of one Rising Scientist's detailed and optimistic plan for a lunar base to open midway through this century. Equally hopeful, he noted, is one student's desired profession: psychiatrist. Perhaps these two exceptional young people will one day find a way to work together.
Published: October 6, 2013