Studies with these selected lines have contributed a great deal to understanding the neurobiological bases for alcohol’s myriad effects. For example, researchers consistently have observed low levels of the neurotransmitter serotonin in certain brain areas (i.e., the limbic system) and other indications of dysregulation of the serotonin system in animal lines bred for high alcohol drinking (Crabbe 2008). Other studies with selected lines have shown dysregulation of the GABA and glutamate systems in animals bred to exhibit severe withdrawal. (Finn et al. 2004).
