Transcription and Reward Systems

Drug addiction is characterized by very stable behavioral abnormalities, which in turn are mediated by stable abnormalities in the brain's reward pathways. This has led to the view that drugs of abuse cause addiction, in part, by inducing long-lasting changes in gene expression in these vulnerable regions of the brain. Stable abnormalities in reward are also seen in several other psychiatric conditions (e.g., depression and mania), which implicates altered gene expression in brain reward regions in these conditions as well. The objective of this article is to summarize evidence for a role of changes in gene expression in animal models of addiction and depression and to focus on some of the particular transcription factors that underlie these maladaptive changes in brain function.