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Blog 8: Venniro et al. (2018) & de Guglielmo et al. (2019)

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Venniro et al. (2018) & de Guglielmo et al. (2019) take two complementary approaches to furthering the study and discussion of drug addiction and dependence in rodent models and potential clinical translations. Overall, I found Venniro et al. particularly intriguing for their discussion of clinical applications but also appreciated the extensive consideration of controls used to verify de Guglielmo et al.’s methodology. 

One critique I had for de Guglielmo et al. actually relates to their use of controls and how they originally induced alcohol dependence. The alcohol-dependent rats were exposed to cycling chronic intermittent alcohol vapors in operant chambers. For both dependent and non-dependent animals, they describe unaffected levels of water and saccharin intake in control and and NpHR-expressing rats. However, I think it would have been relevant for the researchers to also expose all groups to saccharin vapor and water vapor. If they are attempting to rule out the attribution of any nonspecific behavioral effects on alcohol drinking, it is certainly possible that the saccharin vapor (water vapor should likely have no effect) affects preference for saccharin and alters their intake relative to the intake of alcohol. 

As I mentioned, Venniro et al. discussed how their social-choice model could inform addiction treatments in humans. I agree with and really appreciate the concept of humans using a global frame of reference and ‘choice bundling’ when choosing a drug over a social interaction. As an aside, I have a close family member who is a recovering gambling addict, and while gambling has its own neural considerations compared to typical drug addiction, he has often expressed how thoughts of his actions negatively impacting family and friends has kept him from relapsing. As the authors say here, their thinking goes beyond the momentary presence or absence but focuses instead on longer-term effects and outcomes. 

Given this context, I am increasingly skeptical of rodent social addiction models for their translational relevance. If we will always have to give the caveat that ‘humans think about this differently’ then, frankly, is there any relevance at all? Sure, studies focused on pharmacological-based interventions are still likely to be translatable. Yet, despite my skepticism, I can acknowledge that social models like this one are very important given what we do know about the social aspects of addiction. I don't have a solid answer as to how, but neuroscience research must continue to develop these models and create relevant ways to bridge the gap between rodent and human translation in order for their conclusions to be the most effective and beneficial. 

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