Even though multiple brain regions might be involved in the pathogenesis of AUD, major sites are considered to be the frontal cortex, nucleus accumbens, and amygdala6. The frontal cortex is responsible for learning, decision-making, attention, and memory. Nucleus accumbens plays a critical role in processing rewarding stimuli, thus reinforcing pleasurable activities. Amygdala is a part of the limbic system which projects to nucleus accumbens and is mainly involved in the formation of emotional responses7. Alcohol crosses the brain and is capable of causing changes in gene expression in these regions, thus mediating the development of neurotoxicity, dependence, and tolerance. For example, 163 genes were altered in the superior frontal cortex in patients with AUD8. In the nucleus accumbens of rats given unlimited access to alcohol, 374 genes were altered, notably including many oncogenes9.
