Virginia Commonwealth University School of Medicine
The Dean’s Biomedical Research Seminar
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Nora Volkow, M.D.
Director, National Institute on Drug Abuse
National Institutes of Health
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Addiction: Conflict between Brain Circuits
Role of Genes, Development and the Social Environment
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Abstract: Studies employing neuroimaging technology paired with behavioral measurements, and more recently genetics, have led to remarkable progress in elucidating neurochemical and functional changes that occur in the brains of addicted subjects. Although large and rapid increases in dopamine have been linked with the rewarding properties of drugs, the addicted state, in striking contrast, is marked by significant decreases in brain dopamine D2 receptor mediated signaling. Such decreases are associated with dysfunction of prefrontal regions including orbitofrontal cortex, cingulate gyrus and dorsolateral prefrontal cortex and impaired striato frontal connectivity. In addiction, disturbances in salience attribution result in enhanced value given to drugs and drug-related stimuli at the expense of other reinforcers and promote inflexible behaviors. Dysfunction in inhibitory control systems, by decreasing the addict’s ability to refrain from seeking and consuming drugs, ultimately results in the compulsive drug intake that characterizes the disease. Discovery of such disruptions in the fine balance that normally exists between brain circuits underling reward, motivation, memory and self-control have important implications for designing multi-pronged interventions for the prevention and treatment of addictive disorders.
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Wednesday, July 17, 2013 at 3:30 P.M.
Kontos Medical Science Building Auditorium
Light Reception Following Lecture in MSB 104/105
Sponsored by: The Office of the Dean of VCU School of Medicine,
and The Department of Pharmacology and Toxicology