Since the early 1970s, NIDA supported neuroscience research has revolutionized our understanding of drug abuse and addiction. NIDA researchers first conceptualized, then showed how opiates exploit the brain's natural reward system by mimicking naturally occurring brain chemicals and binding to the brain receptors for those chemicals to produce their addictive effects. Over the next two decades, additional discoveries about where and how drugs act in the brain repudiated the once popular and still too prevalent belief that drug addiction stems simply from a character deficiency or a lack of willpower. These discoveries by drug abuse neuroscience researchers have also revolutionized our broader view of how the brain functions.
We now know that addiction is a chronic, relapsing brain disease that humans manifest in a variety of behaviors and in a range of social circumstances, all of which are important to a full understanding of the phenomenon. NIDA's research focuses on all aspects of the brain: how the brain operates normally, how drugs affect the brain, and how drugs change the brain over the course of addiction. Therefore, NIDA is expanding its neuroscience research to ensure that neuroscience knowledge informs our entire research portfolio.
NIDA will continue to support the broad program of basic research on the neurobiology of addiction that has produced notable discoveries about the nature of drug abuse and the mechanisms of brain function. Basic research by NIDA's intramural and extramural researchers has enabled us to identify the cellular sites where nicotine, cocaine, opiates, and marijuana bind in the brain; to uncover the molecular blueprint for these sites; and to clone brain receptors for virtually every major drug of abuse. These discoveries have provided us with biochemical templates for screening potential treatment medications and for developing new compounds designed to block or attenuate the effects of cocaine and other abused drugs.
At NIDA's first National Conference on Marijuana Use, held last July, basic researchers provided another example of how neuroscience is providing the basis on which to replace ideology with facts about how drugs affect the brain. At the conference, NIDA-supported researchers reported on research with a recently developed antagonist for marijuana, which blocks the effects of the drug. Using this agent, researchers have demonstrated for the first time that marijuana may cause drug dependence in animals (see "Marijuana Antagonist Reveals Evidence of THC Dependence in Rats"). Future studies with the antagonist could potentially lead to the development of treatments for marijuana dependence.
In addition to our basic neuroscience research, we are also seizing the opportunity offered by new clinical research tools to do more research on the human brain in clinical settings. We have established an Etiology and Clinical Neurobiology Branch in the Division of Clinical and Services Research, which is being headed by Acting Branch Chief Dr. Joseph Frascella. The branch will support research that complements the work of our two basic neurobiology research branches and that of the Neuroscience and Molecular Neurobiology Branches in our Intramural Research Program (see "ARC's 60th Anniversary").
I believe human neuroscience research offers great potential for further discoveries about the brain and addictive behaviors that we can apply to improving the effectiveness of drug abuse prevention and treatment. For example, brain imaging technologies, such as positron emission tomography and functional magnetic resonance imaging, enable us to look directly into the living human brain while people are experiencing various aspects of addiction such as drug use, withdrawal, abstinence, and craving. Using these imaging techniques, researchers can see where specific drugs act in the brain, what structures are most affected, and how these drugs alter brain activity when tasks such as those involving memory and learning are performed. Unlike researchers conducting animal studies, these scientists will be able not only to look at the neurobiology underlying addiction-related phenomena but also to interview patients at the same time. This approach will enable researchers to correlate the patients' biological changes with their psychological processes.
Our new clinical neuroscience program will also support biological and neurobiological assessments that attempt to determine which underlying factors make an individual more or less likely to become dependent on drugs. The new branch also will encourage studies that examine the response of the brain while patients are undergoing different types of pharmacological and behavioral treatments. This potentially fertile research area could conceivably correlate neurobiological markers with clinical outcomes and use these markers to measure and compare the effectiveness of various therapies during different stages of treatment.
We launched our new clinical neuroscience program in 1995 with a request for applications (RFA) to conduct research on the human basic and clinical neuroscience of drug addiction. In September, we converted the RFA to a program announcement on the clinical neuroscience of drug addiction. To further expand the neuroscience research we support, we also issued an RFA to establish neuroscience networks in basic drug abuse research and a program announcement fostering neuroscience research on nicotine and nicotine abuse. In addition, we issued a program announcement soliciting research on AIDS, drug abuse, and neurobiology to increase our understanding of how drugs of abuse may compromise the central nervous system and affect the development of HIV-related dementia.
To coordinate NIDA's neuroscience research, I have established a NIDA neuroscience consortium that includes representatives from every NIDA division and office. This consortium, which is being led by Dr. Karen Skinner, deputy director of our Division of Basic Research, is disseminating information about neuroscience research throughout the Institute and reaching out to the larger scientific community. The outreach effort aims to inform the general neuroscience community about NIDA's neuroscience research, to communicate our interest in expanding our neuroscience research into new areas that may be applicable to drug abuse, and to attract neuroscience researchers from other fields to drug abuse research.
To achieve these goals, the consortium is orchestrating a number of endeavors that include:
- A home page. The neuroscience consortium has posted a home page on the Internet that is available through the World Wide Web. The home page highlights NIDA's neuroscience activities and provides users with access to current neuroscience RFA's and program announcements.
- The Human Brain Project. NIDA is one of the lead agencies in this broad-based Federal initiative to foster the development of computer-based information and communications resources that will support basic and clinical neuroscience research. A number of NIDA divisions participate with other Federal agencies in supporting joint studies both of animals and of humans.
- A conference on the expanding role of neurobiology in addiction medicine. This conference was sponsored by the American Society of Addiction Medicine in cooperation with NIDA and the National Institute on Alcohol Abuse and Alcoholism. The meeting, held in October, featured presentations by a number of NIDA's leading intramural and extramural neuroscience researchers.
- Annual meetings of the Society for Neuroscience. At the 1994 meeting, Dr. Paul Greengard of Rockefeller University kicked off a NIDA poster session with an address that commemorated more than 20 years of NIDA neuroscience research.
- A satellite symposium on nicotine research. At this NIDA-sponsored symposium, extramural researchers and scientists from NIDA's Division of Intramural Research presented the entire spectrum of NIDA's nicotine research from the molecular biology of nicotinic receptors through behavioral and pharmacological treatment of nicotine addiction. The symposium was held in conjunction with the most recent annual meeting of the Society forNeuroscience in November.
I believe the efforts NIDA is now taking to broaden and promote the role of neuroscience in drug abuse research will ultimately lead to a better understanding of addiction and foster the development of more effective medications and behavioral therapies to prevent and treat this complex brain disease.