Thanks to the relentless beat of drug marketing, many of us are confident that depression has been figured out. We “know” that the cause is a chemical imbalance and that the most effective treatment is antidepressants. Since the introduction of SSRIs, which increase the levels of serotonin between brain cells, most scientific research has focused on how these drugs, and others like them, influence depression. In fact, the depression “story” has been dominated by the role of serotonin and the theory that low levels of this neurochemical affect our moods in negative ways.
But I haven’t been able to buy into it. If these drugs are such an effective treatment for depression, why, despite millions of patients in the United States receiving prescriptions for SSRIs each year, are depression rates higher than ever? The World Health Organization estimates that depressive and anxiety disorders lead the list of mental illnesses across the globe—with 121 million people currently suffering from these conditions. They’re responsible for approximately one quarter of all visits to health care centers worldwide. In the United States, where SSRIs, are readily available (about 189 million prescriptions were written for antidepressants for approximately 15 million Americans in 2005 alone!), the Washington Post recently reported that the percentage of adults using SSRIs between 1994 and 2002 had tripled. But despite the astounding number of people on these medications, depression rates continue to rise.
Clearly, this is a problem that still needs to be solved. In fact, for years now, there’s been a growing consensus in the scientific community that serotonin isn’t the central piece of the depression story. The search for what is at the heart of this devastating emotional disorder motivated me to reopen the case and reexamine this mystery called depression.
Investigating the mysteries of the brain is nothing new for me. A significant portion of my research in the lab has focused on the effects of chronic stress and anxiety on the mammalian brain. Using animal models of anxiety and depression, I have searched for consistent patterns of coping and resilience. Over the past two decades, my students and I have been fortunate to have the opportunity to present approximately one hundred research studies to colleagues at national and international professional meetings and receive valuable feedback about our work. In accordance with the scientific process, we’ve gone on to publish many of these studies in peer-reviewed scientific journals, an endeavor that allows for further development and dissemination of scientific ideas. You won’t find these journals, such as Behavioral Neuroscience or Hormones and Behavior, in the checkout line at your local supermarket, but they are filled with all the latest information about maintaining healthy brains.
