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Blog Post 9- Venniro et al (2018) & de Guglielmo et al (2019)




Already from reading the title of the Venniro et al (2018) paper, I became interested in finding out how the researchers were able to exceed the effect of social interactions over drug choice in rats that were already previously exposed to drug addiction. Throughout the paper I wondered how the two different factors addiction and social interaction could be so closely compared to each other in terms of reward- as their effects are relatively dissimilar in strength. From my understanding, being addicted to drugs and simply abstaining from the drug is more complex than what appears to be presented in the paper, specifically for affected humans. The aim of most animal research is to explain behavioral findings towards a clinical application as well. Therefore, if these findings were to be applied to human drug addiction, then going out to a social event or improving one’s social stimuli should improve their drug addictive behaviors. This is not what has been seen in human drug addicts, as some affected individuals even appear to relapse again after exposure to social pressure. Therefore, the researchers do not enable a correctly established clinical application of the findings throughout their study. They did include a section in the discussion about how the presented results of rats would differ to that of humans. I would be interested in reading more about how exactly these applications could be improved through future experiments. 


The second paper by de Guglielmo et al (2019) was an extension of the topic of addiction but with a large emphasis on optogenetics. Since we discussed optogenetics a lot in the beginning of the course, it was interesting to see it again in a new context. Drug addiction has different components to it, meaning it can exist as both impulsive and compulsive states. In this paper, the researchers only appear to test the effect of CRF activity during the compulsive state of abuse, which clearly is the more severe state of the two. However, the researchers could have also compared and contrasted these findings with impulsive states as well to see how data may differ. As mentioned in my blog post last week, I was curious to learn more about tolerance and withdrawal. These findings allowed for a better understanding of the particular aspects of research. Thus, the researchers succeeded in explaining that the CRF pathway involving the Central Amygdala (CeA) and bed nucleus of the stria terminalis (BNST) were essential in alcohol withdrawal in rats. However, the CRF is an essential component in the HPA-axis and thereby stress response. de Guglielmo et al did not mention this specifically, so I would appreciate more information on the effect that stress itself may have on drug addiction in future research.

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