Animal models of behavior in drug addiction research:

            Addiction, or as it is called in the Diagnostic and Statistical Manual of Mental Disorders (DSMV) “Substance Use Disorder” has been a subject of interest since the beginning of the 19^th century. This behavior, defined by the American Society of Addiction Medicine as “a primary, chronic disease of brain reward, motivation, memory and related circuitry” has been studied from its neurobiological aspects, as well as its psychological aspects. Since the field of addiction spans throughout many disciplines and involves various aspects in its study, the focus of this article will be the animal models of behavior in addiction research. These models, along with their contemporary focus on addiction and which behaviors have proven to be more useful in research will be of particular interest in this piece.

            Many different types of animals have been used in addiction research throughout the years and have been crucial in the process of understanding and treating diseases and disorders. Animal models may be used to screen for the effects of a drug as well as to simulate the symptoms of a disease or disorder. 

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While other mammals are more commonly employed, most contemporary models involve mice or rats. Other contemporary models make use of invertebrates such as honeybees and fruit flies. However, models such as the traditional self-administration paradigm have been used in a variety of nonhuman primates, as well as other mammals including dogs and cats. This is largely due to the accessibility, ease of incorporation and manipulation of these organisms in research. Still, it is known that use of mice and rats is not limited to addiction research. The most important factors for the use of these organisms are the similarities in brain structure organization with that of the human brain and in genetic sequence. 

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Here are a variety of examples of different animals' brains in comparison to the human brain.

This resemblance extends to more than just the brain structures since; they also share the same neurotransmitters, receptors, proteins for synaptic vesicle release and recycling, as well as having a resemblance in signaling mechanisms.

For further information see: Berridge, K. C., Robinson, T. E., & Alridge, J. W. (2009). Dissecting components of reward: ‘liking’, ‘wanting’, and learning. Current opinions in pharmacology. 9, 65-73; Heidbreder, C. (2011). Advances in animal models of drug addiction. Current Topics in Behavioral Neuroscience, 7, 213-250; Lenoir, M., Serre, F., Cantin, L., & Ahmed, S. H. (2007). Intense sweetness surpasses cocaine reward. PLoS ONE, 2(8); Lynch, W. J., Nicholson, K. L., Dance, M. E., Morgan, R. W., & Foley, P. L. (2010). Animal models of substance abuse and addiction: Implications for science, animal welfare and society. Comparative Medicine, 60(3), 177-188; Maldonado-Vlaar, C. S. (2015). Animal Models [Powerpoint Presentation]; Meyer, J. S. & Quenzer, L.F. (2013). Psychopharmacology: Drugs, the brain and behavior (2^nd ed.). Sunderland, MA: Sinauer Associates; Self, D. W. (2015). Modification of reward, relapse and mood pathways in cocaine addiction [Powerpoint Presentation]; Vukmir, R. B. (2004). Drug seeking behavior. The American journal of drug and alcohol abuse. 30(3), 551-575; Weiss, F. (2010). Advances in the neuroscience of addiction: Advances in animal models of relapse for addiction research. Boca Raton, FL: CRC Press; Wise, R. A. & Koob, G. F. (2014). The development and maintenance of drug addiction. Neuropsychopharmacology, 39, 254-262; American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders: DSM-5. Washington, D.C: American Psychiatric Association.